Ophthalmology – Retinal/Choroidal Coloboma

What This Condition Represents

Retinal/choroidal coloboma (chorioretinal coloboma) is a congenital ocular malformation caused by incomplete closure of the embryonic optic fissure during early gestation.

The defect may involve:

• Retina
• Retinal pigment epithelium (RPE)
• Choroid
• Optic disc
• Ciliary body
• Iris

Its effect on vision depends primarily on:

• Size of the defect
• Foveal involvement
• Optic nerve involvement
• Associated microphthalmia
• Development of retinal detachment
• Amblyopia

Even a large coloboma can coexist with relatively good central vision if the:

Macula and optic nerve are spared.

How the Defect Develops

During approximately the:

5th–7th weeks of gestation

the inferior embryonic optic fissure normally closes.

Failure of complete closure produces a colobomatous defect.

Because the embryonic fissure lies:

Inferonasally

a typical chorioretinal coloboma is found in the inferonasal fundus.

Structures That May Be Involved

Ocular coloboma may affect one or several structures, including:

• Iris
• Ciliary body
• Lens zonules
• Retina
• Choroid
• Optic nerve

A patient with a visible iris coloboma may therefore also have an occult posterior-segment coloboma.

A complete dilated examination is important.

How Common It Is

Ocular coloboma is uncommon.

Overall prevalence is approximately:

1 in 10,000 births

although estimates vary among populations and include different types of ocular coloboma.

It may be:

• Unilateral
• Bilateral
• Isolated
• Syndromic

Genetic Background

Coloboma is genetically heterogeneous.

It may occur:

• Sporadically
• With autosomal dominant inheritance
• With autosomal recessive inheritance
• With X-linked inheritance
• As part of a chromosomal or multisystem disorder

There is therefore:

No single inheritance pattern for all ocular colobomas.

Important Gene Associations

Genes associated with ocular coloboma include:

• CHD7
• PAX2
• PAX6
• SOX2
• OTX2
• RAX
• MAB21L2

among others.

Genetic evaluation becomes particularly important when there is:

• Bilateral disease
• Positive family history
• Developmental delay
• Hearing loss
• Renal disease
• Cardiac abnormality
• Other congenital malformations

CHARGE Syndrome Link

One of the most important syndromic associations is:

CHARGE syndrome

usually related to pathogenic variants in:

CHD7

The acronym refers to:

• Coloboma
• Heart defects
• Atresia of the choanae
• Retardation of growth/development
• Genital abnormalities
• Ear abnormalities

Coloboma is very common in affected children.

PAX2-Related Disease

Pathogenic variants in PAX2 can produce:

PAX2-related disorder, historically called renal-coloboma or papillorenal syndrome.

Associated findings include:

• Optic nerve dysplasia or coloboma
• Renal abnormalities
• Vesicoureteric abnormalities
• Hearing impairment in some patients

The ocular defect is frequently centered on the:

Optic nerve

rather than being a simple peripheral chorioretinal coloboma.

Other Syndromic Settings

Coloboma may also occur with:

• Aicardi syndrome
• Cat-eye syndrome
• Joubert-spectrum disorders
• Craniofacial developmental syndromes
• Chromosomal abnormalities

Systemic evaluation should therefore be guided by the overall phenotype.

What the Fundus Defect Contains

Within a chorioretinal coloboma there is deficiency or absence of:

• Normal RPE
• Choroid
• Normal retinal architecture

The underlying:

White sclera

is often directly visible.

The Intercalary Membrane

A thin dysplastic tissue may bridge the colobomatous excavation.

This is called the:

Intercalary membrane

It is clinically important because it may:

• Contain abnormal retinal tissue
• Develop holes
• Develop schisis-like changes
• Permit passage of subretinal fluid

and contribute to:

Retinal detachment.

Changes at the Coloboma Edge

The border between normal and abnormal retina may show:

• Pigmentary hyperplasia
• RPE irregularity
• Retinal thinning
• Vitreoretinal adhesion
• Small retinal breaks

These junctional abnormalities are important when assessing detachment risk.

Typical Funduscopic Appearance

The classic lesion is:

• Inferonasal
• Pale or white
• Sharply demarcated
• Excavated
• Often extending anteriorly

Severity ranges from:

• Tiny optic-disc-associated defect

to:

• Large coloboma extending from the posterior pole toward the anterior segment

Bridge-Type Configuration

Occasionally two colobomatous areas are separated by a strip of relatively normal retina.

This configuration is sometimes described as:

Bridge coloboma.

Effect on Central Vision

Visual acuity depends most strongly on whether the defect involves:

• Fovea
• Optic nerve
• Papillomacular bundle

If these are spared:

Good central acuity may be maintained despite a large coloboma.

Expected Visual Field Defect

Because the lesion is typically inferior, patients may have a corresponding:

Superior visual field defect

although field loss depends on lesion size and location.

What to Ask the Patient

Important history includes:

• Lifelong reduced vision
• New change in vision
• New peripheral field loss
• Flashes
• Floaters
• Family history of coloboma
• Hearing impairment
• Renal abnormalities
• Cardiac defects
• Growth or developmental problems
• Genitourinary abnormalities

A new field defect or sudden visual decline should raise concern for:

Retinal detachment.

What to Look for in Children

Children should be assessed for:

• Visual acuity
• Cycloplegic refractive error
• Amblyopia
• Strabismus
• Nystagmus
• Microphthalmia
• Iris coloboma
• Other congenital abnormalities

Associated developmental or systemic problems may be more clinically important than the ocular lesion itself.

Additional Ocular Findings

Chorioretinal coloboma may coexist with:

• Iris coloboma
• Optic nerve coloboma
• Microphthalmia
• Microcornea
• Cataract
• Lens abnormalities
• Strabismus
• Nystagmus

Microphthalmia With Orbital Cyst

A severe defect of optic fissure closure can be associated with:

Microphthalmia with cyst

The cyst may communicate with the globe through the embryonic fissure.

Imaging can show:

• Small malformed globe
• Inferior orbital cyst
• Communication with the eye

How the Diagnosis Is Made

Diagnosis is primarily:

Clinical

through complete dilated fundus examination.

Routine laboratory studies are unnecessary for an isolated typical lesion.

Documenting the Lesion

Useful baseline documentation includes:

• Color fundus photography
• Wide-field imaging when available

This can help monitor:

• Coloboma margins
• Retinal breaks
• Subretinal fluid
• Retinal detachment

Role of OCT

Optical coherence tomography is particularly useful for examining:

• The coloboma edge
• Intercalary membrane
• Foveal architecture
• Subretinal fluid
• Schisis-like changes

OCT may clearly show the transition from:

Normal retina → abnormal intercalary membrane

When Ultrasound Helps

B-scan ultrasonography is useful when:

• Media opacity limits examination
• Retinal detachment is suspected
• Microphthalmia with cyst is present

It is not routinely required when the lesion is clearly visible.

When Neuroimaging Is Appropriate

MRI of the brain/orbits may be considered when there is concern for:

• Optic nerve abnormality
• Microphthalmia with cyst
• Midline developmental defects
• CHARGE syndrome
• Other congenital neurologic abnormalities

MRI is generally preferred to CT in children when it can provide the needed information without ionizing radiation.

Broader Systemic Assessment

Depending on the phenotype, evaluate for:

• Hearing loss
• Cardiac defects
• Choanal atresia
• Renal disease
• Genitourinary abnormalities
• Growth delay
• Developmental delay
• Neurologic abnormalities

Genetics, pediatrics, nephrology, cardiology, or ENT referral may be appropriate depending on associated findings.

Conditions That Can Mimic It

Important alternatives include:

• Chorioretinal scar
• Toxoplasmosis scar
• Posterior staphyloma
• Traumatic chorioretinal defect
• Congenital optic nerve anomalies
• Aicardi-related chorioretinal lacunae
• North Carolina macular dystrophy

Distinguishing It From an Acquired Scar

A congenital coloboma is usually:

• Inferonasal
• Smoothly demarcated
• Present from birth
• Associated with other developmental ocular abnormalities

An acquired chorioretinal scar is more likely to be:

• Irregular
• Pigmented
• Related to inflammation, infection, trauma, or laser

Main Vision-Threatening Problem

The most important long-term complication is:

Rhegmatogenous retinal detachment

The risk is substantially higher than in the general population.

Detachment may arise from:

• Breaks within the intercalary membrane
• Breaks at the coloboma edge
• Breaks elsewhere in apparently normal retina

Why Detachment Develops

Mechanisms include:

• Weak intercalary membrane
• Vitreoretinal traction
• Retinal breaks at the margin
• Communication between fluid spaces inside and outside the coloboma

This abnormal anatomy can make repair more difficult than a routine retinal detachment.

Symptoms That Need Urgent Review

Patients should seek immediate assessment for:

• New flashes
• Sudden increase in floaters
• Curtain or shadow
• New peripheral field loss
• Sudden reduction in vision

These may indicate:

Retinal tear or detachment.

Role of Preventive Laser

Prophylactic laser around the coloboma margin has been proposed to reduce retinal detachment risk.

However:

Routine laser for every coloboma is not universally recommended.

Treatment may be considered when:

• High-risk breaks are present
• The anatomy permits a safe barrier
• A retina specialist judges detachment risk to be substantial

Laser may be difficult or unsafe near:

• Optic disc
• Fovea

Repairing a Retinal Detachment

Coloboma-associated RRD usually requires:

Pars plana vitrectomy

often combined with:

• Identification of retinal breaks
• Endolaser
• Fluid-air exchange
• Gas tamponade
• Silicone oil tamponade

Management is individualized according to anatomy.

Why Surgery Can Be Difficult

Repair is challenging because:

• Retinal breaks can lie inside the coloboma
• The intercalary membrane is fragile
• Anatomy is abnormal
• Laser uptake may be poor over bare sclera
• Optic nerve involvement may complicate treatment

When Silicone Oil Is Useful

Silicone oil is often helpful in complex cases because it provides:

Longer-lasting internal tamponade

particularly when:

• Breaks are multiple or difficult to identify
• The coloboma is extensive
• PVR risk is high

Choroidal Neovascularization

A less common complication is:

Choroidal neovascularization (CNV)

usually arising near the edge of the coloboma.

Symptoms may include:

• New central blur
• Metamorphopsia
• Macular hemorrhage

Managing Coloboma-Associated CNV

Treatment is generally:

Intravitreal anti-VEGF therapy

with OCT ± OCTA/FA used to monitor activity.

Correcting Optical Problems

Treat significant:

• Myopia
• Hyperopia
• Astigmatism
• Anisometropia

especially during childhood.

Cycloplegic refraction is important in children at risk of:

Amblyopia.

Protecting Visual Development

Amblyopia management may include:

• Full refractive correction
• Patching
• Atropine penalization in selected cases

Potential for improvement depends on whether reduced vision is caused by:

• Amblyopia

rather than irreversible structural damage involving the fovea or optic nerve.

Vision Rehabilitation

Patients with irreversible impairment may benefit from:

• Low-vision assessment
• Magnification
• Electronic aids
• Educational accommodations
• Orientation and mobility training

Long-Term Surveillance

Follow-up frequency should be individualized according to:

• Size of defect
• Macular involvement
• Fellow-eye findings
• Prior retinal detachment
• Age
• Symptoms
• Associated syndrome

Periodic dilated retinal examination is important because retinal detachment can occur later in life.

Expected Visual Outcome

Visual prognosis varies widely.

Important determinants include:

• Foveal involvement
• Optic nerve involvement
• Microphthalmia
• Retinal detachment
• Amblyopia

The absolute size of the coloboma is less important than:

Which critical visual structures are involved.

Reproductive and Family Considerations

Because some forms are inherited, genetic counseling may be useful for affected individuals planning pregnancy, especially when there is:

• Known genetic diagnosis
• Bilateral coloboma
• Positive family history
• Associated congenital syndrome

Recurrence risk depends on the:

Specific genetic cause, not merely the presence of coloboma.

Possible Long-Term Sequelae

Complications include:

• Rhegmatogenous retinal detachment
• Refractive error
• Amblyopia
• Strabismus
• Nystagmus
• Choroidal neovascularization
• Permanent visual field loss
• Reduced visual acuity

Ophthalmology Pearls

• Chorioretinal coloboma results from incomplete closure of the embryonic optic fissure and therefore classically lies inferonasally.
• It may involve the iris, ciliary body, choroid, retina, and optic nerve in varying combinations.
• The defect lacks normal RPE and choroid, making the white sclera visible.
• The thin abnormal retinal tissue spanning the coloboma is the intercalary membrane.
• Visual acuity depends mainly on foveal and optic nerve involvement, not simply on lesion size.
• A large coloboma may coexist with good central vision if the macula and disc are spared.
• The most important late ocular complication is rhegmatogenous retinal detachment.
• Retinal breaks may occur within the intercalary membrane, at the coloboma margin, or elsewhere in the retina.
• Coloboma-associated retinal detachment is often complex and commonly requires vitrectomy with endolaser and gas or silicone oil tamponade.
• Routine prophylactic laser around every coloboma is not universally recommended.
• OCT is particularly useful for showing the coloboma margin, intercalary membrane, and subretinal fluid.
• Choroidal neovascularization may arise at the lesion edge and is usually treated with anti-VEGF therapy.
• Children require assessment for refractive error, amblyopia, strabismus, microphthalmia, and syndromic disease.
• Important genetic associations include CHD7 in CHARGE syndrome and PAX2-related renal/optic nerve disease.
• Bilateral coloboma or associated developmental abnormalities should increase consideration for genetic and systemic evaluation.
• New flashes, floaters, curtain-like field loss, or sudden visual deterioration should be treated as possible retinal detachment until excluded.

Ophthalmology – Retinal Microaneurysms

Basics

Description

Retinal microaneurysms (MAs) are tiny focal saccular or fusiform dilatations of retinal capillaries.

Clinically they appear as:

• Small red dots
• Usually in the posterior pole
• Often concentrated around the macula

They are an important marker of:

Retinal microvascular disease

and are classically associated with:

• Diabetic retinopathy
• Retinal vein occlusion
• Hypertensive microvascular disease
• Radiation retinopathy

Microaneurysms may:

• Remain stable
• Thrombose
• Disappear
• Leak plasma
• Rupture into a dot hemorrhage

Key Clinical Concept

A retinal microaneurysm is:

A vascular lesion, not simply a small hemorrhage

The distinction is easiest with angiography:

• Microaneurysm → typically hyperfluorescent
• Dot hemorrhage → typically blocks fluorescence

Anatomy

Microaneurysms arise from retinal capillaries, particularly within the:

• Inner nuclear layer
• Deep capillary plexus
• Occasionally more superficial capillary networks

They are often located near:

• Areas of capillary nonperfusion
• Venous abnormalities
• Regions of chronic vascular stress

Epidemiology

The prevalence of retinal microaneurysms depends strongly on the underlying disease.

They are common in:

• Diabetes mellitus
• Hypertension
• Retinal vein occlusion

They may occasionally occur in otherwise healthy older adults, particularly in association with:

• Hypertension
• Other systemic vascular risk factors

Diabetes

Microaneurysms are one of the earliest clinically detectable lesions of:

Diabetic retinopathy

In standard diabetic retinopathy classification:

Microaneurysms only = mild nonproliferative diabetic retinopathy

provided no more advanced lesion is present.

Risk Factors

Major systemic and ocular risk factors include:

• Diabetes mellitus
• Hypertension
• Dyslipidemia
• Chronic kidney disease
• Retinal vein occlusion
• Retinal ischemia
• Radiation exposure to the retina
• Hyperviscosity states

Pathophysiology

Microaneurysms develop because of:

• Pericyte loss
• Endothelial dysfunction
• Capillary basement membrane abnormalities
• Loss of capillary wall support
• Local retinal ischemia
• Chronic inflammatory signaling

This causes focal weakening of the capillary wall and:

Aneurysmal outpouching

Pericytes

Pericytes normally help maintain:

• Capillary wall integrity
• Blood-retinal barrier function
• Microvascular autoregulation

Their loss, particularly in diabetic retinopathy, promotes:

• Microaneurysm formation
• Leakage
• Capillary instability

Blood-Retinal Barrier Breakdown

Microaneurysms may become incompetent and leak:

• Fluid
• Lipoprotein
• Plasma proteins

This contributes to:

• Retinal edema
• Hard exudates
• Diabetic macular edema

Microaneurysm Rupture

A microaneurysm can rupture and produce:

Dot or blot retinal hemorrhage

Thus microaneurysms and dot hemorrhages may coexist and can be difficult to distinguish ophthalmoscopically.

Microaneurysm Turnover

Microaneurysms are dynamic lesions.

Over time:

• New microaneurysms may appear
• Existing ones may disappear through thrombosis or remodeling

A high rate of microaneurysm formation and disappearance may reflect:

Active retinal microvascular disease

particularly in diabetes.

Clinical Presentation

Microaneurysms themselves are usually:

Asymptomatic

Visual symptoms occur when the underlying vascular disease causes:

• Macular edema
• Retinal ischemia
• Hemorrhage
• Exudation
• Neovascular complications

Visual Symptoms

Patients may experience:

• Blurred central vision
• Metamorphopsia
• Reduced contrast
• Reduced reading vision

when associated with:

Macular edema

Funduscopic Appearance

Microaneurysms appear as:

• Tiny
• Round
• Red
• Sharply defined dots

They are usually:

Smaller than most dot-blot hemorrhages

but size overlap makes clinical distinction imperfect.

Distribution in Diabetic Retinopathy

In diabetes, microaneurysms commonly occur:

• In the posterior pole
• Temporal to the fovea
• Near areas of capillary closure

They may be accompanied by:

• Dot-blot hemorrhages
• Hard exudates
• Cotton-wool spots
• Venous beading
• IRMA
• Macular edema

Distribution in Retinal Vein Occlusion

In retinal vein occlusion, microaneurysms may appear:

• Within the involved venous drainage territory
• Near areas of chronic edema
• After acute hemorrhages have largely resolved

They may persist as a marker of:

Chronic post-occlusive microvascular remodeling

Peripheral Microaneurysms

Peripheral retinal microaneurysms may occur in:

• Diabetic retinopathy
• Sickle cell retinopathy
• Radiation retinopathy
• Retinal telangiectasia
• Chronic retinal vein occlusion
• Hyperviscosity states

The interpretation depends on:

• Distribution
• Associated ischemia
• Other retinal findings

Diagnosis

Diagnosis is usually made through:

• Dilated fundus examination
• Color fundus photography
• OCT when macular edema is suspected
• Fluorescein angiography when vascular detail is needed

Color Fundus Photography

Microaneurysms appear as:

Tiny red dots

Photography is useful for:

• Documentation
• Screening
• Serial comparison
• Diabetic retinopathy grading

Automated image-analysis systems may also detect microaneurysms in diabetic screening programs.

Red-Free Imaging

Red-free photography enhances contrast of:

• Retinal vessels
• Microaneurysms
• Hemorrhages
• Nerve fiber layer lesions

It is supportive but not essential.

Fluorescein Angiography

FA is particularly useful when distinction from hemorrhage is uncertain.

A microaneurysm typically appears as:

A punctate hyperfluorescent lesion in the early or mid angiographic phases

and may show:

• Late leakage

if incompetent.

Microaneurysm vs Dot Hemorrhage on FA

Microaneurysm

• Hyperfluorescent
• May leak

Dot Hemorrhage

• Hypofluorescent
• Blocks underlying fluorescence

This is one of the classic angiographic distinctions.

OCT

OCT does not primarily diagnose isolated microaneurysms but is essential when assessing:

• Macular edema
• Intraretinal cysts
• Subretinal fluid
• Hard exudates
• Retinal thickness

In modern practice, OCT often determines whether treatment is needed more directly than the number of microaneurysms.

OCT Appearance

Individual microaneurysms may appear as:

• Small round or oval hyperreflective vascular structures
• Sometimes with a hyporeflective lumen

They are often associated with:

• Adjacent intraretinal fluid
• Hyperreflective exudative material

OCT Angiography

OCTA may demonstrate:

• Capillary flow abnormalities
• Microaneurysmal outpouchings
• Capillary dropout
• Foveal avascular zone abnormalities

However:

OCTA does not show leakage

so it does not replace fluorescein angiography when leakage assessment is important.

Systemic Evaluation

When retinal microaneurysms are newly identified without a known cause, evaluate for:

• Diabetes
• Hypertension
• Dyslipidemia
• Other vascular disease

Typical assessment may include:

• Blood pressure
• HbA1c or fasting glucose
• Lipid profile when appropriate

Further testing depends on the clinical pattern.

Differential Diagnosis

Microaneurysm-like lesions may occur with:

• Diabetic retinopathy
• Branch retinal vein occlusion
• Central retinal vein occlusion
• Hypertensive retinopathy
• Radiation retinopathy
• Macular telangiectasia
• Sickle cell retinopathy
• Retinal vasculitis
• Hyperviscosity syndromes
• Coats disease and related telangiectatic disorders

Microaneurysm vs Dot Hemorrhage

Clinically:

Microaneurysm

• Smaller
• More sharply circular
• Vascular origin
• Hyperfluorescent on FA

Dot Hemorrhage

• Often slightly larger
• Represents extravasated blood
• Blocks fluorescence on FA

Fundoscopy alone may not always distinguish them.

