Ophthalmology – Pseudoexfoliation Syndrome

Basics

Description

Pseudoexfoliation syndrome (PXS), also called exfoliation syndrome (XFS), is an age-related systemic extracellular matrix disorder characterized by production and deposition of abnormal fibrillar pseudoexfoliative material within the anterior segment.

Deposits occur on structures including:

• Anterior lens capsule
• Pupillary margin
• Iris
• Ciliary body
• Zonules
• Corneal endothelium
• Trabecular meshwork

Its two major ophthalmic consequences are:

• Secondary open-angle glaucoma
• Zonular weakness complicating cataract surgery

When glaucomatous optic neuropathy develops, the condition is termed:

Pseudoexfoliative glaucoma / exfoliation glaucoma (PXG/XFG)

Key Clinical Concept

The classic examination finding is:

Gray-white pseudoexfoliative material on the anterior lens capsule, especially after dilation

combined with:

• Poor pupillary dilation
• Peripupillary iris transillumination
• Dense angle pigmentation
• Sampaolesi line
• Zonular weakness

PXG is often:

More aggressive than primary open-angle glaucoma (POAG)

with:

• Higher IOP
• Greater IOP fluctuation
• Faster progression
• More frequent need for surgery

Pseudoexfoliation vs True Exfoliation

These are different disorders.

Pseudoexfoliation

• Abnormal fibrillar extracellular material
• Associated with glaucoma and zonulopathy
• Usually older adults

True Exfoliation

• Delamination of the anterior lens capsule
• Historically associated with intense infrared exposure, such as glassblowing
• Does not represent the same fibrillopathy

Epidemiology

PXS is strongly age-related and is uncommon before:

50–60 years

Prevalence varies substantially among:

• Geographic regions
• Ethnic groups
• Populations

High prevalence has historically been reported in:

• Scandinavian countries
• Northern Europe

but PXS occurs worldwide.

Laterality

PXS is frequently:

• Bilateral
• Markedly asymmetric

A patient may appear clinically unilateral for years.

The fellow eye may already have subclinical disease even when classic deposits are absent.

Risk Factors

Important associations include:

• Increasing age
• Family history
• Certain ethnic/geographic populations
• Genetic susceptibility

Female predominance is reported in some populations, but this is not universal.

Genetics

The strongest genetic association is with:

LOXL1

not “LOL1.”

LOXL1 encodes lysyl oxidase-like 1, which participates in:

• Elastin formation
• Extracellular matrix maintenance

LOXL1 Important Principle

LOXL1 risk variants are:

• Very common in the general population
• Present in many people who never develop PXS

Therefore:

LOXL1 testing has no routine clinical diagnostic or predictive role.

PXS is considered:

Multifactorial

with both genetic and environmental contributions.

Other Genetic Associations

Additional genes and pathways involving:

• Extracellular matrix regulation
• Oxidative stress
• Elastic fiber biology

have been implicated.

However, routine genetic testing is not currently indicated.

Pathophysiology

Pseudoexfoliative material is produced by several anterior segment tissues and deposited throughout the eye.

The abnormal material contains:

• Elastic microfibrillar components
• Glycoproteins
• Proteoglycans
• Basement membrane-related proteins

Altered extracellular matrix regulation and oxidative stress contribute to disease.

Glaucoma Mechanism

The principal glaucoma mechanism is:

Open-angle outflow obstruction

due to accumulation of:

• Pseudoexfoliative material
• Iris pigment
• Cellular debris

within the trabecular meshwork and juxtacanalicular tissue.

This produces:

• Increased outflow resistance
• Elevated IOP
• Large diurnal IOP fluctuations

Why Pigment Is Increased

Pigment liberation results from:

• Iris rubbing against the lens and zonules
• Degenerative iris changes
• Pupillary movement

This produces:

• Trabecular pigmentation
• Sampaolesi line
• Pupillary margin changes

Angle Closure

Although PXG is usually an:

Open-angle glaucoma

angle closure can also occur because of:

• Zonular weakness
• Anterior lens displacement
• Lens subluxation
• Pupillary block
• Progressive angle narrowing with age

Therefore:

Gonioscopy is essential.