Microaneurysm vs IRMA

Intraretinal microvascular abnormalities (IRMA) are remodeled intraretinal vascular channels associated with substantial capillary nonperfusion.

IRMA are:

• Larger
• More irregular
• Often adjacent to ischemic retina

and indicate more advanced diabetic retinopathy than isolated microaneurysms.

Microaneurysm vs Telangiectasia

Telangiectatic retinal vessels are:

• Dilated
• Irregular
• Often elongated or branching

whereas microaneurysms are:

Discrete focal capillary outpouchings

Treatment Principles

There is usually:

No indication to treat an isolated microaneurysm simply because it is present.

Treatment is directed toward:

1. The underlying systemic disease
2. Associated macular edema
3. Associated retinal ischemia or neovascular disease

Systemic Risk-Factor Control

Important measures include:

• Good glycemic control
• Blood pressure control
• Dyslipidemia treatment
• Smoking cessation
• Renal and cardiovascular risk management

These reduce progression of diabetic and hypertensive retinal microvascular disease.

Diabetic Macular Edema

When microaneurysm leakage contributes to:

Center-involving diabetic macular edema with visual impairment

the modern first-line treatment is generally:

Intravitreal anti-VEGF therapy

rather than focal laser to individual microaneurysms.

Anti-VEGF Therapy

Common agents include:

• Aflibercept
• Ranibizumab
• Bevacizumab
• Faricimab

depending on:

• Visual acuity
• OCT anatomy
• Availability
• Cost
• Response

Focal/Grid Laser

Focal/grid laser has a more limited role than historically.

It may still be considered for:

• Non-center-involving diabetic macular edema
• Persistent focal leakage away from the foveal center
• Selected chronic cases

Direct Focal Laser to Microaneurysms

Older treatment algorithms emphasized direct laser photocoagulation of leaking microaneurysms.

Today:

Direct focal treatment is not first-line for center-involving DME

because anti-VEGF therapy generally provides better visual outcomes.

When focal laser is used, treatment near the fovea must be cautious because scars can:

• Enlarge
• Produce paracentral scotoma
• Damage central vision

Retinal Vein Occlusion

If microaneurysms occur with vein-occlusion-related macular edema:

Anti-VEGF therapy is usually first-line

with corticosteroid therapy considered in selected cases.

The microaneurysms themselves are not usually directly treated.

Radiation Retinopathy

For radiation maculopathy with edema:

Anti-VEGF therapy is the principal modern treatment

often requiring repeated injections.

Hypertensive Retinopathy

Management is directed toward:

Systemic blood pressure control

There is no ocular treatment specifically for isolated hypertensive microaneurysms.

Follow-Up

Follow-up depends on the underlying disorder.

Monitor:

• Visual acuity
• Fundus appearance
• Retinopathy severity
• Macular OCT
• Systemic risk-factor control

Diabetic Retinopathy Monitoring

The presence of microaneurysms establishes at least:

Mild nonproliferative diabetic retinopathy

if diabetes is present and no other more advanced features exist.

Follow-up interval then depends on:

• Overall retinopathy stage
• DME
• Pregnancy
• Systemic control
• Fellow-eye status

Prognosis

An isolated retinal microaneurysm may:

• Persist
• Thrombose
• Disappear spontaneously

Its prognosis depends mostly on:

The underlying microvascular disease

rather than on the lesion itself.

Visual Prognosis

Microaneurysms threaten vision primarily when they cause:

• Macular edema
• Hard exudation near the fovea

or occur as part of more advanced ischemic retinopathy.

Complications

Potential consequences include:

• Dot-blot hemorrhage
• Retinal edema
• Hard exudates
• Macular edema
• Visual loss

The broader underlying disease may additionally lead to:

• Retinal ischemia
• Neovascularization
• Vitreous hemorrhage
• Tractional retinal detachment

Ophthalmology Pearls

• Retinal microaneurysms are focal dilatations of retinal capillaries and are among the earliest clinically detectable signs of diabetic retinopathy.
• In a patient with diabetes, microaneurysms only = mild NPDR.
• They arise from capillary wall weakness associated with pericyte loss, endothelial dysfunction, and blood-retinal barrier breakdown.
• Microaneurysms may leak, producing retinal edema and hard exudates, or rupture, producing dot hemorrhages.
• On ophthalmoscopy, microaneurysms and dot hemorrhages can look similar; FA helps distinguish them.
• On fluorescein angiography, a microaneurysm is usually punctate hyperfluorescent, while a hemorrhage blocks fluorescence.
• OCT is the key test when macular edema is suspected, because treatment decisions depend more on macular structure than on microaneurysm count.
• OCTA can show capillary abnormalities but cannot demonstrate leakage.
• Newly identified microaneurysms without an established diagnosis should prompt assessment for diabetes and hypertension.
• Important associated conditions include diabetic retinopathy, retinal vein occlusion, hypertensive retinopathy, radiation retinopathy, and retinal telangiectatic disease.
• Isolated microaneurysms usually require no direct ocular treatment.
• For center-involving diabetic macular edema, intravitreal anti-VEGF therapy is first-line, not focal laser to individual microaneurysms.
• Focal/grid laser now has a more selective role, particularly for non-center-involving edema or persistent focal leakage away from the foveal center.
• The significance and prognosis of retinal microaneurysms depend primarily on the underlying retinal vascular disorder and presence of macular edema or ischemia.

Ophthalmology – Retinal Arterial Macroaneurysm

Basics

Description

A retinal arterial macroaneurysm (RAM) is an acquired focal dilatation of a retinal arteriole, usually involving one of the first few orders of arterial branching.

It may be:

• Saccular
• Fusiform

and most often occurs at:

• Arteriolar bifurcations
• Arteriovenous crossings

The superotemporal retinal artery is a commonly recognized location.

RAM may remain asymptomatic or cause visual loss through:

• Retinal hemorrhage
• Vitreous hemorrhage
• Macular edema
• Lipid exudation
• Submacular hemorrhage
• Less commonly exudative retinal detachment

Key Clinical Pattern

The classic patient is:

An older hypertensive woman with sudden painless monocular visual loss and multilayer retinal hemorrhage centered on a retinal arteriole.

However, some RAMs present instead with slowly progressive vision loss from:

Chronic macular exudation and edema.

Epidemiology

RAM usually occurs in:

• Older adults
• Most commonly patients >60 years
• Women more often than men

Disease is usually:

• Unilateral
• Solitary

but:

• Multiple RAMs may occur
• Bilateral disease is possible

Risk Factors

The strongest systemic association is:

Arterial hypertension

Other associations include:

• Atherosclerotic cardiovascular disease
• Dyslipidemia
• Increasing age
• Retinal vein occlusion
• Other systemic vascular disease

Systemic Evaluation

Every newly diagnosed RAM should prompt:

• Blood pressure measurement
• Review of cardiovascular risk factors

and appropriate management of:

• Hypertension
• Dyslipidemia
• Diabetes if present
• Smoking and other vascular risks

Systemic treatment does not immediately eliminate the RAM but reduces overall vascular morbidity.

Pathophysiology

Age-related and hypertensive changes produce:

• Arteriolar wall sclerosis
• Loss of elastic tissue
• Smooth muscle degeneration
• Focal wall weakness

This predisposes a retinal arteriole to:

Focal aneurysmal dilation

Hemorrhagic RAM

A hemorrhagic RAM may rupture suddenly and produce:

• Subretinal hemorrhage
• Intraretinal hemorrhage
• Preretinal/subhyaloid hemorrhage
• Vitreous hemorrhage

Simultaneous hemorrhage at several retinal levels is highly suggestive of:

Retinal arterial macroaneurysm.

Exudative RAM

Some RAMs leak chronically without major rupture.

This produces:

• Macular edema
• Circinate hard exudates
• Intraretinal lipid
• Subretinal fluid

Vision may decline:

Gradually rather than suddenly.

Quiescent RAM

Some macroaneurysms are discovered incidentally and have:

• No hemorrhage
• No significant exudation
• No macular involvement

These often require:

Observation only.

Clinical Presentation

Patients may be:

• Asymptomatic
• Mildly blurred
• Profoundly visually impaired

The presentation depends on whether the RAM causes:

• Hemorrhage
• Exudation
• Macular involvement

Sudden Visual Loss

Acute painless visual loss typically occurs when the RAM ruptures and causes:

• Premacular hemorrhage
• Submacular hemorrhage
• Vitreous hemorrhage

Gradual Visual Loss

Subacute or chronic blurred vision usually results from:

• Macular edema
• Hard exudates
• Chronic subretinal fluid

Fundus Examination

A RAM appears as:

• Round or fusiform arterial dilatation
• Usually along a major retinal arteriole
• Often near an arterial bifurcation

It may be surrounded by:

• Hemorrhage
• Hard exudates
• Retinal edema

Pulsation

Occasionally the aneurysm may appear:

Pulsatile

on ophthalmoscopy or angiography.

This is not required for diagnosis.

Multilevel Hemorrhage

One of the most useful diagnostic clues is hemorrhage occurring simultaneously:

• Beneath the retina
• Within the retina
• In front of the retina
• Into the vitreous

This reflects rupture from an arterial source through several tissue planes.

Subretinal Hemorrhage

Subretinal hemorrhage may extend toward:

The fovea

and can cause permanent photoreceptor/RPE damage if:

• Thick
• Large
• Persistent

Premacular Hemorrhage

Preretinal or sub-ILM blood may produce:

• Sudden profound central visual loss

while leaving peripheral vision relatively preserved.

Vitreous Hemorrhage

If blood enters the vitreous cavity, patients may experience:

• Sudden floaters
• Haze
• Marked visual reduction

Dense vitreous hemorrhage can temporarily obscure the underlying RAM.

Hard Exudates

Chronic vascular leakage may produce:

• Circinate lipid exudation
• Macular hard exudates

These can remain after the macroaneurysm itself has thrombosed.

Diagnosis

Diagnosis is usually made from:

• Clinical examination
• OCT
• Fluorescein angiography when needed

ICGA can be especially helpful when hemorrhage obscures the lesion.

Optical Coherence Tomography

OCT is central to modern evaluation, particularly when the macula is involved.

It can demonstrate:

• Intraretinal fluid
• Cystoid macular edema
• Subretinal fluid
• Hyperreflective hemorrhage
• Subretinal hyperreflective material
• Structural foveal damage

Serial OCT is useful for monitoring:

Response to treatment and spontaneous resolution.

Fluorescein Angiography

FA may show:

• Early arterial filling of the RAM
• Focal hyperfluorescence
• Late leakage
• Adjacent capillary changes

A thrombosed RAM may show:

• Partial filling
• No filling

Indocyanine Green Angiography

ICG angiography is especially useful when hemorrhage obscures the aneurysm.

Its longer wavelength penetrates:

• Blood
• Pigment

better than fluorescein.

This can help distinguish RAM from:

• Polypoidal choroidal vasculopathy
• Choroidal neovascularization

OCT Angiography

OCTA may demonstrate:

• Flow within the macroaneurysm
• Reduced or absent flow after thrombosis

Its usefulness may be limited by:

• Hemorrhage
• Motion artifact
• Segmentation error

B-Scan Ultrasonography

B-scan is not routinely needed for RAM itself.

It may be useful if there is:

• Dense vitreous hemorrhage

to exclude:

• Retinal detachment
• Intraocular mass

Differential Diagnosis

Important differentials include:

• Polypoidal choroidal vasculopathy
• Neovascular AMD
• Retinal vein occlusion
• Diabetic retinopathy
• Retinal capillary hemangioblastoma
• Retinal vasoproliferative tumor
• Coats-like telangiectasia
• Retinal cavernous hemangioma
• Peripheral exudative hemorrhagic chorioretinopathy
• Choroidal neovascularization

RAM vs Polypoidal Choroidal Vasculopathy

RAM

• Lies on a retinal arteriole
• Arterial origin
• Often shows multilayer hemorrhage
• Visible on retinal vascular examination

PCV

• Choroidal vascular lesion
• Often sub-RPE
• Associated with serosanguineous PED
• Best characterized with ICG/OCT

RAM vs Retinal Vein Occlusion

Retinal vein occlusion typically shows:

• Venous dilation
• Venous tortuosity
• Sectoral or diffuse hemorrhage

RAM instead shows:

• A discrete arterial lesion
• Often focal multilayer hemorrhage

RAM vs Neovascular AMD

Neovascular AMD usually has:

• Drusen or other AMD changes
• Subretinal/intraretinal fluid
• CNV-related hemorrhage

RAM should be suspected when hemorrhage is centered on:

A retinal arteriole.

Treatment Principles

Management depends on:

• Visual acuity
• Macular involvement
• Hemorrhage location
• Degree of exudation
• Spontaneous improvement

Many RAMs undergo:

Spontaneous thrombosis and involution

so observation is appropriate in many cases.

Observation

Observation is appropriate when:

• RAM is asymptomatic
• Hemorrhage is away from the fovea
• Macular edema is mild
• Vision is improving
• Spontaneous thrombosis is occurring

Follow-up should include:

• Visual acuity
• Fundus examination
• OCT

Systemic Management

Control:

• Hypertension
• Dyslipidemia
• Other cardiovascular risk factors

This is an essential component of care.

Anti-VEGF Therapy

Intravitreal anti-VEGF has become an important treatment for symptomatic RAM with:

• Macular edema
• Subretinal fluid
• Significant exudation
• Submacular hemorrhage in selected cases

Agents may include:

• Bevacizumab
• Ranibizumab
• Aflibercept

Anti-VEGF Effects

Anti-VEGF may:

• Reduce macular edema
• Reduce subretinal fluid
• Accelerate hemorrhage absorption in some cases
• Improve visual acuity

However:

Many RAMs resolve spontaneously, so not every patient requires injection.

Laser Photocoagulation

Laser may be considered for:

• Persistent exudative RAM
• Macular-threatening leakage
• Chronic edema not resolving spontaneously

Modern practice uses laser more selectively than older treatment algorithms.

Direct Laser

Direct treatment targets:

The macroaneurysm itself

Potential problems include:

• Arterial occlusion
• Distal retinal ischemia
• Hemorrhage
• Vessel damage

Therefore direct laser is used cautiously.

Indirect Laser

Laser can instead be applied to:

• Surrounding leaking capillary bed
• Adjacent areas of exudation

without directly whitening the arterial aneurysm.

This may reduce leakage with less risk of arterial occlusion.

Laser Limitations

Laser should generally be avoided when:

• Hemorrhage blocks visualization
• Lesion lies very near the fovea
• Spontaneous improvement is already occurring

Premacular Hemorrhage

Large premacular hemorrhage may be managed by:

• Observation
• Nd:YAG hyaloidotomy/membranotomy in carefully selected cases
• Vitrectomy

Choice depends on:

• Hemorrhage location
• Duration
• Thickness
• Relationship to ILM/posterior hyaloid
• Visual needs

Nd:YAG Membranotomy

In a selected large premacular subhyaloid or sub-ILM hemorrhage, Nd:YAG laser may create an opening allowing blood to drain into:

The vitreous cavity

where it can clear more rapidly.

Risks include:

• Macular injury
• Retinal break
• Epiretinal membrane
• Persistent vitreous hemorrhage

It should only be performed in appropriately selected eyes.

Submacular Hemorrhage

Large thick subfoveal hemorrhage is particularly vision-threatening because blood can damage photoreceptors through:

• Mechanical separation
• Iron toxicity
• Fibrin contraction

Early displacement may be considered in selected cases.

Pneumatic Displacement

Treatment may include:

• Intravitreal expansile gas
• Often combined with intravitreal or subretinal tPA
• Frequently combined with anti-VEGF

The goal is to:

Displace blood away from the fovea.

Tissue Plasminogen Activator

tPA helps liquefy clot so that gas can displace it.

Routes include:

• Intravitreal
• Subretinal during vitrectomy

Technique depends on:

• Hemorrhage size
• Thickness
• Duration
• Surgeon preference

Vitrectomy

Pars plana vitrectomy may be considered for:

• Nonclearing vitreous hemorrhage
• Dense premacular hemorrhage
• Large recent submacular hemorrhage
• Associated tractional complications

Subretinal tPA During Vitrectomy

For large thick recent submacular hemorrhage, surgery may include:

• PPV
• Subretinal tPA
• Gas tamponade

with the goal of:

Pneumatically displacing blood from beneath the fovea.

This is generally reserved for selected severe cases.

Retinal Detachment

Retinal detachment is uncommon but can occur secondary to:

• Extensive exudation
• Surgical complications
• Other coincident retinal disease

Treatment follows the underlying mechanism.

Follow-Up

Follow-up frequency depends on:

• Macular involvement
• Hemorrhage size
• Edema
• Treatment

Active symptomatic lesions may require review every:

Several weeks initially

with OCT.

Signs of Involution

A macroaneurysm may:

• Thrombose
• Shrink
• Become fibrotic
• Leave arterial kinking
• Leave surrounding lipid or scar

Prognosis

Overall prognosis is often:

Good

because many RAMs thrombose and involute spontaneously.

Visual outcome depends primarily on:

• Foveal hemorrhage
• Macular edema
• Duration of submacular blood
• Chronic lipid exudation
• Macular scar formation

Good Prognostic Features

Better outcomes occur when:

• Macula is spared
• Hemorrhage is limited
• Edema resolves quickly
• RAM thromboses spontaneously

Poor Prognostic Features

Poorer visual outcome is associated with:

• Large subfoveal hemorrhage
• Persistent macular edema
• Dense lipid deposition
• Foveal fibrosis
• Chronic outer retinal damage

Complications

Potential complications include:

• Macular edema
• Submacular hemorrhage
• Premacular hemorrhage
• Vitreous hemorrhage
• Lipid exudation
• Macular scar
• Epiretinal membrane
• Rare retinal detachment
• Permanent central visual loss

Ophthalmology Pearls

• Retinal arterial macroaneurysm is an acquired focal dilatation of a retinal arteriole, usually occurring in older hypertensive women.
• The superotemporal retinal artery is a common site.
• RAM may present as hemorrhagic, exudative, or quiescent disease.
• A particularly helpful clue is multilevel hemorrhage—subretinal, intraretinal, preretinal, and/or vitreous—from a lesion centered on a retinal arteriole.
• Sudden visual loss suggests rupture and hemorrhage, whereas gradual visual decline suggests macular edema or chronic exudation.
• Always check blood pressure and systemic vascular risk factors.
• OCT is the key modern test for macular edema, subretinal fluid, and structural foveal damage.
• FA identifies the arterial lesion and leakage; ICG is particularly useful when blood obscures the macroaneurysm.
• Many RAMs spontaneously thrombose and involute, so observation is appropriate when the macula is not threatened.
• Anti-VEGF therapy is commonly used for symptomatic RAM with macular edema, subretinal fluid, or selected hemorrhagic presentations.
• Laser is now used selectively for persistent exudative leakage, with caution because direct treatment can produce arterial occlusion or distal ischemia.
• Large premacular hemorrhage may occasionally be treated with Nd:YAG membranotomy or vitrectomy in selected cases.
• Large recent submacular hemorrhage may require pneumatic displacement ± tPA or vitrectomy with subretinal tPA.
• The main determinants of final vision are foveal hemorrhage, persistent macular edema, lipid deposition, and macular scarring.
• The retina may recover well after the aneurysm involutes, but prolonged subfoveal blood can cause permanent photoreceptor damage.

Ophthalmology – Retinal Hemorrhages

Basics

Description

Retinal hemorrhages (RH) are collections of blood within, beneath, or in front of the neurosensory retina.

Their appearance depends strongly on the retinal layer involved.

They may be:

• Superficial intraretinal
• Deep intraretinal
• Preretinal/subhyaloid
• Sub–internal limiting membrane (sub-ILM)
• Subretinal
• Occasionally associated with vitreous hemorrhage

Retinal hemorrhage is a:

Clinical sign rather than a diagnosis

and its significance depends on:

• Age
• Distribution
• Number
• Retinal layer
• Laterality
• Associated ocular findings
• Systemic context

Major Clinical Principle

The morphology and distribution of hemorrhage provide important diagnostic clues.

For example:

• Flame-shaped hemorrhages → superficial nerve fiber layer
• Dot-blot hemorrhages → deeper retinal layers
• Boat-shaped/preretinal hemorrhage → blood between posterior hyaloid or ILM and retina
• Subretinal hemorrhage → blood beneath neurosensory retina

Retinal Anatomy and Hemorrhage Shape

The retinal architecture determines the appearance of blood.

Superficial Retina

Blood spreads along retinal nerve fibers, producing:

Flame-shaped or splinter hemorrhages

Deep Retina

Blood is confined by vertically oriented retinal structures, producing:

Dot or blot hemorrhages

Preretinal Space

Blood may form a:

Boat-shaped or horizontally layered hemorrhage

because it settles under gravity.

Flame-Shaped Hemorrhages

Flame hemorrhages occur in the:

Retinal nerve fiber layer

Common associations include:

• Hypertensive retinopathy
• Retinal vein occlusion
• Papilledema
• Anemia
• Leukemia
• Abusive head trauma

Dot-Blot Hemorrhages

Dot-blot hemorrhages arise in deeper retinal layers.

Common associations include:

• Diabetic retinopathy
• Retinal vein occlusion
• Blood dyscrasias
• Severe retinal ischemia

Preretinal / Subhyaloid Hemorrhage

Blood accumulates between the:

• Posterior hyaloid and retina

or beneath the ILM.

It may appear:

• Round
• Dome-shaped
• Boat-shaped

Common causes include:

• Valsalva retinopathy
• Proliferative diabetic retinopathy
• Retinal neovascularization
• Trauma
• Terson syndrome

Sub-ILM Hemorrhage

Sub-ILM hemorrhage lies between:

• Internal limiting membrane
• Retinal nerve fiber layer

It can appear sharply demarcated and may mimic subhyaloid hemorrhage.

Large premacular collections can cause:

Marked central visual loss

Subretinal Hemorrhage

Subretinal blood lies beneath the:

Neurosensory retina

Common causes include:

• Neovascular age-related macular degeneration
• Myopic CNV
• Trauma
• Polypoidal choroidal vasculopathy
• Retinal macroaneurysm
• Severe choroidal vascular disease

White-Centered Retinal Hemorrhages

White-centered hemorrhages are traditionally called:

Roth spots

The white center may represent:

• Fibrin
• Platelet aggregates
• Ischemic retinal tissue
• Leukemic or inflammatory material

They are:

Nonspecific

and can occur with:

• Infective endocarditis
• Leukemia
• Severe anemia
• Sepsis
• Diabetes
• Hypertension
• Other systemic illness

They are not pathognomonic of endocarditis.

Epidemiology

The frequency of retinal hemorrhage depends entirely on the population and underlying disease.

Important contexts include:

• Newborn retinal hemorrhage
• Retinal vascular disease
• Trauma
• Hematologic disease
• Intracranial disease
• Abusive head trauma

Newborn Retinal Hemorrhage

Retinal hemorrhage is relatively common after delivery, especially following:

• Vaginal delivery
• Vacuum-assisted delivery
• Forceps delivery

It is less common after:

• Cesarean delivery

Most neonatal hemorrhages:

Resolve spontaneously over days to weeks

without visual consequence.

Pediatric Importance

In infants and young children, retinal hemorrhage may result from:

• Birth-related injury
• Accidental trauma
• Abusive head trauma
• Coagulopathy
• Leukemia
• Severe systemic illness
• Intracranial disease

The pattern must always be interpreted together with:

• History
• Neurologic findings
• Systemic evaluation
• Neuroimaging

Abusive Head Trauma

Abusive head trauma (AHT) is an important cause of retinal hemorrhage in infants and young children.

Retinal findings that are especially concerning include:

• Numerous hemorrhages
• Bilateral involvement
• Multilayer hemorrhages
• Extension from posterior pole to peripheral retina
• Retinoschisis
• Perimacular retinal folds

However:

No single retinal finding is independently diagnostic of abuse.

The diagnosis requires integration of:

• Ophthalmic findings
• History
• Neuroimaging
• Skeletal findings
• Laboratory evaluation
• Multidisciplinary child-protection assessment

Important Modern Terminology

The preferred term is:

Abusive head trauma

rather than “shaken baby syndrome,” because injury may involve:

• Acceleration-deceleration
• Rotation
• Impact
• Combinations of mechanisms

Mechanisms in AHT

Proposed mechanisms include:

• Vitreoretinal traction from repetitive acceleration-deceleration
• Increased intracranial and venous pressure
• Hypoxic-ischemic injury
• Vascular dysregulation

The exact contribution of each mechanism varies.

Retinoschisis

Traumatic retinoschisis in AHT typically involves:

• Macula
• Perimacular retina

and may contain:

• Sub-ILM blood
• Intraretinal blood

Associated perimacular folds are highly concerning in the appropriate clinical context.

CPR and Retinal Hemorrhage

Cardiopulmonary resuscitation alone generally causes:

• No retinal hemorrhage
• Or only limited posterior hemorrhage

Extensive multilayer hemorrhages extending to the periphery are:

Not typically explained by uncomplicated CPR alone.

Birth-Related Retinal Hemorrhage

Neonatal birth hemorrhages are usually:

• Intraretinal
• Posterior pole predominant
• Self-resolving

Most resolve within:

• Several days to a few weeks

Some deeper hemorrhages can persist longer.

Risk Factors and Causes

Trauma

• Abusive head trauma
• Accidental head trauma
• Direct ocular trauma
• Birth trauma

Retinal Vascular Disease

• Diabetic retinopathy
• Hypertensive retinopathy
• Retinal vein occlusion
• Retinal artery macroaneurysm
• Ocular ischemic syndrome

Hematologic Disease

• Leukemia
• Thrombocytopenia
• Severe anemia
• Coagulopathy
• Disseminated intravascular coagulation
• Hemophilia
• Vitamin K deficiency
• Sickle cell disease

Infection

Possible causes include:

• Infective endocarditis
• Sepsis
• CMV retinitis
• Toxoplasmosis
• Malaria

Intracranial Disease

Retinal hemorrhages may occur with:

• Papilledema
• Terson syndrome
• Intracranial hemorrhage
• Ruptured aneurysm
• Severe intracranial hypertension

Terson Syndrome

Terson syndrome refers to intraocular hemorrhage associated with:

• Subarachnoid hemorrhage
• Intracranial hemorrhage
• Severe acute intracranial pressure elevation

Hemorrhage may be:

• Vitreous
• Preretinal
• Intraretinal

Hypertension

Severe hypertension may produce:

• Flame hemorrhages
• Cotton-wool spots
• Hard exudates
• Optic disc edema in malignant hypertension

In children, significant hypertensive retinopathy should prompt evaluation for:

• Renal disease
• Endocrine disease
• Other secondary hypertension causes

Diabetes

Diabetic retinopathy causes:

• Microaneurysms
• Dot-blot hemorrhages
• Venous changes
• Exudates
• Neovascularization in advanced disease

Diabetic retinal hemorrhage is uncommon in very young children because retinopathy generally requires:

Years of hyperglycemic exposure.

Leukemia

Leukemia may produce:

• Flame hemorrhages
• Dot-blot hemorrhages
• White-centered hemorrhages
• Cotton-wool spots
• Venous tortuosity

Mechanisms include:

• Anemia
• Thrombocytopenia
• Hyperviscosity
• Direct infiltration

Sickle Cell Disease

Sickle retinopathy can produce:

• Peripheral hemorrhage
• Salmon-patch hemorrhage
• Neovascularization
• Vitreous hemorrhage

especially in proliferative disease.

Papilledema

Severe papilledema may produce:

• Peripapillary flame hemorrhages
• Splinter hemorrhages
• Cotton-wool spots

The optic disc edema itself is usually the dominant finding.

Valsalva Retinopathy

A sudden rise in intrathoracic or intra-abdominal pressure can rupture superficial retinal capillaries.

Triggers include:

• Heavy lifting
• Vomiting
• Coughing
• Labor
• Straining

Typical finding:

Premacular preretinal/sub-ILM hemorrhage

with sudden painless central visual loss.

Retinal Vein Occlusion

Central Retinal Vein Occlusion

May show:

• Diffuse retinal hemorrhages
• Venous dilation and tortuosity
• Cotton-wool spots
• Disc edema

Branch Retinal Vein Occlusion

Produces:

• Sectoral hemorrhages
• Corresponding venous congestion

Retinal Macroaneurysm

Retinal arterial macroaneurysm can cause hemorrhage at multiple levels:

• Preretinal
• Intraretinal
• Subretinal

This “multilevel” hemorrhage pattern is especially characteristic.

History

Important questions include:

• Sudden or gradual visual loss?
• Floaters?
• Trauma?
• Recent birth?
• Head injury?
• Unexplained bruising?
• Bleeding tendency?
• Fever or infection?
• Diabetes?
• Hypertension?
• Hematologic disease?
• Anticoagulant use?

In pediatric cases, history should be documented:

Precisely and contemporaneously.

Examination

Perform a complete ocular examination including:

• Visual acuity when age appropriate
• Pupils
• Anterior segment
• IOP when appropriate
• Dilated fundus examination
• Indirect ophthalmoscopy

Describing Retinal Hemorrhages

Document:

• Number
• Size
• Shape
• Retinal layer
• Laterality
• Distribution
• Posterior vs peripheral location
• Macular involvement
• Associated retinoschisis
• Associated retinal folds

Documentation in Suspected AHT

High-quality documentation is especially important.

Whenever feasible obtain:

• Wide-field retinal photography
• Detailed drawings
• Written description

Photography is valuable for:

• Multidisciplinary review
• Monitoring resolution
• Medico-legal documentation

but does not replace a complete examination.

Indirect Ophthalmoscopy

Dilated indirect ophthalmoscopy is essential for assessing:

• Peripheral retinal extent
• Hemorrhage number
• Retinoschisis
• Retinal tears
• Retinal detachment

This is particularly important in suspected AHT because peripheral hemorrhages may be missed on limited posterior examination.

OCT

OCT is useful for:

• Macular hemorrhage
• Sub-ILM hemorrhage
• Retinoschisis
• Retinal layer localization
• Macular structural damage

Handheld OCT may be useful in infants when available.

Fundus Photography

Wide-field imaging can document:

• Extent
• Distribution
• Evolution over time

RetCam-type systems are often used in infants and young children.

B-Scan Ultrasonography

Useful when media opacity prevents retinal visualization due to:

• Dense vitreous hemorrhage
• Cataract
• Severe anterior segment opacity

It can assess for:

• Retinal detachment
• Posterior segment mass
• Vitreous hemorrhage

Laboratory Evaluation

Testing should be:

Directed by the clinical context

rather than automatically ordering every possible test.

Common initial studies when systemic bleeding disorder is possible include:

• CBC with platelet count
• PT/INR
• aPTT

Additional Hematologic Testing

When indicated, consider:

• Fibrinogen
• D-dimer
• von Willebrand testing
• Specific clotting factors
• Platelet function studies

usually in consultation with hematology.

Infectious Evaluation

If infection is suspected, investigations depend on the clinical setting and may include:

• Blood cultures
• Inflammatory markers
• Targeted serologies/PCR

Child Protection Evaluation

When AHT is a concern, evaluation may include:

• Pediatric assessment
• Neuroimaging
• Skeletal survey
• Laboratory testing for bleeding disorders
• Social/child-protection team consultation

The exact investigation follows:

Local child-protection protocols.

Important Modern Correction – Metabolic Testing

Disorders such as:

Glutaric aciduria type 1

have historically been discussed as mimics of AHT.

They should not be reflexively tested in every child with retinal hemorrhage.

Metabolic testing is best guided by:

• Clinical phenotype
• Neurologic findings
• Neuroimaging
• Genetics/metabolic consultation

Differential Diagnosis

Important causes include:

• Abusive head trauma
• Accidental trauma
• Birth-related retinal hemorrhage
• Coagulopathy
• Leukemia
• Severe anemia
• Retinal vein occlusion
• Hypertensive retinopathy
• Diabetic retinopathy
• Papilledema
• Terson syndrome
• Valsalva retinopathy
• Retinal macroaneurysm
• Infective endocarditis
• Retinal vasculitis

Treatment Principles

There is no treatment directed simply at the presence of blood.

Management focuses on:

1. Treating the underlying cause
2. Protecting vision
3. Preventing complications

Observation

Many retinal hemorrhages resolve spontaneously.

Observation is appropriate when:

• Underlying cause is controlled
• Hemorrhage is not vision-threatening
• No retinal detachment or neovascular complication exists

Hematologic Disease

Treat the systemic disorder appropriately.

Management may include:

• Platelet transfusion
• Packed red blood cells
• Fresh frozen plasma
• Vitamin K
• Specific factor replacement

depending on the underlying condition.

Retinal Vascular Disease

Management depends on cause.

Examples:

• Diabetic retinopathy → anti-VEGF/laser according to stage
• Retinal vein occlusion → anti-VEGF for macular edema ± other treatment
• Proliferative disease → PRP
• Retinal macroaneurysm → observation, laser, or anti-VEGF in selected cases

Valsalva Hemorrhage

Most premacular hemorrhages can be:

Observed

because spontaneous clearing is common.

Large dense premacular hemorrhages may occasionally be treated with:

• Nd:YAG membranotomy in selected appropriate cases
• Vitrectomy if nonclearing or complicated

Vitreous Hemorrhage

Pars plana vitrectomy may be indicated for:

• Nonclearing vitreous hemorrhage
• Retinal detachment
• Traction
• Need to visualize/treat underlying retinal disease

Pediatric Vitreous Hemorrhage

The threshold for intervention may be lower in young children because prolonged visual deprivation can cause:

Amblyopia

especially during critical periods of visual development.

Amblyopia Management

If one eye has prolonged visual deprivation:

• Refractive correction
• Occlusion therapy
• Other amblyopia treatment

may be required once the ocular media are sufficiently clear.

Retinoschisis in AHT

Surgery for traumatic macular retinoschisis is:

Rare and individualized

because intervention itself can damage fragile retinal tissue.

Most management focuses on:

• Systemic stabilization
• Documentation
• Observation of ocular findings

unless a specific surgical indication develops.

Follow-Up

Follow-up depends on:

• Cause
• Hemorrhage severity
• Macular involvement
• Vitreous involvement
• Retinal detachment risk
• Age of patient

Neonatal Hemorrhage

Most uncomplicated birth-related hemorrhages require:

• Observation

Follow-up is particularly appropriate when:

• Macula is involved
• Hemorrhage is dense
• Vitreous hemorrhage is present
• Resolution is uncertain

Pediatric AHT

Serial documentation may help assess:

• Hemorrhage resolution
• Retinoschisis
• Optic nerve injury
• Retinal scar formation
• Visual potential

Prognosis

Prognosis depends primarily on:

The underlying disease rather than the hemorrhage itself.

Small intraretinal hemorrhages often resolve without permanent visual loss.

Poor Prognostic Features

Visual prognosis is worse with:

• Dense premacular hemorrhage
• Vitreous hemorrhage
• Macular retinoschisis
• Retinal detachment
• Optic nerve injury
• Severe retinal ischemia
• Associated cortical visual impairment

Abusive Head Trauma Prognosis

Visual impairment after severe AHT may result from:

• Retinal injury
• Optic atrophy
• Retinal folds/scarring
• Amblyopia
• Cortical/cerebral visual impairment

Neurologic injury may be more important than retinal damage in determining final visual function.

Complications

Possible complications include:

• Vitreous hemorrhage
• Retinal detachment
• Retinoschisis
• Macular scar
• Epiretinal membrane
• Optic atrophy
• Amblyopia
• Strabismus
• Permanent visual loss

Ophthalmology Pearls

• Retinal hemorrhage is a sign, not a diagnosis; interpretation depends on morphology, layer, distribution, age, and systemic context.
• Flame hemorrhages arise in the nerve fiber layer, whereas dot-blot hemorrhages arise in deeper retinal layers.
• Preretinal/sub-ILM hemorrhage may appear boat-shaped and can cause severe central visual loss when premacular.
• White-centered hemorrhages (Roth spots) are nonspecific and are not pathognomonic of infective endocarditis.
• In infants and young children, retinal hemorrhage requires careful consideration of birth trauma, accidental trauma, systemic disease, coagulopathy, and abusive head trauma.
• Retinal findings particularly concerning for AHT include numerous bilateral multilayer hemorrhages extending to the retinal periphery, macular retinoschisis, and perimacular folds, but no single ocular finding proves abuse by itself.
• Suspected AHT requires a multidisciplinary child-protection evaluation, not interpretation of retinal findings in isolation.
• Wide-field photography plus detailed written documentation is highly valuable in suspected pediatric trauma.
• CPR alone generally does not explain extensive multilayer peripheral retinal hemorrhages.
• Birth-related retinal hemorrhages usually resolve spontaneously within days to weeks.
• Dense vitreous hemorrhage in a young child can produce deprivation amblyopia, so prolonged nonclearing hemorrhage may justify earlier vitrectomy.
• In older patients, common etiologies include diabetic retinopathy, retinal vein occlusion, hypertension, retinal macroaneurysm, Valsalva retinopathy, and hematologic disease.
• OCT is particularly useful for localizing premacular hemorrhage, sub-ILM blood, retinoschisis, and macular structural injury.
• Treatment is directed at the underlying cause; most uncomplicated intraretinal hemorrhages themselves require observation rather than direct therapy.
• The visual prognosis depends much more on associated macular, optic nerve, retinal ischemic, or cerebral injury than on the mere presence of hemorrhage.

Ophthalmology – Retinal Break

Basics

Description

A retinal break is a full-thickness defect in the neurosensory retina.

Major types include:

• Horseshoe retinal tear
• Operculated retinal hole
• Atrophic round retinal hole
• Retinal dialysis
• Giant retinal tear

Most occur in the:

Peripheral retina

The principal clinical importance is that a break may permit liquefied vitreous to enter the subretinal space, causing:

Rhegmatogenous retinal detachment (RRD)

Key Clinical Concept

A retinal break itself usually does not reduce central visual acuity.

Symptoms generally arise from:

• Acute posterior vitreous detachment
• Vitreous hemorrhage
• Retinal detachment

The major management question is:

Does this retinal break have enough traction and configuration to justify prophylactic treatment?

Pathophysiology

Retinal breaks arise through two main mechanisms:

Vitreoretinal Traction

Seen particularly with:

• Acute posterior vitreous detachment
• Horseshoe tears
• Retinal dialysis
• Giant retinal tears

Retinal Atrophy

Seen particularly with:

• Round atrophic holes
• Lattice degeneration

Posterior Vitreous Detachment

The most important acquired mechanism is:

Acute PVD with persistent focal vitreoretinal adhesion

As the posterior vitreous separates, traction may pull sufficiently hard on the peripheral retina to create:

A horseshoe tear

This is the classic high-risk retinal break.

Horseshoe Tear

A horseshoe or flap tear is caused by:

Persistent vitreous traction on the apex of a retinal flap

Typical features:

• U- or horseshoe-shaped defect
• Vitreous remains attached to the flap
• Apex usually points posteriorly
• Associated acute flashes/floaters common

These tears have a significant risk of progression to RRD if symptomatic and untreated.

Operculated Retinal Hole

An operculated hole occurs when vitreous traction avulses a small piece of retina.

The detached retinal tissue becomes an:

Operculum

floating anterior to the retinal hole.

Because traction may have been released, the risk of RRD is often lower than with an actively tractional horseshoe tear.

Atrophic Round Hole

These result from:

Peripheral retinal thinning rather than acute vitreous traction

They are commonly associated with:

• Lattice degeneration
• Peripheral retinal degeneration

Most isolated asymptomatic atrophic holes have a:

Low risk of causing retinal detachment

Retinal Dialysis

A retinal dialysis is a circumferential retinal break at the:

Ora serrata

It represents separation of the retina from its anterior attachment.

Common associations include:

• Blunt ocular trauma
• Younger patients
• Inferotemporal location in traumatic cases

Dialysis may remain occult for a prolonged period before producing RRD.

Giant Retinal Tear

A giant retinal tear is a circumferential full-thickness break involving:

≥90° of retinal circumference

It is associated with:

• High myopia
• Trauma
• Stickler syndrome
• Marfan syndrome
• Other vitreoretinopathies

It carries a high risk of:

• Extensive RRD
• Proliferative vitreoretinopathy

and usually requires vitreoretinal surgery.

Epidemiology

Peripheral retinal breaks are relatively common in the population.

Many remain:

• Asymptomatic
• Stable
• Never associated with retinal detachment

The risk varies greatly according to:

• Break type
• Symptoms
• Vitreous traction
• Subretinal fluid
• Patient risk factors

Retinal Tears in Acute Symptomatic PVD

An acute symptomatic PVD carries a meaningful risk of associated retinal tear.

Approximately:

8–15%

of patients with acute symptomatic PVD may have a retinal tear identified on initial examination, depending on the population studied.

A small additional proportion develop:

Delayed retinal tears

after an initially negative examination.

Risk Factors

Important risk factors include:

• Acute symptomatic PVD
• High myopia
• Lattice degeneration
• Increasing age
• Cataract surgery
• Aphakia
• Ocular trauma
• Previous retinal tear
• Previous RRD
• Fellow-eye RRD
• Family history of retinal detachment

Genetic / Syndromic Risk Factors

Disorders associated with increased retinal break/RRD risk include:

• Stickler syndrome
• Marfan syndrome
• Wagner syndrome
• Selected collagen disorders
• Certain inherited vitreoretinopathies

Stickler syndrome is especially important because of its very high lifetime RRD risk.

Symptoms

Symptoms usually reflect vitreous traction rather than the retinal break itself.

Typical symptoms include:

• Flashes (photopsias)
• New floaters
• Shower of black spots
• Cobwebs
• Sudden vitreous haze

A retinal detachment may cause:

• Curtain
• Shadow
• Peripheral field loss
• Reduced central vision if macula becomes involved

Photopsias

Flashes are caused by:

Mechanical vitreoretinal traction stimulating the retina

They are often:

• Brief
• Peripheral
• More noticeable in darkness
• Triggered by eye movement

Floaters

New floaters may represent:

• Vitreous condensations
• Weiss ring
• Pigment cells
• Blood

A sudden shower of floaters is particularly concerning for:

• Retinal tear
• Vitreous hemorrhage

Vitreous Hemorrhage

Vitreous hemorrhage in the setting of acute PVD is a major red flag.

Possible mechanisms include:

• Tearing of a retinal vessel across a flap tear
• Retinal break with vascular injury

An acute PVD with vitreous hemorrhage carries a:

Substantially increased likelihood of retinal tear

and requires meticulous retinal examination.

Shafer Sign

Shafer sign, also called:

Tobacco dust

refers to pigmented cells in the anterior vitreous.

It strongly suggests:

A retinal break in the setting of acute PVD

until proven otherwise.

Weiss Ring

A Weiss ring indicates separation of posterior vitreous from the:

Optic disc

It supports the diagnosis of PVD.

However:

A Weiss ring does not prove that all peripheral vitreoretinal attachments have released.

A retinal tear may still be present.

Diagnosis

Diagnosis requires:

Careful dilated examination of the peripheral retina

The key examination is:

Indirect ophthalmoscopy with scleral depression whenever possible

Why Scleral Depression Matters

Many tears occur:

• Near the vitreous base
• In the far periphery
• Anterior to the equator

and may be missed without scleral depression.

A negative posterior pole examination does:

Not exclude a peripheral retinal tear.

Examination

Assess:

• Visual acuity
• Pupils
• Vitreous
• Shafer sign
• Vitreous hemorrhage
• PVD
• Peripheral retina
• Subretinal fluid
• Fellow eye

Retinal Hole Appearance

Atrophic retinal holes are usually:

• Round
• Small
• Flat
• Often within lattice degeneration

They may have:

• Surrounding pigment

suggesting chronicity.

Horseshoe Tear Appearance

A horseshoe tear demonstrates:

• Flap of retina
• Persistent vitreous traction
• Possible bridging vessel

A bridging retinal vessel may predispose to:

Recurrent vitreous hemorrhage

Retinal Dialysis Appearance

Features include:

• Circumferential break at the ora serrata
• Rolled posterior retinal edge
• Possible pigmentation in chronic cases

Carefully ask about:

Remote trauma, even years earlier.

Lattice Degeneration

Lattice degeneration appears as:

• Peripheral retinal thinning
• White vessels
• Pigment
• Crisscrossing white lines
• Associated round holes in some cases

Most lattice degeneration:

Does not require prophylactic treatment.

B-Scan Ultrasonography

B-scan is useful when media opacity prevents adequate retinal visualization, especially with:

• Dense vitreous hemorrhage
• Cataract
• Corneal opacity

It is excellent for detecting:

• Retinal detachment
• PVD
• Vitreous hemorrhage

Important Limitation of B-Scan

B-scan may occasionally suggest a retinal break, but:

It is not sufficiently sensitive to rule out a small peripheral tear.

If dense vitreous hemorrhage obscures the retina, repeat examinations and/or early vitreoretinal intervention may be required depending on risk.

OCT

OCT is useful for:

• Macular hole
• Vitreomacular traction
• Macular involvement of RRD

but:

OCT cannot exclude peripheral retinal tears.

Differential Diagnosis

Important mimics include:

• Chorioretinal scar
• Peripheral retinal degeneration
• Pars plana cyst
• Enclosed oral bay
• Meridional fold
• Vitreoretinal tuft
• White without pressure
• Peripheral cystoid degeneration

White Without Pressure

White without pressure is a peripheral retinal appearance caused by:

• Vitreoretinal interface changes

It may mimic a retinal tear edge but is:

Not itself a full-thickness retinal break.

Treatment Principles

Treatment is directed at:

Preventing progression to rhegmatogenous retinal detachment

Not every retinal break should be treated.

Treatment depends on:

• Symptoms
• Traction
• Break type
• Subretinal fluid
• Fellow-eye history
• Patient risk factors

Symptomatic Horseshoe Tear

An acute symptomatic horseshoe tear should generally receive:

Prompt retinopexy

because untreated symptomatic tractional tears have a significant risk of progressing to RRD.

Laser Retinopexy

Laser photocoagulation is the usual first-line treatment.

Laser burns are applied:

• Around the retinal break
• In multiple contiguous rows
• To create a chorioretinal adhesion

The goal is to prevent fluid from extending through the break into the subretinal space.

Laser Technique Principle

Treatment must completely surround the break.

For very anterior tears:

• Laser should extend sufficiently anteriorly toward the ora serrata

so that the full margins of the break are sealed.

Incomplete treatment is an important cause of failure.

Cryotherapy

Cryotherapy is an alternative when:

• Break is very anterior
• Media opacity limits laser
• Laser delivery is technically difficult

It creates:

Trans-scleral chorioretinal adhesion

around the break.

Laser vs Cryotherapy

Laser is often preferred when feasible because it causes:

• Less inflammation
• More precise treatment

Cryotherapy remains useful for selected peripheral breaks.

Treatment of Operculated Holes

Asymptomatic operculated holes usually:

Do not require treatment

if there is no:

• Persistent traction
• Subretinal fluid
• High-risk clinical context

Symptomatic cases are individualized.

Treatment of Atrophic Holes

Most asymptomatic atrophic round holes are:

Observed

especially if:

• No subretinal fluid
• No progressive retinal detachment
• No particularly high-risk syndrome

Atrophic Holes in Lattice

Atrophic holes within lattice degeneration are commonly:

Observed without prophylactic laser

unless there are additional high-risk circumstances.

Lattice Degeneration

Routine prophylactic treatment of lattice degeneration alone is:

Not recommended for most patients.

Treatment may be considered selectively when risk is unusually high.

High-Risk Situations for Prophylaxis

Prophylactic treatment may be considered in selected eyes with:

• Symptomatic tractional tear
• Subclinical retinal detachment around a break
• Fellow-eye giant retinal tear
• Certain high-risk hereditary vitreoretinopathies
• Selected eyes before procedures when specific retinal pathology is present

The decision should be individualized.

Fellow Eye After RRD

A history of retinal detachment in the fellow eye increases risk.

However:

Prophylactic laser is not automatically indicated for every peripheral lesion in the fellow eye.

The morphology and risk profile matter.

Retinal Dialysis Treatment

A retinal dialysis without significant detachment may be treated with:

• Laser
• Cryotherapy

Once an RRD is present, repair often requires:

• Scleral buckle
• Vitrectomy in selected cases
• Combined approaches

When RRD Is Already Present

Once fluid has progressed to a clinically significant retinal detachment, simple laser around the break is generally insufficient.

Treatment may involve:

• Pneumatic retinopexy
• Scleral buckle
• Pars plana vitrectomy
• Combined surgery

depending on:

• Break number
• Location
• Lens status
• PVR
• Extent of detachment

Subclinical Retinal Detachment

A small amount of localized subretinal fluid around a tear may sometimes be barricaded with laser when:

• It is limited
• Nonprogressive
• Anatomically suitable

Progressive detachment generally requires surgical repair.

Acute Symptomatic PVD With No Tear

If no tear is found initially:

• Educate about warning symptoms
• Arrange follow-up according to risk

A common approach is repeat examination in approximately:

4–6 weeks

with earlier review in high-risk cases.

High-Risk Follow-Up

Closer surveillance is warranted with:

• Vitreous hemorrhage
• Retinal hemorrhage
• Shafer sign
• Lattice degeneration
• High myopia
• Prior RRD
• Fellow-eye retinal tear/RD
• Recent cataract surgery
• Trauma

Delayed Retinal Tears

A small proportion of patients develop:

New or initially occult retinal tears after the first examination

This is why symptom education and appropriate follow-up are essential.

Patient Education

Patients should seek urgent assessment for:

• Sudden increase in floaters
• New flashes
• Shower of black dots
• Curtain or shadow
• New peripheral field defect
• Sudden reduction in vision

These may indicate:

• New retinal tear
• Vitreous hemorrhage
• Retinal detachment

Myopia and Refractive Surgery

Laser refractive surgery changes:

Corneal refractive power

but does not shorten an elongated myopic eye.

Therefore highly myopic patients remain at increased risk for:

• Retinal tears
• RRD

after LASIK, PRK, or similar procedures.

Cataract Surgery

Pseudophakia is associated with an increased long-term risk of:

Rhegmatogenous retinal detachment

especially in:

• Younger patients
• Men
• High myopes
• Eyes with posterior capsular rupture
• Certain peripheral retinal abnormalities

New flashes/floaters after cataract surgery require retinal evaluation.

Trauma

Blunt trauma may cause:

• Retinal dialysis
• Horseshoe tear
• Giant retinal tear

The retinal break or detachment may present:

Weeks to years later

so remote trauma remains relevant.

Prevention

Most PVD-associated retinal tears cannot be prevented.

The most effective strategy is:

Prompt recognition and treatment of high-risk retinal breaks before RRD develops.

Protective eyewear can reduce traumatic retinal injury risk.

Prognosis

A properly treated retinal tear usually has:

Excellent anatomic prognosis

with a high rate of successful retinal detachment prevention.

However, retinopexy does not prevent:

• New retinal tears elsewhere
• Continued PVD evolution
• Every possible RRD

Failure After Retinopexy

Reasons include:

• Incomplete laser around the tear
• Inadequate anterior treatment
• Continued vitreoretinal traction
• Extension of the original tear
• Development of a new tear
• Established subretinal fluid beyond the barricade

Complications of Laser/Cryotherapy

Potential complications include:

• Mild transient inflammation
• Small retinal hemorrhage
• Epiretinal membrane
• Rare choroidal effusion
• Rare inadvertent macular laser injury

Clinically significant complications are uncommon when treatment is properly performed.

Epiretinal Membrane

ERM may develop after:

• PVD
• Retinal tear
• RRD

It has historically been attributed to laser in some cases, but much of the risk is associated with the underlying vitreoretinal event itself.

Ophthalmology Pearls

• A retinal break is a full-thickness defect in the neurosensory retina that may allow fluid into the subretinal space and cause rhegmatogenous retinal detachment.
• The major types are horseshoe tears, operculated holes, atrophic holes, retinal dialyses, and giant retinal tears.
• Horseshoe tears are caused by persistent vitreoretinal traction and are the classic high-risk break.
• Acute symptomatic PVD causes flashes and floaters; approximately 8–15% may have an associated retinal tear on initial assessment.
• Shafer sign (tobacco dust) and vitreous hemorrhage are major warning signs for a retinal tear.
• A Weiss ring confirms vitreopapillary separation but does not exclude persistent peripheral vitreoretinal traction or retinal tears.
• The key examination is dilated indirect ophthalmoscopy with scleral depression whenever possible.
• OCT does not exclude a peripheral tear, and B-scan is mainly useful when media opacity prevents direct examination.
• Acute symptomatic horseshoe tears generally require prompt laser retinopexy or cryotherapy.
• Most asymptomatic atrophic holes and operculated holes without traction can be observed.
• Routine prophylactic laser for lattice degeneration alone is not recommended in most patients.
• Laser treatment must completely surround the break, including adequate anterior coverage for very peripheral tears.
• Retinal dialysis is classically associated with blunt trauma and may present long after the injury.
• A giant retinal tear involves ≥90° of retinal circumference and usually requires vitreoretinal surgical management.
• After an acute symptomatic PVD with no tear found, repeat examination is commonly performed around 4–6 weeks, sooner when high-risk features are present.
• New flashes, sudden increase in floaters, curtain/shadow, field loss, or reduced vision require urgent reassessment.
• Successful retinopexy prevents most detachments from the treated break but does not prevent new retinal tears elsewhere.

Ophthalmology – Retinoblastoma

Basics

Description

Retinoblastoma (RB) is the most common primary intraocular malignancy of childhood.

It arises from the developing retina and usually presents before:

5 years of age, most commonly in the first few years of life.

It may be:

• Unilateral
• Bilateral
• Unifocal
• Multifocal
• Heritable or nonheritable

The most important presenting signs are:

• Leukocoria
• Strabismus

Any child with either finding requires:

Urgent dilated ophthalmic examination.

Key Clinical Priorities

Management follows three priorities:

1. Save life
2. Save the eye
3. Preserve useful vision

Cosmesis is secondary to these goals.

Epidemiology

Retinoblastoma occurs in approximately:

1 in 15,000–20,000 live births

Worldwide, several thousand children are diagnosed each year.

In high-resource settings, survival exceeds:

95%

when disease is confined to the eye and treated promptly.

Survival remains substantially lower in regions where diagnosis is delayed and extraocular disease is more common.

Age at Presentation

Typical patterns:

Bilateral/Heritable RB

Presents:

• Earlier
• Often during infancy
• Frequently multifocal

Unilateral/Nonheritable RB

Presents:

• Somewhat later
• Usually as a single tumor

Genetics

The fundamental genetic abnormality involves:

RB1 tumor suppressor gene

located at:

Chromosome 13q14

Knudson Two-Hit Hypothesis

Retinoblastoma provided the classic model for the:

Two-hit hypothesis

Both copies of RB1 must be functionally inactivated in a retinal precursor cell for tumor formation.

Heritable Retinoblastoma

Heritable disease involves a pathogenic germline RB1 variant.

These children have the first “hit” in all cells and require only a second somatic mutation in a retinal cell.

Features include:

• Usually bilateral disease
• Often multifocal tumors
• Earlier presentation
• Increased risk of trilateral retinoblastoma
• Increased lifelong risk of second primary malignancies

Important Modern Genetic Point

Not all unilateral retinoblastoma is nonheritable.

Approximately:

10–15% of children with apparently unilateral RB may carry a germline RB1 pathogenic variant

Therefore:

Genetic counseling and RB1 testing should be offered to essentially all affected children when available.

Nonheritable Retinoblastoma

In nonheritable disease:

• Both RB1 hits occur within the tumor
• Disease is usually unilateral and unifocal
• The mutation is not present throughout the body

However, mosaic germline disease can complicate classification.

Family History

Only a minority of patients have an obvious family history.

A negative family history does:

Not exclude heritable retinoblastoma

because germline mutations may arise de novo.

Inheritance

Heritable RB follows an:

Autosomal dominant cancer predisposition pattern

with high but incomplete penetrance depending on the variant.

An affected individual with a germline RB1 variant may transmit the variant to:

50% of offspring.

Genetic Counseling

Families should receive counseling regarding:

• Germline testing
• Recurrence risk
• Testing of parents and siblings
• Future pregnancy options
• Preimplantation genetic testing when desired
• Prenatal genetic diagnosis when appropriate

Modern counseling should support reproductive choice rather than recommend avoidance of pregnancy.

Prenatal Considerations

In a family with a known pathogenic RB1 variant, options may include:

• Prenatal genetic testing
• Preimplantation genetic testing
• Targeted fetal imaging in selected high-risk pregnancies

Fetal ultrasound alone is:

Not sufficiently sensitive to exclude retinoblastoma.

Delivery planning and prompt postnatal ophthalmic examination are more important.

Newborn Screening in High-Risk Families

Infants with:

• Known familial RB1 mutation
• A parent with heritable retinoblastoma
• A sibling with heritable disease

should undergo:

Prompt ophthalmic examination after birth

often within the first days to weeks of life depending on risk and local protocol.

13q Deletion Syndrome

Large deletions involving chromosome 13q may include:

RB1

and produce retinoblastoma associated with developmental abnormalities.

Features may include:

• Developmental delay
• Growth abnormalities
• Craniofacial dysmorphism
• Limb abnormalities

This should prompt:

Clinical genetics evaluation.

Pathophysiology

Loss of functional RB1 disrupts:

• Cell-cycle regulation
• Retinal differentiation
• Control of proliferation

allowing malignant retinal cells to proliferate.

Histology

Retinoblastoma is composed of:

• Small round blue tumor cells
• Hyperchromatic nuclei
• Scant cytoplasm
• Variable necrosis and calcification

Flexner-Wintersteiner Rosettes

A classic sign of photoreceptor differentiation is:

Flexner-Wintersteiner rosettes

These consist of tumor cells arranged around:

• A central lumen

They are characteristic but not present in every tumor.

Homer Wright Rosettes

Homer Wright-type rosettes may also be seen, reflecting:

• Neuroblastic differentiation

but are less specific.

Calcification

Retinoblastoma commonly contains:

Intratumoral calcification

This is an important imaging clue.

Growth Patterns

Retinoblastoma may grow:

Endophytically

Toward:

• Vitreous cavity

Often associated with:

• Vitreous seeds

Exophytically

Toward:

• Subretinal space

Often associated with:

• Exudative retinal detachment
• Subretinal seeds

Diffuse Infiltrating

A flat infiltrative pattern that may mimic:

• Uveitis
• Endophthalmitis
• Retinal detachment

Presenting Features

The two most common presenting signs are:

Leukocoria

White pupillary reflex

This is the most common presentation.

Strabismus

May result from:

• Macular tumor
• Reduced central vision
• Sensory visual loss

Other Presentations

Less common manifestations include:

• Red painful eye
• Secondary glaucoma
• Hyphema
• Pseudohypopyon
• Cataract
• Vitreous hemorrhage
• Orbital cellulitis-like presentation
• Proptosis in advanced extraocular disease

Leukocoria – Differential Diagnosis

Important causes include:

• Retinoblastoma
• Coats disease
• Persistent fetal vasculature
• Cataract
• Retinal detachment
• Toxocariasis
• Familial exudative vitreoretinopathy
• Retinopathy of prematurity

Because retinoblastoma is potentially fatal:

It must be excluded urgently.

Examination

Children usually require:

Examination under anesthesia (EUA)

for complete assessment.

Document:

• Number of tumors
• Tumor size
• Location
• Distance from fovea and disc
• Vitreous seeds
• Subretinal seeds
• Retinal detachment
• Anterior segment involvement

Fundus Appearance

Retinoblastoma typically appears as:

• Creamy white
• Elevated
• Retinal mass

with possible:

• Calcification
• Surface vessels
• Retinal detachment
• Vitreous/subretinal seeding

Ultrasonography

B-scan ultrasonography is highly useful.

It can demonstrate:

• Intraocular mass
• Retinal detachment
• Highly reflective calcification

Calcification strongly supports retinoblastoma in the appropriate clinical setting.

MRI

MRI of the:

Brain and orbits with contrast

is preferred for evaluating:

• Optic nerve involvement
• Extraocular extension
• Intracranial disease
• Trilateral retinoblastoma

CT

CT can demonstrate calcification but is generally:

Avoided when possible

especially in children with heritable RB because ionizing radiation may increase lifetime second-cancer risk.

Ultrasound and MRI usually provide sufficient diagnostic information.

Fundus Photography

Wide-field retinal photography helps document:

• Tumor size
• Location
• Response to treatment
• New lesions

OCT

Handheld or conventional OCT may help assess:

• Small macular lesions
• Foveal anatomy
• Tumor regression
• Treatment-related retinal damage

It is an adjunct rather than the primary diagnostic test.

Fluorescein Angiography

FA may demonstrate:

• Tumor vasculature
• Treatment effects

but is not essential for diagnosis in most cases.

Critical Diagnostic Rule

Do not perform fine-needle aspiration or intraocular biopsy of suspected retinoblastoma.

This can create:

• Extraocular tumor seeding
• Orbital spread
• Potential metastatic risk

Diagnosis is usually established clinically and with imaging.

International Classification of Retinoblastoma

The International Classification of Retinoblastoma (ICRB) groups intraocular disease by likelihood of eye salvage.

Exact definitions vary slightly between classification versions, but the practical framework is:

Group A

Small tumors away from critical structures.

Typically:

• ≤3 mm
• No vitreous or subretinal seeds

These have an excellent eye-salvage prognosis.

Group B

Larger or more posterior tumors but:

• No significant vitreous/subretinal seeding

May include:

• Macular lesions
• Juxtapapillary lesions
• Limited subretinal fluid

Group C

Localized:

• Vitreous seeds
• Subretinal seeds

close to the primary tumor.

Group D

Diffuse or extensive:

• Vitreous seeding
• Subretinal seeding

These eyes are more difficult to salvage.

Group E

Very advanced intraocular disease with features suggesting poor visual potential or increased treatment complexity.

Examples include:

• Tumor occupying much of the globe
• Neovascular glaucoma
• Massive hemorrhage
• Anterior segment involvement
• Extensive retinal detachment
• Other advanced features

Important Staging Distinction

ICRB groups A–E classify:

Intraocular disease and likelihood of eye salvage

They are not the same as:

• AJCC TNM staging
• Histopathologic metastatic-risk staging

AJCC TNM

Modern multidisciplinary care may also use:

AJCC TNM staging

to describe:

• Intraocular extent
• Regional spread
• Metastatic disease

This is particularly important in:

• Extraocular retinoblastoma
• Oncology outcome reporting

Differential Diagnosis

The major differential diagnoses include:

• Coats disease
• Persistent fetal vasculature
• Toxocariasis
• Familial exudative vitreoretinopathy
• Retinopathy of prematurity
• Retinal detachment
• Astrocytic hamartoma
• Medulloepithelioma
• Cataract

Retinoblastoma vs Coats Disease

Retinoblastoma

• White retinal mass
• Calcification common
• Vitreous/subretinal seeds possible

Coats Disease

• Telangiectatic retinal vessels
• Massive yellow lipid exudation
• Exudative retinal detachment
• No true retinal tumor

Coats disease remains one of the classic:

Pseudoretinoblastomas.

Treatment Principles

Management is individualized according to:

• Unilateral vs bilateral disease
• ICRB group
• Tumor number
• Tumor location
• Vitreous/subretinal seeds
• Visual potential
• Germline status
• Extraocular extension

Treatment should be performed in a:

Specialized retinoblastoma center.

Focal Therapy

Focal treatment is most useful for:

• Small tumors
• Residual tumors after chemotherapy
• Recurrent localized disease

Options include:

• Laser photocoagulation/thermotherapy
• Cryotherapy

Laser / Thermotherapy

Laser is often used for:

• Small posterior tumors
• Residual tumor after chemotherapy

It induces:

• Tumor vascular closure
• Thermal destruction

Cryotherapy

Cryotherapy is particularly useful for:

• Small peripheral tumors
• Anterior lesions

It is less suitable for lesions near:

• Fovea
• Optic disc

because of scar-related visual damage.

Systemic Intravenous Chemotherapy

Traditional chemoreduction uses combinations such as:

• Vincristine
• Etoposide
• Carboplatin

Systemic chemotherapy remains important particularly for:

• Bilateral disease
• Multifocal disease
• Very young infants in selected settings
• Extraocular disease
• High-risk histopathology after enucleation
• Patients where systemic coverage is advantageous

It is no longer the only major globe-salvage strategy.

Intra-Arterial Chemotherapy

Intra-arterial chemotherapy (IAC) has transformed retinoblastoma management.

A catheter is placed into the:

Ophthalmic artery

and chemotherapy is delivered directly to the affected eye.

Common agents include:

• Melphalan
• Topotecan
• Carboplatin

IAC Indications

IAC is commonly used for:

• Unilateral Group B–D disease
• Selected advanced eyes
• Recurrent disease
• Eyes poorly responsive to systemic chemotherapy

It may also be used in selected bilateral cases.

Advantages of IAC

Advantages include:

• High intraocular drug concentration
• Reduced systemic exposure
• Excellent globe salvage in many advanced eyes

IAC Complications

Potential complications include:

• Retinal vascular occlusion
• Choroidal ischemia
• Ophthalmic artery injury
• Eyelid edema
• Cranial nerve effects
• Rare systemic vascular complications

It requires an experienced:

Interventional neuroradiology/ocular oncology team.

Intravitreal Chemotherapy

Intravitreal chemotherapy is now a major treatment for:

Vitreous seeds

Common agents include:

• Melphalan
• Topotecan

Safety-Enhanced Injection Technique

Intravitreal injection in retinoblastoma requires specialized techniques to minimize tumor escape, including:

• Tumor-free injection site
• Controlled needle entry
• Cryotherapy to needle tract in some protocols

This should only be performed by:

Experienced retinoblastoma specialists.

Subretinal Chemotherapy

Highly specialized centers may also use:

• Subretinal chemotherapy

for selected persistent subretinal seeds.

This is not routine first-line therapy everywhere.

Enucleation

Enucleation remains essential for advanced eyes with poor visual potential or high-risk features.

Common indications include:

• Many Group E eyes
• Painful blind eye
• Neovascular glaucoma
• Massive tumor
• Anterior segment invasion
• Severe hemorrhage
• Failure of conservative therapy

Enucleation Principle

When enucleation is required, the optic nerve should be removed with:

As long a segment as safely possible

because histopathologic optic nerve invasion affects metastatic risk.

High-Risk Histopathology

After enucleation, pathology should specifically assess for:

• Postlaminar optic nerve invasion
• Massive choroidal invasion
• Scleral invasion
• Extrascleral extension
• Anterior segment invasion

These features may indicate need for:

Adjuvant systemic chemotherapy.

Plaque Radiotherapy

Plaque brachytherapy may be useful for:

• Localized recurrent tumors
• Residual tumors
• Selected tumors refractory to other local therapy

Its role is now more limited than historically.

External Beam Radiotherapy

External beam radiation is now:

Generally avoided whenever possible

because it increases risks of:

• Second primary malignancies
• Orbital/facial growth disturbance
• Cataract
• Radiation retinopathy
• Radiation optic neuropathy

The risk is especially important in:

Heritable RB1 mutation carriers.

Trilateral Retinoblastoma

Children with heritable retinoblastoma have increased risk of an intracranial primitive neuroectodermal tumor, most often:

• Pinealoblastoma

and less commonly a suprasellar tumor.

This combination is called:

Trilateral retinoblastoma

Brain MRI Surveillance

A brain MRI is generally obtained:

At diagnosis

particularly in:

• Bilateral disease
• Known heritable RB
• Very young children

Some centers perform serial MRI screening every several months until approximately age 5 in heritable disease, while practices vary because the optimal surveillance schedule remains debated.

Second Primary Malignancies

Patients with germline RB1 mutations have an increased lifetime risk of cancers such as:

• Osteosarcoma
• Soft-tissue sarcoma
• Melanoma
• Other epithelial and mesenchymal malignancies

Risk is especially increased after:

Ionizing radiation exposure.

Long-Term Survivorship

Heritable RB survivors require:

• Lifelong awareness of second malignancy risk
• Avoidance of unnecessary ionizing radiation
• Appropriate age- and symptom-based cancer surveillance

Routine whole-body imaging is not automatically indicated for every asymptomatic survivor.

Follow-Up of the Eyes

Children require frequent examination during and after treatment.

Early follow-up may be:

• Every few weeks
• Monthly

depending on:

• Tumor activity
• Age
• Treatment modality

Intervals are gradually extended after sustained regression.

Examination Under Anesthesia

EUA is commonly required until the child is sufficiently cooperative for complete office examination.

There is:

No rigid age cutoff

because this depends on:

• Development
• Cooperation
• Tumor complexity

Tumor Regression

Regressed tumors may become:

• Calcified
• Atrophic
• Scar-like

Different regression patterns occur depending on:

• Treatment modality
• Tumor type

A regressed scar still requires surveillance for:

• Recurrence
• New tumors in genetically susceptible children

Retinoma / Retinocytoma

A benign or spontaneously arrested RB1-related lesion called:

Retinoma/retinocytoma

may occur in some germline mutation carriers.

It can appear:

• Gray
• Calcified
• Translucent

and requires surveillance because malignant transformation can rarely occur.

Visual Prognosis

Visual outcome depends strongly on:

• Foveal involvement
• Optic disc involvement
• Tumor size
• Retinal detachment
• Treatment-related retinal injury

Small peripheral tumors may be treated with:

Excellent visual preservation.

Large macular tumors often cause permanent central visual loss despite successful tumor control.

Amblyopia

Children with unilateral or asymmetric disease are at high risk for:

Amblyopia

After tumor control, visual rehabilitation may include:

• Refractive correction
• Occlusion therapy
• Other amblyopia treatment

when safe and appropriate.

Protective Eyewear

Children with one functional eye should use:

Protective polycarbonate eyewear

to reduce trauma risk to the better-seeing eye.

Prognosis

In high-resource settings, intraocular retinoblastoma has an:

Excellent life prognosis

when detected before extraocular spread.

The major threats to survival are:

• Optic nerve extension
• Extrascleral extension
• CNS involvement
• Hematogenous metastasis

Extraocular Retinoblastoma

Extraocular disease may spread to:

• Orbit
• Brain
• Bone
• Bone marrow

This requires aggressive multidisciplinary management with:

• Systemic chemotherapy
• High-dose chemotherapy in selected cases
• Radiotherapy when necessary
• Surgical management

Poor Prognostic Features

Poorer survival is associated with:

• Delayed diagnosis
• Extraocular extension
• Postlaminar optic nerve invasion
• Massive choroidal invasion
• Scleral/extrascleral invasion
• Metastatic disease

Complications

Potential complications include:

• Visual loss
• Loss of the eye
• Amblyopia
• Cataract
• Retinal detachment
• Vitreous hemorrhage
• Glaucoma
• Radiation complications
• Chemotherapy toxicity
• Second primary malignancy
• Trilateral retinoblastoma

Ophthalmology Pearls

• Retinoblastoma is the most common primary intraocular malignancy of childhood.
• The two most common presenting signs are leukocoria and strabismus; either requires urgent dilated examination.
• The disease results from biallelic inactivation of the RB1 tumor suppressor gene on chromosome 13q14.
• Bilateral and multifocal disease should be considered heritable until proven otherwise, but even apparently unilateral RB can carry a germline RB1 mutation.
• Offer genetic counseling and RB1 testing when available because results affect family screening, future pregnancies, trilateral RB risk, and lifelong cancer surveillance.
• Retinoblastoma typically appears as a white retinal mass with calcification, often associated with retinal detachment or vitreous/subretinal seeds.
• B-scan ultrasonography is valuable for detecting calcification; MRI brain/orbits evaluates optic nerve, extraocular, and intracranial disease.
• Avoid routine CT when MRI and ultrasound are sufficient because children—especially germline RB1 carriers—should minimize unnecessary ionizing radiation.
• Never perform intraocular biopsy or fine-needle aspiration of suspected retinoblastoma because of the risk of tumor seeding.
• The ICRB A–E classification estimates intraocular disease severity and likelihood of globe salvage; it is not equivalent to metastatic staging.
• Modern treatment increasingly uses intra-arterial chemotherapy for globe salvage and intravitreal melphalan/topotecan for vitreous seeds.
• Systemic vincristine/etoposide/carboplatin remains important in bilateral, multifocal, extraocular, and selected high-risk disease.
• Enucleation remains the safest treatment for many advanced Group E eyes with poor visual potential or high-risk features.
• Histopathology after enucleation must assess for postlaminar optic nerve invasion, massive choroidal invasion, scleral and extrascleral extension, which may require adjuvant chemotherapy.
• External beam radiotherapy is now largely avoided because of second malignancy risk and orbital/facial growth abnormalities, especially in heritable disease.
• Heritable RB predisposes to trilateral retinoblastoma and lifelong second primary cancers.
• Modern management follows the priorities: save life → save eye → preserve vision.
• Long-term care includes ocular surveillance, amblyopia treatment, protective eyewear when only one eye sees well, genetic counseling, and survivorship monitoring for second malignancies.

Ophthalmology – Coats Disease

Basics

Description

Coats disease is an idiopathic retinal vascular disorder characterized by:

• Retinal telangiectasia
• Aneurysmal retinal vessels
• Breakdown of the blood-retinal barrier
• Massive intraretinal and subretinal lipid exudation
• Progressive exudative retinal detachment in advanced disease

Classic Coats disease is usually:

• Unilateral
• Sporadic
• Nonhereditary
• Seen predominantly in boys and young males
• Unassociated with systemic disease

The major pediatric diagnostic concern is:

Retinoblastoma, because both can present with leukocoria and retinal detachment.

Epidemiology

Most patients present during:

Childhood, often before age 10

but Coats disease can present:

• In adolescence
• In adulthood
• Rarely later in life

Adult-onset disease is often:

• More localized
• Less exudative
• More slowly progressive

than childhood disease.

Sex and Laterality

Typical epidemiologic pattern:

• Strong male predominance
• Unilateral in the great majority of cases

True bilateral classic Coats disease is extremely unusual.

Bilateral Coats-like retinopathy should prompt evaluation for:

• Inherited retinal vascular disorders
• Systemic syndromes
• Other causes of exudative retinopathy

Genetics

Classic Coats disease is generally:

Sporadic and nonhereditary

Somatic abnormalities involving the:

NDP signaling pathway

have been proposed in some cases, supporting a retinal vascular developmental mechanism.

Routine genetic testing is:

Not required for typical unilateral Coats disease.

When to Consider Genetic/Systemic Evaluation

Consider broader evaluation when there is:

• Bilateral retinal telangiectasia/exudation
• Neurologic abnormalities
• Growth abnormalities
• Skeletal or muscular disease
• Strong family history
• Atypical phenotype

Important Coats-like conditions include:

• Coats plus syndrome
• Familial exudative vitreoretinopathy
• Retinopathy of prematurity
• Incontinentia pigmenti
• Facioscapulohumeral muscular dystrophy-associated retinopathy
• Norrie disease-related retinopathy

Pathophysiology

The fundamental abnormality is:

Retinal vascular incompetence

with:

• Telangiectatic capillaries
• Aneurysmal dilatation
• Abnormal endothelial barrier
• Capillary nonperfusion

This leads to leakage of:

• Lipid
• Protein
• Fluid

into the retina and subretinal space.

Retinal Exudation

Chronic vascular leakage causes:

• Intraretinal hard exudates
• Macular exudation
• Subretinal exudation
• Exudative retinal detachment

Lipid accumulation may become extensive and yellow-white.

Retinal Ischemia

Areas of peripheral retinal nonperfusion may coexist with telangiectasia.

Ischemia contributes to:

• Progressive vascular abnormality
• VEGF production
• Rare neovascularization

Distribution

The abnormal vessels most commonly involve:

Temporal peripheral retina

but disease may extend:

• Inferiorly
• Superiorly
• Nasally
• Circumferentially

More extensive disease tends to occur in younger children.

Shields Classification

A commonly used staging system is:

Stage 1

Retinal telangiectasia only

No significant exudation.

Stage 2

Telangiectasia + exudation

Stage 2A

Exudation does not involve the fovea

Stage 2B

Exudation involves the fovea

This distinction is important because foveal involvement markedly worsens visual prognosis.

Stage 3

Telangiectasia + exudation + exudative retinal detachment

Stage 3A

Subtotal retinal detachment

Stage 3B

Total retinal detachment

Some classifications further divide stage 3A according to foveal involvement.

Stage 4

Total retinal detachment + secondary glaucoma

Usually represents advanced disease.

Stage 5

End-stage disease with:

• Blind eye
• Phthisis
• Severe chronic retinal detachment
• Sometimes chronic pain

Clinical Presentation

Typical presenting features include:

• Decreased vision
• Strabismus
• Leukocoria
• Abnormal red reflex
• Occasionally ocular pain in advanced disease

Some patients are discovered incidentally.

Leukocoria

Any child with:

Leukocoria or an abnormal red reflex

requires urgent ophthalmic evaluation.

Important causes include:

• Retinoblastoma
• Coats disease
• Persistent fetal vasculature
• Cataract
• Retinal detachment
• Toxocariasis

Strabismus

Strabismus may develop because of:

• Macular exudation
• Reduced visual acuity
• Sensory disruption

In young children, strabismus may be the first sign noted by parents.

Visual Loss

Reduced vision may result from:

• Foveal exudation
• Macular edema
• Subfoveal lipid
• Exudative retinal detachment
• Macular fibrosis
• Secondary amblyopia

Fundus Findings

Typical examination reveals:

• Telangiectatic retinal vessels
• Aneurysmal vascular dilatations
• Yellow intraretinal lipid exudation
• Peripheral capillary nonperfusion
• Exudative retinal detachment

Telangiectasia

Coats vessels may appear:

• Irregularly dilated
• Aneurysmal
• Light-bulb shaped
• Tortuous

They are often located in the:

Temporal peripheral retina

Hard Exudates

Lipid exudates may form:

• Circinate rings around abnormal vessels
• Dense macular deposits
• Extensive subretinal yellow material

Macular exudation is a major predictor of visual outcome.

Exudative Retinal Detachment

Progressive leakage may produce:

• Localized subretinal fluid
• Bullous subtotal detachment
• Total exudative retinal detachment

No retinal break is required.

Advanced Anterior Segment Findings

Advanced disease may cause:

• Iris neovascularization
• Secondary glaucoma
• Cataract
• Shallow anterior chamber
• Corneal edema

Chronic total retinal detachment may eventually produce:

Phthisis bulbi

Cholesterol Crystals

Advanced cases may occasionally demonstrate:

• Cholesterol crystals in the subretinal space
• Anterior chamber cholesterolosis

These reflect chronic lipid-rich exudation.

Diagnosis

Diagnosis is primarily:

Clinical + multimodal retinal imaging

The most important task is to:

Exclude retinoblastoma before undertaking treatment

in a child with leukocoria or exudative retinal detachment.

Examination Under Anesthesia

Young children may require:

Examination under anesthesia (EUA)

for complete:

• Dilated retinal examination
• Scleral depression
• Photography
• Fluorescein angiography
• Laser or cryotherapy

EUA is especially useful when office examination is incomplete.

Fundus Photography

Wide-field photography is valuable for:

• Baseline documentation
• Mapping telangiectasia
• Monitoring exudation
• Assessing treatment response

Fluorescein Angiography

Wide-field fluorescein angiography is one of the most useful tests in Coats disease.

It demonstrates:

• Telangiectatic vessels
• Aneurysms
• Peripheral nonperfusion
• Late leakage
• Previously occult abnormal vascular beds

FA helps define the area requiring:

Laser ablation.

Optical Coherence Tomography

OCT is particularly useful for macular assessment.

It may demonstrate:

• Intraretinal fluid
• Subretinal fluid
• Hard exudates
• Foveal distortion
• Epiretinal fibrosis

OCT is important for:

Visual prognosis and treatment monitoring.

OCT Angiography

OCTA may demonstrate:

• Abnormal superficial/deep vascular networks
• Capillary nonperfusion

but currently does not replace wide-field FA for mapping peripheral Coats vessels.

Ultrasonography

B-scan ultrasonography is especially important when:

• Dense exudation obscures the fundus
• Total retinal detachment is present
• Retinoblastoma is in the differential

Coats disease typically shows:

• Retinal detachment
• Subretinal exudation

without the classic intratumoral calcification of retinoblastoma.

Important Caveat About Calcification

Absence of calcification:

Does not by itself prove Coats disease

and the diagnosis of retinoblastoma should never be excluded on a single imaging feature.

The entire clinical and imaging picture must be considered.

Differential Diagnosis

The most important differential is:

Retinoblastoma

Other considerations include:

• Familial exudative vitreoretinopathy
• Persistent fetal vasculature
• Retinopathy of prematurity
• Retinal hemangioblastoma
• Retinal vasoproliferative tumor
• Toxocariasis
• Norrie disease
• Incontinentia pigmenti
• Retinal detachment of another cause
• Radiation retinopathy
• Severe retinal vasculitis

Coats Disease vs Retinoblastoma

Coats Disease

Typically:

• Male child
• Unilateral
• Telangiectatic retinal vessels
• Massive yellow lipid exudation
• Exudative retinal detachment
• Usually no intraocular calcified tumor

Retinoblastoma

Typically:

• Intraocular retinal mass
• Calcification common
• Tumor-associated retinal detachment
• Vitreous or subretinal seeds may be present

Because missing retinoblastoma has major consequences:

Any diagnostic uncertainty warrants evaluation by an ocular oncology or pediatric retinal specialist.

Coats Disease vs FEVR

Familial exudative vitreoretinopathy tends to show:

• Bilateral disease
• Peripheral avascular retina
• Retinal dragging
• Falx folds
• Family history in some patients

Classic Coats disease is overwhelmingly:

Ophthalmology – Relative Afferent Pupillary Defect (RAPD)

Basics

Description

A relative afferent pupillary defect (RAPD) is an asymmetry in the pupillary light response caused by unequal afferent visual input from the two eyes.

It is detected with the:

Swinging flashlight test

and indicates asymmetric dysfunction somewhere in the:

• Retina
• Optic nerve
• Optic chiasm in selected asymmetric lesions
• Optic tract in selected lesions

The older term:

Marcus Gunn pupil

is still encountered, but RAPD is preferred.

Key Clinical Concept

An RAPD is not primarily a disorder of the pupil itself.

It is a sign of:

Asymmetric afferent visual pathway dysfunction

When light is moved from the better eye to the more affected eye, the total afferent signal reaching the pretectal nuclei falls.

As a result:

Both pupils constrict less or relatively dilate

even though the light is now shining directly into one eye.

Normal Pupillary Light Reflex

The afferent pathway is:

Retina → optic nerve → chiasm → optic tract → pretectal nuclei

From the pretectal nuclei, signals project bilaterally to:

• Edinger-Westphal nuclei

The efferent pathway is:

CN III → ciliary ganglion → short ciliary nerves → iris sphincter

Because pretectal output is bilateral, light entering one normal eye normally causes:

• Direct constriction of that pupil
• Consensual constriction of the opposite pupil

What an RAPD Means

An RAPD indicates that one eye provides:

Less afferent pupillary input than the other

It therefore depends on:

Inter-eye asymmetry

rather than absolute visual function.

Important Consequence

A patient with severe bilateral but symmetric optic neuropathy may have:

No RAPD

because both afferent pathways are equally impaired.

Conversely, a patient with normal or near-normal visual acuity may have an RAPD if there is:

• Significant peripheral retinal disease
• Optic nerve dysfunction

RAPD Is a Relative Sign

The defect is named according to the eye with:

Less afferent input

For example:

Left RAPD

means light entering the left eye produces less pupillary constriction than light entering the right eye.

Pathophysiology

The pupillary light reflex depends mainly on:

• Retinal ganglion cells
• Their axons within the optic nerve
• Pretectal projections

A unilateral or asymmetric lesion reduces the neural signal generated by illumination of that eye.

When the light swings from the normal eye to the affected eye:

Both pupils appear to dilate because afferent input has decreased.

RAPD vs Efferent Pupillary Defect

An isolated efferent problem such as:

• CN III palsy
• Pharmacologic mydriasis
• Iris sphincter damage

does not itself create an RAPD.

This is because the swinging flashlight test compares:

Afferent input from each eye

rather than the ability of one pupil to constrict.

Anisocoria and RAPD

An RAPD does not require anisocoria.

Many patients with an RAPD have:

Equal pupil sizes at rest.

Likewise:

Anisocoria does not imply an RAPD.

Major Causes

The most common causes are:

• Optic neuropathy
• Severe asymmetric retinal disease

Optic Nerve Causes

Optic nerve disease is the classic cause.

Examples include:

• Optic neuritis
• NAION
• Arteritic anterior ischemic optic neuropathy
• Compressive optic neuropathy
• Traumatic optic neuropathy
• Infiltrative optic neuropathy
• Radiation optic neuropathy
• Advanced asymmetric glaucoma
• Toxic/nutritional optic neuropathy if asymmetric
• Hereditary optic neuropathy during asymmetric stages

Optic Neuritis

Typical findings include:

• Acute/subacute monocular visual loss
• Reduced color vision
• Contrast loss
• Pain with eye movement
• Central or cecocentral field defect
• RAPD if unilateral or asymmetric

The optic disc may initially be:

• Normal
• Mildly swollen

Ischemic Optic Neuropathy

Both:

• NAION
• AAION

typically produce an RAPD when unilateral.

In an older patient with:

• Sudden visual loss
• RAPD
• Pale disc edema
• GCA symptoms

arteritic ischemic optic neuropathy must be considered urgently.

Compressive Optic Neuropathy

A slowly progressive RAPD may occur with:

• Optic nerve sheath meningioma
• Orbital mass
• Pituitary/parasellar tumor
• Intracranial mass
• Thyroid orbitopathy with apical compression

Associated findings may include:

• Dyschromatopsia
• Field loss
• Optic pallor
• Proptosis
• Motility abnormalities

Glaucoma

Glaucoma can produce an RAPD when damage is:

Significantly asymmetric

The RAPD generally corresponds to the eye with greater:

• RNFL loss
• Visual field damage
• Ganglion cell loss

Early symmetric glaucoma usually does not produce one.

Retinal Causes

Retinal disease must generally be:

Extensive or markedly asymmetric

to produce an RAPD.

Important examples include:

• Central retinal artery occlusion
• Large branch retinal artery occlusion
• Extensive retinal detachment
• Severe retinal ischemia
• Advanced asymmetric retinal dystrophy
• Severe asymmetric retinal vascular occlusion

Central Retinal Artery Occlusion

CRAO commonly produces a:

Dense RAPD

because a large proportion of the inner retinal circulation and ganglion cell function is abruptly lost.

This may be present even before classic funduscopic findings are fully developed.

Retinal Detachment

A large retinal detachment can produce an RAPD, particularly if:

• The macula is detached
• A large retinal area is involved

The magnitude generally reflects:

Extent of functioning retinal loss.

Macular Disease

Isolated macular disease usually produces:

• Reduced central acuity
• Metamorphopsia
• Central scotoma

but often little or no RAPD unless disease is:

Severe and markedly asymmetric.

This can help distinguish some maculopathies from optic neuropathy.

Chiasmal Disease

Chiasmal lesions usually affect both eyes, but an RAPD may occur when damage is:

Asymmetric

Examples include:

• Pituitary mass
• Craniopharyngioma
• Other parasellar lesions

Visual fields are especially important for localization.

Optic Tract Lesions

An optic tract lesion may produce a:

Contralateral RAPD

because the contralateral eye contributes more crossed nasal retinal fibers to the affected tract.

This is sometimes called:

Wernicke hemianopic pupil

although the full classic phenomenon is rarely tested clinically.

Associated visual field finding:

Contralateral homonymous hemianopia

Bilateral Disease

No RAPD may be present when disease is bilaterally symmetric, including:

• Bilateral optic neuritis
• Bilateral advanced glaucoma
• Bilateral toxic optic neuropathy
• Bilateral hereditary optic neuropathy

Thus:

Absence of RAPD does not mean the afferent visual pathways are normal.

Media Opacity

A major examination pearl:

Typical cataract does not produce an RAPD in the cataractous eye.

This is because enough light generally reaches the retina to generate the pupillary response.

Dense Cataract Nuance

Very dense asymmetric media opacity can alter pupillary responses in complex ways, but an RAPD attributable simply to ordinary cataract should be viewed with caution.

If a patient with cataract has an RAPD in that eye, look for:

• Optic neuropathy
• Retinal disease
• Advanced glaucoma

rather than assuming the cataract is responsible.

Vitreous Hemorrhage

Very dense vitreous hemorrhage can reduce retinal illumination enough to produce or contribute to an RAPD, particularly when extremely extensive.

However, an unexpectedly large RAPD should prompt consideration of:

• Retinal detachment
• Retinal ischemia
• Optic nerve disease

behind the media opacity.

Amblyopia

Amblyopia generally does not produce a large RAPD.

A small RAPD may occasionally be detected in marked asymmetric amblyopia, but a substantial RAPD should prompt investigation for:

Organic afferent disease.

Clinical History

Ask about:

• Sudden or progressive vision loss
• Color desaturation
• Brightness difference between eyes
• Visual field loss
• Pain with eye movement
• Headache
• Temporal/scalp tenderness
• Jaw claudication
• Trauma
• Previous malignancy
• Radiation therapy
• Neurologic symptoms

Brightness Desaturation

Patients with optic neuropathy may report that light appears:

Dimmer in the affected eye

This can be tested informally by comparing a bright target or light between the two eyes.

Marked brightness asymmetry supports:

Afferent pathway dysfunction

but is subjective.

Red Desaturation

A red target may appear:

• Less saturated
• Darker
• Washed out

in an eye with optic neuropathy.

This is especially useful when visual acuity loss is mild.

Swinging Flashlight Test

This is the standard bedside examination for RAPD.

Examination Technique

The patient should:

• Fixate on a distant target
• Be examined in relatively dim ambient illumination

Use a:

Bright, focused light source

Step 1

Illuminate one eye for approximately:

2–3 seconds

and observe:

• Direct constriction
• Consensual constriction

Step 2

Quickly swing the light to the fellow eye.

Hold for another:

2–3 seconds

and compare the response.

Repeat several times.

Normal Response

When light is moved between two normal eyes:

• Both pupils remain similarly constricted
• There is no systematic relative dilation

Minor hippus may occur.

Positive RAPD

If light is moved from the better eye to the affected eye:

Both pupils constrict less or relatively dilate

because the afferent signal has fallen.

The apparent dilation is often called:

Pupillary escape

although the essential finding is a relative reduction in constriction.

Critical Examination Pearl

The affected pupil does not uniquely dilate.

Because the light reflex projects bilaterally:

Both pupils show the same consensual response to reduced afferent input.

This is why an RAPD can often still be recognized even if one pupil has an efferent abnormality, by observing the fellow functioning pupil.

Avoiding False Results

Common causes of misleading testing include:

• Moving the light too slowly
• Unequal illumination distance
• Shining light obliquely rather than directly
• Allowing accommodation by near fixation
• Severe hippus
• Not waiting long enough in each eye
• Comparing pupils rather than comparing the response to stimulation of each eye

Neutral Density Filter Testing

RAPD can be quantified using:

Neutral density filters

placed over the better eye until pupillary responses become symmetric.

The strength is expressed in:

Log units

This is more objective than simple +1 to +4 grading.

Clinical RAPD Grading

A qualitative system may describe:

• Trace
• 1+
• 2+
• 3+
• 4+

However:

Clinical grading is examiner-dependent and not fully standardized.

Neutral-density quantification is preferable when precise measurement is required.

Automated Pupillometry

Infrared pupillometry can objectively measure:

• Constriction amplitude
• Velocity
• Latency
• Inter-eye differences

It is increasingly useful in:

• Research
• Neuro-ophthalmic assessment

but is not required for routine diagnosis.

Visual Acuity

Measure:

• Distance acuity
• Near acuity

Remember:

Visual acuity does not determine whether an RAPD is present.

A patient with severe macular blur may have no RAPD, whereas one with optic neuropathy and 20/20 acuity may have one.

Color Vision

Test:

• Ishihara plates
• Red desaturation
• Other formal color tests

Dyschromatopsia is especially suggestive of:

Optic nerve dysfunction.

Visual Fields

Automated perimetry helps:

• Quantify functional loss
• Localize disease

Patterns may include:

• Central scotoma
• Arcuate defect
• Altitudinal defect
• Bitemporal hemianopia
• Homonymous hemianopia

OCT

OCT should assess:

• Peripapillary RNFL
• Macular GCIPL/GCC

It can identify structural evidence of:

• Optic neuropathy
• Glaucoma
• Chiasmal disease patterns

However, OCT may be normal early in:

• Acute optic neuritis
• Acute posterior optic neuropathy

Dilated Fundus Examination

Look for:

• Retinal artery occlusion
• Retinal detachment
• Retinal ischemia
• Optic disc edema
• Optic atrophy
• Advanced glaucoma
• Retinal dystrophy

Neuroimaging

An unexplained RAPD with no adequate ocular explanation should prompt investigation for:

Optic nerve or intracranial disease

when clinically appropriate.

MRI

For suspected optic neuropathy or compressive disease, the preferred examination is usually:

MRI brain and orbits with contrast and fat-suppressed orbital sequences

depending on clinical context.

This is especially important for:

• Optic neuritis
• Compressive optic neuropathy
• Infiltrative disease
• Chiasmal lesions

Important Modern Correction

MRI is not automatically mandatory for every RAPD.

If the cause is already clearly established by ocular examination—for example:

• CRAO
• Large retinal detachment
• Advanced asymmetric glaucoma

neuroimaging may not be necessary solely because an RAPD is present.

Imaging is most important when the defect is:

• Unexplained
• Suggestive of optic neuropathy
• Associated with neurologic signs

Giant Cell Arteritis

In an older patient with acute visual loss and RAPD, especially with:

• New headache
• Scalp tenderness
• Jaw claudication
• Constitutional symptoms
• Pale swollen optic disc

consider:

Giant cell arteritis

urgently.

Tests include:

• ESR
• CRP
• Platelet count

Treatment should not be delayed when clinical suspicion is high.

Pediatric Considerations

In preverbal children, an RAPD can provide valuable objective evidence of:

Asymmetric retinal or optic nerve dysfunction

Potential causes include:

• Optic nerve hypoplasia
• Retinal detachment
• Optic pathway tumor
• Traumatic optic neuropathy
• Severe asymmetric retinal disease

A definite RAPD in a child requires explanation.

Differential Diagnosis

The major categories are:

• Optic neuropathy
• Severe asymmetric retinal disease
• Asymmetric chiasmal disease
• Optic tract lesion
• Severe asymmetric glaucoma

Apparent abnormalities from:

• Hippus
• Unequal illumination
• Efferent pupillary defects

should not be mistaken for true RAPD.

Treatment

There is:

No treatment for the RAPD itself.

Treatment is directed at the underlying disorder.

Examples:

• Optic neuritis → appropriate neurologic/neuro-ophthalmic management
• GCA → immediate systemic corticosteroid therapy
• CRAO → acute retinal/stroke evaluation
• Retinal detachment → retinal repair
• Compression → treat mass
• Glaucoma → lower IOP

Follow-Up

Follow-up depends entirely on the underlying disease.

Serial RAPD assessment can help monitor:

• Progression
• Inter-eye asymmetry

but is generally less precise than:

• Visual fields
• OCT
• Visual acuity
• Color testing

for longitudinal monitoring.

Prognosis

An RAPD itself has no independent prognosis.

Outcome depends on:

• Etiology
• Severity
• Duration
• Reversibility of underlying afferent injury

The RAPD may decrease if function improves, but can persist despite partial recovery.

Ophthalmology Pearls

• An RAPD is an objective sign of asymmetric afferent visual pathway dysfunction and always requires an explanation.
• The most common causes are optic neuropathy and severe asymmetric retinal disease.
• On the swinging flashlight test, moving the light from the better eye to the affected eye causes both pupils to constrict less or relatively dilate.
• An RAPD is a relative sign; severe bilateral symmetric optic neuropathy may produce no RAPD.
• Anisocoria is not required for an RAPD, and anisocoria alone does not imply an afferent defect.
• Isolated efferent pupillary abnormalities do not cause RAPD.
• Optic neuritis, ischemic optic neuropathy, compression, traumatic optic neuropathy, and markedly asymmetric glaucoma are classic optic nerve causes.
• CRAO commonly produces a dense RAPD, while a large retinal detachment can also produce one.
• Isolated macular disease usually produces little or no RAPD unless retinal dysfunction is extensive.
• Ordinary cataract does not explain an RAPD in the cataractous eye; look for retinal or optic nerve disease.
• Dense vitreous hemorrhage may affect the response, but a substantial RAPD should prompt evaluation for underlying retinal ischemia, detachment, or optic neuropathy.
• A small RAPD may occasionally occur in severe amblyopia, but a large defect should be considered organic until proven otherwise.
• Brightness and red desaturation are useful bedside signs of optic neuropathy.
• Neutral density filters provide a more objective RAPD measurement than qualitative +1 to +4 grading.
• An unexplained RAPD with a normal retinal examination should raise strong suspicion for optic nerve disease and often warrants MRI of the brain/orbits with dedicated contrast-enhanced fat-suppressed sequences.
• MRI is not automatically necessary when the ocular cause is already obvious, such as CRAO, large retinal detachment, or advanced asymmetric glaucoma.
• In older patients with acute visual loss and RAPD, always consider giant cell arteritis when the history or disc appearance is compatible.

Ophthalmology – Reactive Arthritis (Reiter Syndrome)

Basics

Description

Reactive arthritis (ReA) is an inflammatory seronegative spondyloarthritis that develops after certain genitourinary or gastrointestinal infections.

The traditional term:

Reiter syndrome

is now generally avoided; reactive arthritis is the preferred terminology.

The classic triad is:

• Arthritis
• Urethritis/cervicitis
• Conjunctivitis

However:

Most patients do not present with the complete triad.

Ocular involvement may include:

• Conjunctivitis
• Acute nongranulomatous anterior uveitis
• Episcleritis
• Rare keratitis or posterior-segment inflammation

The ophthalmically important complication is:

Recurrent anterior uveitis, which may threaten vision if inadequately treated.

Classification

Reactive arthritis belongs to the:

Spondyloarthritis spectrum

along with:

• Ankylosing spondylitis / axial spondyloarthritis
• Psoriatic arthritis
• Inflammatory bowel disease-associated arthritis

These disorders share associations with:

• HLA-B27
• Enthesitis
• Sacroiliitis
• Acute anterior uveitis

Epidemiology

Reactive arthritis typically affects:

• Adolescents
• Young adults

Historically, sexually acquired ReA has been reported more often in men.

The true incidence varies considerably according to:

• Population
• Triggering organism
• Diagnostic criteria
• Geographic region

HLA-B27

HLA-B27 is an important susceptibility and prognostic factor, but it is not required for diagnosis.

The frequency of HLA-B27 positivity varies substantially among cohorts and is generally lower than older estimates of 70–90%.

HLA-B27 positivity is associated with:

• More severe disease
• Sacroiliitis
• Recurrent disease
• Higher likelihood of acute anterior uveitis
• Greater risk of chronic spondyloarthritis phenotype

Important Diagnostic Principle

A positive HLA-B27 test:

Does not diagnose reactive arthritis.

A negative result:

Does not exclude it.

Testing is most useful when:

• Uveitis is recurrent
• Axial symptoms are present
• Spondyloarthritis is suspected
• Prognostic information is needed

Etiology

Reactive arthritis usually develops after infection with certain organisms.

The most important are:

Genitourinary

• Chlamydia trachomatis

Enteric

• Salmonella
• Shigella
• Campylobacter
• Yersinia

Other infectious triggers have been reported, but associations are less consistent.

Timing

Symptoms typically begin:

About 1–4 weeks after the triggering infection

The original infection may have:

• Resolved
• Been mild
• Gone unnoticed

by the time arthritis or uveitis appears.

Pathophysiology

Reactive arthritis is not usually caused by active organisms invading the joint.

Instead, it reflects:

Immune-mediated inflammation triggered by infection in a genetically susceptible host

Possible mechanisms include:

• Persistent bacterial antigens
• Innate immune activation
• Abnormal adaptive immune response
• HLA-B27-associated immune dysregulation

Sterile Arthritis

Joint inflammation is usually:

Culture-negative

hence the term:

Reactive arthritis

rather than septic arthritis.

However, septic arthritis must still be excluded when clinically suspected.

Chlamydia-Associated Disease

In Chlamydia-associated ReA, bacterial components may persist within host cells and contribute to prolonged immune activation.

Chlamydia remains one of the most important identifiable triggers of:

Sexually acquired reactive arthritis.

Enteric Reactive Arthritis

Reactive arthritis can follow gastroenteritis caused by:

• Salmonella
• Shigella
• Campylobacter
• Yersinia

The arthritis often begins after gastrointestinal symptoms have already improved.

Risk Factors

Important risk factors include:

• Recent Chlamydia infection
• Recent bacterial gastroenteritis
• HLA-B27
• Prior reactive arthritis
• Features of underlying spondyloarthritis

HIV

Reactive arthritis can occur in people living with HIV.

However, the relationship is complex because:

• Spondyloarthritis phenotypes overlap
• Infection patterns differ
• Effective antiretroviral therapy has altered epidemiology

HIV testing should be performed when clinically indicated, particularly in patients with:

• Sexually transmitted infection risk
• Unexplained systemic inflammatory disease

Systemic Clinical Features

Reactive arthritis typically causes:

Acute asymmetric oligoarthritis

predominantly affecting the:

• Knees
• Ankles
• Feet

Enthesitis

Inflammation at tendon or ligament insertion sites is characteristic.

Common sites include:

• Achilles tendon
• Plantar fascia

This may produce:

• Heel pain
• Achilles tenderness

Dactylitis

Some patients develop:

Dactylitis

or “sausage digit” swelling.

Axial Disease

Possible features include:

• Sacroiliitis
• Inflammatory back pain

Axial involvement is more likely in:

• HLA-B27-positive
• Recurrent/chronic disease

Genitourinary Manifestations

Symptoms may include:

• Dysuria
• Urethral discharge
• Urinary frequency
• Cervicitis

However, Chlamydia infection may be:

Asymptomatic

especially in women.

Mucocutaneous Findings

Characteristic findings include:

• Circinate balanitis
• Painless oral ulcers
• Keratoderma blennorrhagicum

Keratoderma Blennorrhagicum

This consists of:

• Hyperkeratotic
• Psoriasiform
• Sometimes pustular

lesions, commonly involving:

• Soles
• Palms

It may resemble psoriasis.

Ocular Manifestations

Ocular involvement is common enough to be clinically important.

The major manifestations are:

• Conjunctivitis
• Acute anterior uveitis

Less commonly:

• Episcleritis
• Scleritis
• Keratitis
• Posterior-segment inflammation

Conjunctivitis

Conjunctivitis often appears:

Early in the systemic illness

and may be:

• Bilateral
• Mild
• Self-limited

Symptoms include:

• Redness
• Irritation
• Tearing
• Mild discharge

It may resolve before the patient presents with arthritis.

Conjunctivitis Examination

Typical findings include:

• Diffuse conjunctival injection
• Mild papillary or follicular response
• Watery or mucoid discharge

Vision is usually:

Normal

unless another ocular complication is present.

Treatment of Conjunctivitis

Most uncomplicated conjunctivitis requires:

• Preservative-free lubricants
• Cold compresses

Topical antibiotics are not routinely required unless:

• Bacterial conjunctivitis is suspected separately

Acute Anterior Uveitis

The most important ocular manifestation is:

Acute nongranulomatous anterior uveitis

It resembles HLA-B27-associated uveitis seen in other spondyloarthropathies.

Typical Uveitis Pattern

Features include:

• Acute onset
• Usually unilateral at a given episode
• Pain
• Photophobia
• Ciliary injection
• Blurred vision
• Anterior chamber cells and flare

Disease may alternate between eyes over recurrent episodes.

Severe HLA-B27-Type Uveitis

More severe attacks may cause:

• Fibrin
• Hypopyon
• Posterior synechiae
• Marked anterior chamber reaction

A hypopyon in this setting is typically:

Sterile inflammatory material

but infectious endophthalmitis must be excluded when the clinical context is atypical.

Posterior Synechiae

Inflammation may cause adhesions between:

• Iris
• Anterior lens capsule

called:

Posterior synechiae

Cycloplegic/mydriatic therapy helps prevent or break early synechiae.

Uveitic Complications

Recurrent or poorly controlled inflammation may cause:

• Posterior synechiae
• Cataract
• Ocular hypertension
• Secondary glaucoma
• Cystoid macular edema
• Epiretinal membrane
• Vision loss

Keratitis

Corneal involvement is uncommon.

Reported findings include:

• Superficial punctate keratitis
• Peripheral inflammatory keratitis

Persistent focal ulceration should prompt investigation for:

• Infection
• Herpes simplex
• Other immune-mediated corneal disease

rather than automatically attributing it to reactive arthritis.

Diagnosis

Reactive arthritis is primarily a:

Clinical diagnosis

based on:

• Characteristic arthritis
• Compatible preceding infection
• Extra-articular findings

There is:

No single diagnostic laboratory test.

History

Ask about infection within the preceding several weeks.

Genitourinary History

Ask about:

• Dysuria
• Urethral/cervical discharge
• New sexual partner
• Known STI exposure

Gastrointestinal History

Ask about:

• Diarrhea
• Abdominal pain
• Foodborne illness
• Recent travel
• Similar illness among contacts

Musculoskeletal History

Ask about:

• Asymmetric joint swelling
• Knee or ankle pain
• Heel pain
• Morning stiffness
• Low back pain
• Buttock pain

Ophthalmic History

Ask about:

• Red eye
• Photophobia
• Eye pain
• Blurred vision
• Previous uveitis
• Alternating attacks between eyes

A patient with:

Pain + photophobia + reduced vision

requires assessment for uveitis rather than assuming simple conjunctivitis.

Physical Examination

Systemic examination should look for:

• Asymmetric oligoarthritis
• Enthesitis
• Dactylitis
• Sacroiliac tenderness
• Circinate balanitis
• Oral ulcers
• Keratoderma

Ophthalmic Examination

Perform:

• Visual acuity
• Pupils
• Slit-lamp examination
• IOP
• Dilated fundus examination when uveitis is present

Look specifically for:

• Anterior chamber cells
• Flare
• Fibrin
• Hypopyon
• Posterior synechiae
• Macular edema

Laboratory Evaluation

Tests should be targeted according to the suspected trigger and differential diagnosis.

Possible studies include:

• CBC
• CRP
• ESR

These may demonstrate inflammation but are:

Nonspecific.

Chlamydia Testing

The preferred test for suspected genital Chlamydia is:

Nucleic acid amplification testing (NAAT)

using:

• First-catch urine
• Vaginal/cervical swab
• Urethral specimen as appropriate

Gonorrhea Testing

Because sexually transmitted infections may coexist, testing commonly includes:

Neisseria gonorrhoeae NAAT

when sexually acquired disease is suspected.

Stool Testing

If gastrointestinal symptoms are:

• Recent
• Ongoing

stool culture or multiplex PCR may identify an enteric pathogen.

However, by the time arthritis appears, the gastrointestinal infection may already have cleared, so:

A negative stool test does not exclude post-enteric reactive arthritis.

HLA-B27 Testing

Consider HLA-B27 testing when:

• Recurrent anterior uveitis occurs
• Axial symptoms are present
• Diagnosis within the spondyloarthritis spectrum is uncertain
• Prognostic information is useful

It is not a screening test for every red eye or arthritis episode.

HIV and STI Screening

Depending on risk profile, consider:

• HIV testing
• Syphilis testing
• Other STI testing

particularly when Chlamydia-associated reactive arthritis is suspected.

Joint Aspiration

Synovial fluid analysis is important when the differential includes:

• Septic arthritis
• Crystal arthritis

Reactive arthritis usually shows:

• Inflammatory fluid
• Negative bacterial culture

Imaging

Imaging is not required for every acute case.

Depending on symptoms, studies may include:

• Plain radiographs
• Ultrasound
• MRI of sacroiliac joints

MRI is particularly useful when evaluating:

Early inflammatory sacroiliitis.

Differential Diagnosis

Important differentials include:

• Axial spondyloarthritis
• Psoriatic arthritis
• IBD-associated arthritis
• Septic arthritis
• Disseminated gonococcal infection
• Rheumatoid arthritis
• Crystal arthritis
• Lyme disease
• Sarcoidosis
• Behçet disease
• Systemic lupus erythematosus

Ophthalmic Differential Diagnosis

For acute red eye, consider:

• Conjunctivitis
• HLA-B27-associated anterior uveitis from another spondyloarthritis
• HSV/VZV anterior uveitis
• Syphilitic uveitis
• Sarcoid uveitis
• Behçet disease
• Infectious keratitis
• Scleritis

Treatment Principles

Treatment has three components:

1. Treat an active triggering infection when present
2. Control musculoskeletal inflammation
3. Treat ocular inflammation promptly

Antibiotic Treatment – Chlamydia

If active Chlamydia trachomatis infection is identified:

Treat according to current STI guidelines.

The goals are to:

• Eradicate infection
• Prevent transmission
• Prevent reinfection

Sexual partners also require:

• Evaluation
• Appropriate treatment

Antibiotics and Arthritis

An important distinction:

Antibiotics treat the infection, but they do not reliably terminate established reactive arthritis.

For post-enteric reactive arthritis after the infection has resolved:

Routine prolonged antibiotics are not recommended.

Chronic Chlamydia-Associated ReA

Prolonged combination antibiotic regimens have been investigated in selected chronic Chlamydia-associated disease, but this remains a:

Specialist and nonroutine strategy

rather than standard management for all reactive arthritis.

Musculoskeletal Treatment

NSAIDs

First-line treatment for acute arthritis is usually:

NSAID therapy

assuming no contraindication.

Examples include:

• Naproxen
• Ibuprofen
• Celecoxib
• Other appropriate NSAIDs

There is no requirement to use indomethacin specifically.

Local Corticosteroids

For persistent inflammation involving one or a few joints:

Intra-articular corticosteroid injection

can be effective after septic arthritis has been excluded.

Systemic Corticosteroids

A short systemic corticosteroid course may be considered for:

• Severe polyarthritis
• Major extra-articular inflammation

when NSAIDs are inadequate.

DMARD Therapy

Persistent or chronic arthritis may require:

• Sulfasalazine
• Methotrexate

under rheumatology supervision.

Other conventional immunosuppressants are individualized rather than routine first choices.

Biologic Therapy

For chronic refractory spondyloarthritis-like disease, biologic therapy may be considered.

Options include:

• TNF inhibitors

depending on:

• Axial vs peripheral phenotype
• Previous treatment
• Comorbidities

This should be managed by rheumatology.

Treatment of Anterior Uveitis

The standard initial ocular treatment is:

Topical corticosteroid + cycloplegic/mydriatic

Topical Corticosteroid

For significant anterior chamber inflammation, commonly:

Prednisolone acetate 1%

is used frequently initially.

Severe disease may require dosing:

• Hourly while awake

followed by a:

Slow taper according to inflammatory response.

The taper should be based on:

• Anterior chamber cell
• Flare
• Symptoms

rather than a fixed schedule.

Cycloplegia

Options include:

• Cyclopentolate
• Homatropine
• Atropine in severe cases

Cycloplegics:

• Relieve ciliary spasm
• Reduce pain
• Prevent posterior synechiae
• Help break early synechiae

Severe or Refractory Uveitis

If topical therapy is insufficient, treatment may escalate to:

• Periocular corticosteroid
• Systemic corticosteroid
• Steroid-sparing immunomodulatory therapy

depending on:

• Severity
• Recurrence
• Bilateral involvement
• Posterior involvement

Recurrent Uveitis

Frequent recurrent attacks may require coordination between:

• Ophthalmology
• Rheumatology

Systemic therapy used for the underlying spondyloarthritis can sometimes reduce ocular recurrences.

Biologic Therapy and Uveitis

When biologic treatment is required for associated spondyloarthritis, certain monoclonal anti-TNF agents such as:

• Adalimumab
• Infliximab

have evidence for reducing recurrent anterior uveitis.

Not all TNF inhibitors have equivalent efficacy for ocular inflammation.

Monitoring During Uveitis Treatment

Monitor:

• Visual acuity
• Anterior chamber inflammation
• IOP
• Posterior synechiae
• Lens clarity
• Macula

Long-term topical corticosteroids can cause:

• Cataract
• Steroid-induced ocular hypertension/glaucoma

Prognosis

Reactive arthritis is often:

Self-limited

with substantial improvement over:

Several months

However, some patients develop:

• Recurrences
• Persistent arthritis
• Chronic spondyloarthritis

Chronic Disease Risk

Chronicity is more likely with:

• HLA-B27 positivity
• Severe initial disease
• Recurrent attacks
• Sacroiliitis
• Persistent inflammatory symptoms

Ocular Prognosis

Simple conjunctivitis usually has:

Excellent prognosis

Anterior uveitis also generally responds well when treated promptly.

Poorer outcomes are associated with:

• Repeated severe attacks
• Delayed treatment
• Cystoid macular edema
• Cataract
• Secondary glaucoma

Referral

Ophthalmology

Urgent assessment for:

• Photophobia
• Eye pain
• Reduced vision
• Suspected anterior uveitis

Rheumatology

Appropriate for:

• Significant arthritis
• Persistent symptoms
• Sacroiliitis
• Recurrent uveitis
• Suspected chronic spondyloarthritis

Sexual Health / Primary Care

For:

• Chlamydia or gonorrhea testing
• STI treatment
• Partner management

Ophthalmology Pearls

• Reactive arthritis is the preferred term; “Reiter syndrome” is now largely historical terminology.
• The classic triad is arthritis + urethritis/cervicitis + conjunctivitis, but the complete triad is uncommon.
• Major infectious triggers are Chlamydia trachomatis and the enteric organisms Salmonella, Shigella, Campylobacter, and Yersinia.
• Symptoms typically begin 1–4 weeks after the triggering infection, which may already have resolved.
• HLA-B27 is neither required nor diagnostic; it is most useful as a susceptibility and prognostic marker.
• The typical arthritis is asymmetric oligoarthritis of the lower extremities, often accompanied by enthesitis.
• Characteristic systemic findings include circinate balanitis, painless oral ulcers, and keratoderma blennorrhagicum.
• Conjunctivitis is usually an early, mild, self-limited manifestation and may have resolved by the time arthritis is diagnosed.
• The major vision-threatening manifestation is acute nongranulomatous anterior uveitis.
• Reactive-arthritis uveitis usually resembles other HLA-B27 anterior uveitis: acute, painful, photophobic, often unilateral, and sometimes fibrinous or hypopyon-forming.
• Pain, photophobia, and reduced vision in a patient thought to have “conjunctivitis” should prompt slit-lamp examination for anterior uveitis.
• First-line treatment of anterior uveitis is intensive topical corticosteroid plus cycloplegia, with treatment tapered according to clinical response.
• Monitor uveitis patients for posterior synechiae, cataract, steroid-induced IOP elevation, glaucoma, and cystoid macular edema.
• NAAT is preferred for Chlamydia and gonorrhea testing when sexually acquired disease is suspected.
• Treat active Chlamydia infection and sexual partners appropriately, but antibiotics do not reliably cure established reactive arthritis.
• Routine prolonged antibiotics are not recommended for post-enteric reactive arthritis once the gastrointestinal infection has resolved.
• Persistent arthritis may require NSAIDs, intra-articular steroids, sulfasalazine or methotrexate, and occasionally biologic therapy.
• In patients requiring systemic biologic therapy who also have recurrent uveitis, monoclonal anti-TNF agents such as adalimumab or infliximab may reduce ocular recurrences.
• Most patients improve, but a subset develops recurrent uveitis or chronic spondyloarthritis, making coordinated ophthalmology–rheumatology follow-up important.

Classification Reactive arthritis belongs to the: Spondyloarthritis spectrum along with:  Ankylosing spondylitis / axial spondyloarthritis Psoriatic arthritis Inflammatory bowel disease-associated arthritis  These disorders share associations with:  HLA-B27 Enthesitis Sacroiliitis Acute anterior uveitis

Epidemiology Reactive arthritis typically affects:  Adolescents Young adults  Historically, sexually acquired ReA has been reported more often in men. The true incidence varies considerably according to:  Population Triggering organism Diagnostic criteria Geographic region

HLA-B27 HLA-B27 is an important susceptibility and prognostic factor, but it is not required for diagnosis. The frequency of HLA-B27 positivity varies substantially among cohorts and is generally lower than older estimates of 70–90%. HLA-B27 positivity is associated with:  More severe disease Sacroiliitis Recurrent disease Higher likelihood of acute anterior uveitis Greater risk of chronic spondyloarthritis phenotype

Important Diagnostic Principle A positive HLA-B27 test: Does not diagnose reactive arthritis. A negative result: Does not exclude it. Testing is most useful when:  Uveitis is recurrent Axial symptoms are present Spondyloarthritis is suspected Prognostic information is needed

Etiology Reactive arthritis usually develops after infection with certain organisms. The most important are: Genitourinary  Chlamydia trachomatis  Enteric  Salmonella Shigella Campylobacter Yersinia  Other infectious triggers have been reported, but associations are less consistent.

Timing Symptoms typically begin: About 1–4 weeks after the triggering infection The original infection may have:  Resolved Been mild Gone unnoticed  by the time arthritis or uveitis appears.

Pathophysiology Reactive arthritis is not usually caused by active organisms invading the joint. Instead, it reflects: Immune-mediated inflammation triggered by infection in a genetically susceptible host Possible mechanisms include:  Persistent bacterial antigens Innate immune activation Abnormal adaptive immune response HLA-B27-associated immune dysregulation

Sterile Arthritis Joint inflammation is usually: Culture-negative hence the term: Reactive arthritis rather than septic arthritis. However, septic arthritis must still be excluded when clinically suspected.

Chlamydia-Associated Disease In Chlamydia-associated ReA, bacterial components may persist within host cells and contribute to prolonged immune activation. Chlamydia remains one of the most important identifiable triggers of: Sexually acquired reactive arthritis.

Enteric Reactive Arthritis Reactive arthritis can follow gastroenteritis caused by:  Salmonella Shigella Campylobacter Yersinia  The arthritis often begins after gastrointestinal symptoms have already improved.

Risk Factors Important risk factors include:  Recent Chlamydia infection Recent bacterial gastroenteritis HLA-B27 Prior reactive arthritis Features of underlying spondyloarthritis

HIV Reactive arthritis can occur in people living with HIV. However, the relationship is complex because:  Spondyloarthritis phenotypes overlap Infection patterns differ Effective antiretroviral therapy has altered epidemiology  HIV testing should be performed when clinically indicated, particularly in patients with:  Sexually transmitted infection risk Unexplained systemic inflammatory disease

Systemic Clinical Features Reactive arthritis typically causes: Acute asymmetric oligoarthritis predominantly affecting the:  Knees Ankles Feet

Enthesitis Inflammation at tendon or ligament insertion sites is characteristic. Common sites include:  Achilles tendon Plantar fascia  This may produce:  Heel pain Achilles tenderness

Dactylitis Some patients develop: Dactylitis or “sausage digit” swelling.

Axial Disease Possible features include:  Sacroiliitis Inflammatory back pain  Axial involvement is more likely in:  HLA-B27-positive Recurrent/chronic disease

Genitourinary Manifestations Symptoms may include:  Dysuria Urethral discharge Urinary frequency Cervicitis  However, Chlamydia infection may be: Asymptomatic especially in women.

Mucocutaneous Findings Characteristic findings include:  Circinate balanitis Painless oral ulcers Keratoderma blennorrhagicum

Keratoderma Blennorrhagicum This consists of:  Hyperkeratotic Psoriasiform Sometimes pustular  lesions, commonly involving:  Soles Palms  It may resemble psoriasis.

Ocular Manifestations Ocular involvement is common enough to be clinically important. The major manifestations are:  Conjunctivitis Acute anterior uveitis  Less commonly:  Episcleritis Scleritis Keratitis Posterior-segment inflammation

Conjunctivitis Conjunctivitis often appears: Early in the systemic illness and may be:  Bilateral Mild Self-limited  Symptoms include:  Redness Irritation Tearing Mild discharge  It may resolve before the patient presents with arthritis.

Conjunctivitis Examination Typical findings include:  Diffuse conjunctival injection Mild papillary or follicular response Watery or mucoid discharge  Vision is usually: Normal unless another ocular complication is present.

Treatment of Conjunctivitis Most uncomplicated conjunctivitis requires:  Preservative-free lubricants Cold compresses  Topical antibiotics are not routinely required unless:  Bacterial conjunctivitis is suspected separately

Acute Anterior Uveitis The most important ocular manifestation is: Acute nongranulomatous anterior uveitis It resembles HLA-B27-associated uveitis seen in other spondyloarthropathies.

Typical Uveitis Pattern Features include:  Acute onset Usually unilateral at a given episode Pain Photophobia Ciliary injection Blurred vision Anterior chamber cells and flare  Disease may alternate between eyes over recurrent episodes.

Severe HLA-B27-Type Uveitis More severe attacks may cause:  Fibrin Hypopyon Posterior synechiae Marked anterior chamber reaction  A hypopyon in this setting is typically: Sterile inflammatory material but infectious endophthalmitis must be excluded when the clinical context is atypical.

Posterior Synechiae Inflammation may cause adhesions between:  Iris Anterior lens capsule  called: Posterior synechiae Cycloplegic/mydriatic therapy helps prevent or break early synechiae.

Uveitic Complications Recurrent or poorly controlled inflammation may cause:  Posterior synechiae Cataract Ocular hypertension Secondary glaucoma Cystoid macular edema Epiretinal membrane Vision loss

Keratitis Corneal involvement is uncommon. Reported findings include:  Superficial punctate keratitis Peripheral inflammatory keratitis  Persistent focal ulceration should prompt investigation for:  Infection Herpes simplex Other immune-mediated corneal disease  rather than automatically attributing it to reactive arthritis.

Diagnosis Reactive arthritis is primarily a: Clinical diagnosis based on:  Characteristic arthritis Compatible preceding infection Extra-articular findings  There is: No single diagnostic laboratory test.

History Ask about infection within the preceding several weeks. Genitourinary History Ask about:  Dysuria Urethral/cervical discharge New sexual partner Known STI exposure  Gastrointestinal History Ask about:  Diarrhea Abdominal pain Foodborne illness Recent travel Similar illness among contacts

Musculoskeletal History Ask about:  Asymmetric joint swelling Knee or ankle pain Heel pain Morning stiffness Low back pain Buttock pain

Ophthalmic History Ask about:  Red eye Photophobia Eye pain Blurred vision Previous uveitis Alternating attacks between eyes  A patient with: Pain + photophobia + reduced vision requires assessment for uveitis rather than assuming simple conjunctivitis.

Physical Examination Systemic examination should look for:  Asymmetric oligoarthritis Enthesitis Dactylitis Sacroiliac tenderness Circinate balanitis Oral ulcers Keratoderma

Ophthalmic Examination Perform:  Visual acuity Pupils Slit-lamp examination IOP Dilated fundus examination when uveitis is present  Look specifically for:  Anterior chamber cells Flare Fibrin Hypopyon Posterior synechiae Macular edema

Laboratory Evaluation Tests should be targeted according to the suspected trigger and differential diagnosis. Possible studies include:  CBC CRP ESR  These may demonstrate inflammation but are: Nonspecific.

Chlamydia Testing The preferred test for suspected genital Chlamydia is: Nucleic acid amplification testing (NAAT) using:  First-catch urine Vaginal/cervical swab Urethral specimen as appropriate

Gonorrhea Testing Because sexually transmitted infections may coexist, testing commonly includes: Neisseria gonorrhoeae NAAT when sexually acquired disease is suspected.

Stool Testing If gastrointestinal symptoms are:  Recent Ongoing  stool culture or multiplex PCR may identify an enteric pathogen. However, by the time arthritis appears, the gastrointestinal infection may already have cleared, so: A negative stool test does not exclude post-enteric reactive arthritis.

HLA-B27 Testing Consider HLA-B27 testing when:  Recurrent anterior uveitis occurs Axial symptoms are present Diagnosis within the spondyloarthritis spectrum is uncertain Prognostic information is useful  It is not a screening test for every red eye or arthritis episode.

HIV and STI Screening Depending on risk profile, consider:  HIV testing Syphilis testing Other STI testing  particularly when Chlamydia-associated reactive arthritis is suspected.

Joint Aspiration Synovial fluid analysis is important when the differential includes:  Septic arthritis Crystal arthritis  Reactive arthritis usually shows:  Inflammatory fluid Negative bacterial culture

Imaging Imaging is not required for every acute case. Depending on symptoms, studies may include:  Plain radiographs Ultrasound MRI of sacroiliac joints  MRI is particularly useful when evaluating: Early inflammatory sacroiliitis.

Differential Diagnosis Important differentials include:  Axial spondyloarthritis Psoriatic arthritis IBD-associated arthritis Septic arthritis Disseminated gonococcal infection Rheumatoid arthritis Crystal arthritis Lyme disease Sarcoidosis Behçet disease Systemic lupus erythematosus

Ophthalmic Differential Diagnosis For acute red eye, consider:  Conjunctivitis HLA-B27-associated anterior uveitis from another spondyloarthritis HSV/VZV anterior uveitis Syphilitic uveitis Sarcoid uveitis Behçet disease Infectious keratitis Scleritis

Treatment Principles Treatment has three components:  Treat an active triggering infection when present Control musculoskeletal inflammation Treat ocular inflammation promptly

Antibiotic Treatment – Chlamydia If active Chlamydia trachomatis infection is identified: Treat according to current STI guidelines. The goals are to:  Eradicate infection Prevent transmission Prevent reinfection  Sexual partners also require:  Evaluation Appropriate treatment

Antibiotics and Arthritis An important distinction: Antibiotics treat the infection, but they do not reliably terminate established reactive arthritis. For post-enteric reactive arthritis after the infection has resolved: Routine prolonged antibiotics are not recommended.

Chronic Chlamydia-Associated ReA Prolonged combination antibiotic regimens have been investigated in selected chronic Chlamydia-associated disease, but this remains a: Specialist and nonroutine strategy rather than standard management for all reactive arthritis.

Musculoskeletal Treatment NSAIDs First-line treatment for acute arthritis is usually: NSAID therapy assuming no contraindication. Examples include:  Naproxen Ibuprofen Celecoxib Other appropriate NSAIDs  There is no requirement to use indomethacin specifically.

Local Corticosteroids For persistent inflammation involving one or a few joints: Intra-articular corticosteroid injection can be effective after septic arthritis has been excluded.

Systemic Corticosteroids A short systemic corticosteroid course may be considered for:  Severe polyarthritis Major extra-articular inflammation  when NSAIDs are inadequate.

DMARD Therapy Persistent or chronic arthritis may require:  Sulfasalazine Methotrexate  under rheumatology supervision. Other conventional immunosuppressants are individualized rather than routine first choices.

Biologic Therapy For chronic refractory spondyloarthritis-like disease, biologic therapy may be considered. Options include:  TNF inhibitors  depending on:  Axial vs peripheral phenotype Previous treatment Comorbidities  This should be managed by rheumatology.

Treatment of Anterior Uveitis The standard initial ocular treatment is: Topical corticosteroid + cycloplegic/mydriatic

Topical Corticosteroid For significant anterior chamber inflammation, commonly: Prednisolone acetate 1% is used frequently initially. Severe disease may require dosing:  Hourly while awake  followed by a: Slow taper according to inflammatory response. The taper should be based on:  Anterior chamber cell Flare Symptoms  rather than a fixed schedule.

Cycloplegia Options include:  Cyclopentolate Homatropine Atropine in severe cases  Cycloplegics:  Relieve ciliary spasm Reduce pain Prevent posterior synechiae Help break early synechiae

Severe or Refractory Uveitis If topical therapy is insufficient, treatment may escalate to:  Periocular corticosteroid Systemic corticosteroid Steroid-sparing immunomodulatory therapy  depending on:  Severity Recurrence Bilateral involvement Posterior involvement

Recurrent Uveitis Frequent recurrent attacks may require coordination between:  Ophthalmology Rheumatology  Systemic therapy used for the underlying spondyloarthritis can sometimes reduce ocular recurrences.

Biologic Therapy and Uveitis When biologic treatment is required for associated spondyloarthritis, certain monoclonal anti-TNF agents such as:  Adalimumab Infliximab  have evidence for reducing recurrent anterior uveitis. Not all TNF inhibitors have equivalent efficacy for ocular inflammation.

Monitoring During Uveitis Treatment Monitor:  Visual acuity Anterior chamber inflammation IOP Posterior synechiae Lens clarity Macula  Long-term topical corticosteroids can cause:  Cataract Steroid-induced ocular hypertension/glaucoma

Prognosis Reactive arthritis is often: Self-limited with substantial improvement over: Several months However, some patients develop:  Recurrences Persistent arthritis Chronic spondyloarthritis

Chronic Disease Risk Chronicity is more likely with:  HLA-B27 positivity Severe initial disease Recurrent attacks Sacroiliitis Persistent inflammatory symptoms

Ocular Prognosis Simple conjunctivitis usually has: Excellent prognosis Anterior uveitis also generally responds well when treated promptly. Poorer outcomes are associated with:  Repeated severe attacks Delayed treatment Cystoid macular edema Cataract Secondary glaucoma

Referral Ophthalmology Urgent assessment for:  Photophobia Eye pain Reduced vision Suspected anterior uveitis  Rheumatology Appropriate for:  Significant arthritis Persistent symptoms Sacroiliitis Recurrent uveitis Suspected chronic spondyloarthritis  Sexual Health / Primary Care For:  Chlamydia or gonorrhea testing STI treatment Partner management

Ophthalmology Pearls  Reactive arthritis is the preferred term; “Reiter syndrome” is now largely historical terminology. The classic triad is arthritis + urethritis/cervicitis + conjunctivitis, but the complete triad is uncommon. Major infectious triggers are Chlamydia trachomatis and the enteric organisms Salmonella, Shigella, Campylobacter, and Yersinia. Symptoms typically begin 1–4 weeks after the triggering infection, which may already have resolved. HLA-B27 is neither required nor diagnostic; it is most useful as a susceptibility and prognostic marker. The typical arthritis is asymmetric oligoarthritis of the lower extremities, often accompanied by enthesitis. Characteristic systemic findings include circinate balanitis, painless oral ulcers, and keratoderma blennorrhagicum. Conjunctivitis is usually an early, mild, self-limited manifestation and may have resolved by the time arthritis is diagnosed. The major vision-threatening manifestation is acute nongranulomatous anterior uveitis. Reactive-arthritis uveitis usually resembles other HLA-B27 anterior uveitis: acute, painful, photophobic, often unilateral, and sometimes fibrinous or hypopyon-forming. Pain, photophobia, and reduced vision in a patient thought to have “conjunctivitis” should prompt slit-lamp examination for anterior uveitis. First-line treatment of anterior uveitis is intensive topical corticosteroid plus cycloplegia, with treatment tapered according to clinical response. Monitor uveitis patients for posterior synechiae, cataract, steroid-induced IOP elevation, glaucoma, and cystoid macular edema. NAAT is preferred for Chlamydia and gonorrhea testing when sexually acquired disease is suspected. Treat active Chlamydia infection and sexual partners appropriately, but antibiotics do not reliably cure established reactive arthritis. Routine prolonged antibiotics are not recommended for post-enteric reactive arthritis once the gastrointestinal infection has resolved. Persistent arthritis may require NSAIDs, intra-articular steroids, sulfasalazine or methotrexate, and occasionally biologic therapy. In patients requiring systemic biologic therapy who also have recurrent uveitis, monoclonal anti-TNF agents such as adalimumab or infliximab may reduce ocular recurrences. Most patients improve, but a subset develops recurrent uveitis or chronic spondyloarthritis, making coordinated ophthalmology–rheumatology follow-up important.

Ophthalmology – Reis-Bücklers Corneal Dystrophy

Basics

Description

Reis-Bücklers corneal dystrophy (RBCD) is a rare, bilateral, autosomal dominant TGFBI-associated anterior corneal dystrophy characterized by:

• Recurrent painful corneal erosions beginning in childhood
• Progressive replacement/disruption of Bowman layer
• Superficial stromal fibrosis and opacification
• Increasing corneal irregularity
• Progressive reduction in visual acuity

It was historically called:

• Corneal dystrophy of Bowman layer type 1 (CDB1)
• Granular corneal dystrophy type III

The modern preferred term is:

Reis-Bücklers corneal dystrophy

Key Clinical Pattern

The classic sequence is:

Childhood recurrent erosions → honeycomb/geographic anterior corneal opacities → progressive superficial scarring and irregular astigmatism

Pain from erosions may become less prominent with age while visual loss from:

• Scar
• Surface irregularity
• Anterior stromal deposits

becomes increasingly important.

Epidemiology

RBCD is:

• Rare
• Usually familial
• Bilateral
• Often symmetric early but potentially asymmetric in severity

Exact prevalence is unknown.

Genetics

RBCD is caused by pathogenic variants in:

TGFBI

located on:

Chromosome 5q31

The older gene name:

BIGH3

has largely been replaced by TGFBI.

Classic Mutation

The mutation most strongly associated with classic RBCD is:

TGFBI p.Arg124Leu (R124L)

Inheritance is:

Autosomal dominant

with variable expressivity.

TGFBI Protein

TGFBI encodes:

Transforming growth factor beta-induced protein (TGFBIp)

also known as:

Keratoepithelin

Mutant TGFBIp accumulates extracellularly in the cornea and produces several distinct corneal dystrophies depending on the specific variant.

Other TGFBI Corneal Dystrophies

TGFBI mutations are also associated with:

• Thiel-Behnke corneal dystrophy
• Granular corneal dystrophy type 1
• Granular corneal dystrophy type 2
• Lattice corneal dystrophy type 1

Phenotype–genotype correlation is therefore clinically useful.

RBCD vs Thiel-Behnke Genetics

A classic exam distinction:

Reis-Bücklers

Usually:

TGFBI p.Arg124Leu

Thiel-Behnke

Usually:

TGFBI p.Arg555Gln

This is more useful today than older classifications based solely on electron microscopy.

Pathophysiology

Mutant TGFBI protein accumulates in the:

• Subepithelial region
• Bowman layer
• Superficial anterior stroma

Bowman layer becomes:

• Fragmented
• Replaced
• Irregular

This disrupts epithelial adhesion and produces:

Recurrent corneal erosions

Repeated erosions and abnormal wound healing cause:

• Subepithelial fibrosis
• Superficial stromal scarring
• Irregular anterior corneal surface

Histopathology

Typical findings include:

• Disruption or absence of Bowman layer
• Fibrocellular tissue replacing Bowman layer
• Anterior stromal deposition
• Irregular epithelium

With light microscopy, deposits may stain:

Red with Masson trichrome

Electron Microscopy

RBCD classically demonstrates:

Rod-shaped or granular electron-dense deposits

within the superficial cornea.

This contrasts with Thiel-Behnke dystrophy, which characteristically demonstrates:

Curly fibers

on electron microscopy.

Electron microscopy is now rarely required because:

• Clinical phenotype
• Genetic testing

can usually establish the diagnosis.

Onset

Symptoms usually begin during:

The first decade of life

often around preschool or early school age.

Children may present with:

• Photophobia
• Tearing
• Eye rubbing
• Recurrent painful red eye
• Blepharospasm

Clinical Presentation

Early symptoms result primarily from:

Recurrent corneal epithelial erosions

Typical episodes include:

• Severe ocular pain
• Foreign-body sensation
• Photophobia
• Tearing
• Conjunctival injection
• Temporary blurred vision

Episodes may last:

• Hours
• Days
• Occasionally longer

Disease Evolution

With increasing age:

• Erosions may become less frequent
• Superficial opacification increases
• Corneal surface becomes more irregular
• Best-corrected vision declines

By adolescence or adulthood, visual symptoms may be dominated by:

• Haze
• Irregular astigmatism
• Scar

rather than recurrent pain.

Slit-Lamp Findings

Early disease shows:

Bilateral central and paracentral subepithelial/anterior stromal opacities

that may become:

• Reticular
• Geographic
• Honeycomb-like

Honeycomb Appearance

A classic finding is:

Irregular gray-white honeycomb or reticular opacification of the anterior central cornea

These lesions primarily involve:

• Bowman layer
• Very anterior stroma

and tend to become more confluent with age.

Advanced Disease

Later findings include:

• Dense gray-white superficial opacity
• Irregular anterior corneal surface
• Loss of normal Bowman layer
• Superficial stromal fibrosis
• Irregular astigmatism

The old description of:

“Curdled milk”

may be encountered in historical literature but is not essential diagnostically.

Corneal Erosions

During an active erosion, examination may show:

• Epithelial defect
• Loose surrounding epithelium
• Fluorescein staining
• Mild stromal edema

The underlying dystrophy remains visible between episodes.

Visual Loss

Vision declines because of:

• Central superficial opacity
• Irregular astigmatism
• Corneal surface distortion
• Progressive fibrosis

Early disease may still have relatively good corrected acuity.

Diagnosis

Diagnosis is usually based on:

• Early age of onset
• Recurrent erosions
• Bilateral honeycomb anterior corneal opacities
• Family history
• Characteristic superficial location

Genetic testing can confirm:

TGFBI-related disease

and distinguish overlapping phenotypes.

Genetic Testing

Testing is particularly useful when:

• Phenotype overlaps with Thiel-Behnke dystrophy
• Family counseling is desired
• Surgical planning is being considered
• Diagnosis is uncertain

Identification of a:

TGFBI p.Arg124Leu variant

strongly supports classic RBCD.

Family Examination

Because inheritance is autosomal dominant:

First-degree relatives should be offered slit-lamp examination

when clinically appropriate.

Genetic counseling may be useful for affected families.

Anterior Segment OCT

AS-OCT may demonstrate:

• Hyperreflective subepithelial deposits
• Bowman layer disruption
• Depth of anterior stromal involvement

This is particularly useful before:

PTK

to estimate treatment depth.

In Vivo Confocal Microscopy

Confocal microscopy may show:

• Highly reflective extracellular material
• Abnormal basal epithelium
• Disturbed Bowman layer
• Superficial stromal deposits

It is usually supportive rather than necessary for diagnosis.

Corneal Topography / Tomography

Useful when evaluating:

• Irregular astigmatism
• Progressive visual decline
• Surgical planning

It may show increasingly irregular corneal optics as fibrosis advances.

Differential Diagnosis

Important differentials include:

• Thiel-Behnke corneal dystrophy
• Epithelial basement membrane dystrophy
• Granular corneal dystrophy
• Lattice corneal dystrophy
• Meesmann corneal dystrophy
• Salzmann nodular degeneration
• Superficial corneal scarring
• Herpes simplex keratitis

Reis-Bücklers vs Thiel-Behnke

These are the most important overlapping conditions.

Reis-Bücklers

• Usually earlier onset
• More severe recurrent erosions
• Honeycomb/geographic anterior opacity
• More rapid progression
• TGFBI p.Arg124Leu
• Rod-like deposits on EM

Thiel-Behnke

• Often somewhat later onset
• Honeycomb superficial opacity can look similar
• Usually slower progression
• TGFBI p.Arg555Gln
• Curly fibers on EM

Genetic testing is the most definitive modern distinction.

Reis-Bücklers vs EBMD

RBCD

• Childhood onset
• Autosomal dominant
• Progressive superficial scarring
• Honeycomb opacities
• Significant visual decline with age

EBMD

• Usually later onset
• Map-dot-fingerprint epithelial findings
• Often much milder
• Does not typically cause the characteristic dense Bowman/anterior stromal honeycomb scar pattern

Reis-Bücklers vs Granular Corneal Dystrophy

Granular dystrophy typically produces:

• Discrete white stromal deposits
• Relatively clear spaces between deposits initially

RBCD is much more:

• Superficial
• Diffuse
• Honeycomb-like

with prominent recurrent erosions early in life.

Reis-Bücklers vs Lattice Dystrophy

Lattice dystrophy typically demonstrates:

• Branching refractile stromal lines
• Amyloid deposition

rather than the superficial honeycomb pattern of RBCD.

Both can produce recurrent erosions.

Treatment Principles

Treatment has two goals:

1. Control recurrent epithelial erosions
2. Restore vision when superficial opacity and irregularity become significant

There is no therapy that corrects the underlying TGFBI mutation.

Treatment of Recurrent Erosions

Initial conservative therapy includes:

• Preservative-free artificial tears
• Lubricating ointment at bedtime
• Hypertonic sodium chloride ointment in selected cases

These reduce friction and epithelial trauma.

Acute Erosion

During a significant epithelial defect, treatment may include:

• Lubrication
• Short-term topical antibiotic prophylaxis
• Oral analgesics
• Cycloplegic when photophobia is significant

Bandage Contact Lens

A bandage contact lens can be used for:

• Large painful erosion
• Persistent epithelial defect
• Recurrent episodes despite lubrication

It provides:

• Mechanical protection
• Pain relief
• Epithelial stabilization

Close follow-up is required because of:

Microbial keratitis risk.

Topical Antibiotic

Antibiotic prophylaxis may be appropriate while:

• A significant epithelial defect is open
• A bandage contact lens is being used

It does not treat the dystrophy itself.

Topical Corticosteroids

Routine topical corticosteroid use solely to:

“Prevent corneal scarring”

during uncomplicated erosions is not standard modern treatment.

Steroids may:

• Delay epithelial healing
• Increase infection risk

They should be reserved for selected inflammatory indications under ophthalmic supervision.

Persistent/Recurrent Surface Disease

For recurrent erosions not controlled conservatively, options include:

• Epithelial debridement
• Superficial keratectomy
• Diamond-burr polishing in selected cases
• Phototherapeutic keratectomy

Because RBCD involves abnormal Bowman layer itself, definitive superficial treatment often needs to address more than loose epithelium alone.

Phototherapeutic Keratectomy

PTK is the preferred surgical treatment for visually significant superficial RBCD when disease depth is suitable.

Excimer laser ablation removes:

• Abnormal superficial tissue
• Fibrotic Bowman-layer material
• Irregular anterior stroma

This can:

• Improve visual acuity
• Regularize the surface
• Reduce recurrent erosions

PTK Indications

Consider PTK for:

• Visually significant superficial opacity
• Irregular astigmatism
• Frequent recurrent erosions
• Superficial scarring

especially when disease remains predominantly anterior.

PTK Advantages

Compared with corneal transplantation, PTK:

• Preserves native cornea
• Avoids intraocular surgery
• Has faster rehabilitation
• Can be repeated in selected cases

PTK Limitations

The main limitation is:

Recurrence

because genetically abnormal keratocytes and TGFBI protein production remain.

Deposits may recur over:

• Years
• Sometimes sooner

Refractive Effect of PTK

Because tissue is removed from the central cornea, PTK may produce:

Hyperopic shift

particularly with deeper ablation.

This should be considered during planning.

Mitomycin C With PTK

Mitomycin C has been used adjunctively in an attempt to reduce:

• Haze
• Recurrence

However:

Evidence that MMC reliably prevents recurrent TGFBI deposition is limited, and it is not a universally required component of PTK.

Use is individualized.

Superficial Keratectomy

When excimer PTK is unavailable, superficial keratectomy may remove:

• Abnormal epithelium
• Fibrotic superficial tissue

It can improve:

• Surface regularity
• Erosion frequency

but recurrence remains possible.

Keratoplasty

Corneal transplantation is reserved for:

• Deep or extensive anterior stromal scarring
• Severe visual loss not amenable to PTK
• Multiple failed superficial procedures

Options include:

• Anterior lamellar keratoplasty
• Deep anterior lamellar keratoplasty in selected cases
• Penetrating keratoplasty

Lamellar vs Penetrating Keratoplasty

Because disease is primarily anterior:

Lamellar approaches are attractive when the deeper stroma and endothelium are healthy.

Advantages include:

• Preservation of endothelium
• Lower rejection risk

PK may be necessary when opacity extends too deeply or lamellar surgery is unsuitable.

Recurrence After Keratoplasty

A major clinical feature of RBCD is:

Recurrence in the graft

because host-derived abnormal TGFBI protein can redeposit in transplanted tissue.

Recurrence may occur after:

• Lamellar keratoplasty
• Penetrating keratoplasty

Therefore transplantation is:

Not curative at the molecular level.

Postoperative Monitoring

After PTK or keratoplasty, monitor for:

• Epithelial healing
• Infection
• Haze
• Refractive change
• Recurrence of deposits
• Recurrent erosions

Pediatric Considerations

Children may have:

• Painful recurrent erosions
• Photophobia
• Eye rubbing
• Reduced visual function

Assess:

• Visual acuity
• Refraction
• Corneal clarity

Significant asymmetric visual loss can theoretically contribute to:

Amblyopia

and should be addressed during visual development.

Prevention

There is:

No known method to prevent development of RBCD

in a genetically affected individual.

General ocular surface protection includes:

• Avoiding unnecessary trauma
• Treating dry eye
• Using lubrication during recurrent erosion-prone periods

Prognosis

RBCD is:

Slowly progressive but recurrent

The natural history commonly includes:

• Painful erosions in childhood
• Increasing superficial opacity during adolescence
• Progressive visual impairment in adulthood

Visual Prognosis

Vision can often be substantially improved with:

• PTK
• Superficial keratectomy
• Keratoplasty in advanced cases

However:

Recurrence remains the central long-term problem.

Complications

Potential complications include:

• Recurrent corneal erosions
• Microbial keratitis
• Progressive superficial scarring
• Irregular astigmatism
• Reduced BCVA
• Recurrence after PTK
• Recurrence after corneal transplantation

Ophthalmology Pearls

• Reis-Bücklers corneal dystrophy is an autosomal dominant TGFBI-associated anterior corneal dystrophy with recurrent childhood erosions and progressive Bowman/anterior stromal scarring.
• The classic mutation is TGFBI p.Arg124Leu (R124L).
• The older gene name BIGH3 has been replaced by TGFBI.
• Symptoms typically begin during the first decade of life with recurrent painful epithelial erosions.
• Slit lamp shows bilateral central honeycomb/geographic gray-white opacities involving Bowman layer and superficial stroma.
• With age, pain from erosions may become less prominent while visual loss from superficial fibrosis and irregular astigmatism increases.
• The most important differential is Thiel-Behnke dystrophy, usually associated with TGFBI p.Arg555Gln.
• RBCD shows rod-like deposits ultrastructurally, whereas Thiel-Behnke shows characteristic curly fibers.
• Modern genetic testing often distinguishes the two more directly than electron microscopy.
• Conservative treatment of erosions includes preservative-free lubrication, nighttime ointment, and bandage contact lens when necessary.
• Routine topical corticosteroids solely to prevent scarring during epithelial erosions are not standard therapy.
• PTK is the principal surgical treatment for visually significant superficial disease, improving both surface regularity and recurrent erosions.
• PTK may produce a hyperopic shift, and recurrence is common because the underlying genetic defect persists.
• MMC has been used with PTK, but evidence that it prevents TGFBI redeposition is limited.
• Lamellar or penetrating keratoplasty is reserved for advanced scarring, but RBCD can recur in the graft.
• There are no known systemic associations; the disorder is primarily confined to the cornea.