Zonular Pathology

Pseudoexfoliative material accumulates on and around the zonules.

This leads to:

• Zonular fragility
• Phacodonesis
• Iridodonesis
• Lens subluxation
• Intraoperative zonular dialysis
• Late IOL–capsular bag dislocation

This is one of the most important practical consequences of PXS.

Corneal Changes

PXS may affect the corneal endothelium and is associated with:

• Reduced endothelial cell density
• Abnormal endothelial morphology
• Pigment deposition
• Increased risk of postoperative corneal edema

Severe endothelial compromise may occasionally cause:

• Corneal decompensation

Systemic Nature

Pseudoexfoliative material has been identified histologically in extraocular tissues.

Associations with:

• Cardiovascular disease
• Cerebrovascular disease
• Hearing impairment
• Vascular dysfunction

have been reported.

However:

The clinical significance of these systemic associations remains inconsistent, and routine systemic screening solely because of PXS is not established.

History

Most patients are:

Asymptomatic

until they develop:

• Glaucoma
• Cataract
• Lens instability

Ask about:

• Family history of glaucoma
• Previous high IOP
• Cataract surgery
• Trauma
• Fluctuating vision
• Progressive visual field loss

Slit-Lamp Examination

Typical findings include:

• Pseudoexfoliative material on anterior lens capsule
• Flakes at pupillary margin
• Poor pupillary dilation
• Loss of pupillary ruff
• Peripupillary transillumination
• Pigment on corneal endothelium
• Phacodonesis
• Iridodonesis

Classic Lens-Capsule Pattern

After dilation, the anterior lens capsule may show three zones:

1. Central gray-white disc
2. Intermediate clear zone
3. Peripheral granular ring of pseudoexfoliative material

The clear zone forms because the moving iris rubs material from the capsule.

This is a classic exam finding.

Pupillary Margin

Pseudoexfoliative material may accumulate as:

• White dandruff-like flakes

along the:

Pupillary ruff

Associated findings include:

• Loss of pupillary ruff
• Poor dilation
• Iris sphincter atrophy

Iris Transillumination

Typical defects are:

Peripupillary / pupillary-border transillumination defects

producing a moth-eaten appearance.

This helps distinguish PXS from pigment dispersion syndrome, where transillumination defects are usually:

Radial and midperipheral.

Poor Mydriasis

Poor dilation is common because of:

• Iris stromal degeneration
• Sphincter dysfunction
• Posterior synechiae in selected cases
• Mechanical changes associated with PXS

This is an important cataract-surgery risk factor.

Corneal Endothelium

Possible findings include:

• Scattered pseudoexfoliative deposits
• Pigment
• Endothelial changes

A Krukenberg spindle can occasionally occur but is much more characteristic of pigment dispersion.

Gonioscopy

Typical findings include:

• Open angle
• Increased trabecular pigmentation
• Often patchy or asymmetric pigmentation
• Sampaolesi line

Sampaolesi Line

A Sampaolesi line is pigment deposited anterior to:

Schwalbe line

It is commonly seen in:

• PXS
• Pigment dispersion

and is not pathognomonic.

Intraocular Pressure

IOP may be:

• Normal
• Intermittently elevated
• Persistently elevated

PXG often produces:

• Higher peak IOP
• Greater diurnal fluctuation
• More asymmetry between eyes

than POAG.

Pseudoexfoliation Syndrome vs Pseudoexfoliation Glaucoma

PXS

• Pseudoexfoliative material present
• No definite glaucomatous optic neuropathy required

PXG

• PXS findings
• Elevated IOP often present
• Glaucomatous optic nerve/RNFL damage
• Corresponding visual field loss

Optic Nerve Evaluation

Assess for:

• Neuroretinal rim thinning
• Focal notching
• RNFL defects
• Disc hemorrhage
• Increased cupping
• Inter-eye asymmetry

OCT

Obtain:

• Peripapillary RNFL
• Macular GCIPL/GCC
• Optic nerve head analysis

Progression analysis is valuable because PXG may progress rapidly.

Visual Fields

Automated perimetry may demonstrate:

• Nasal step
• Paracentral scotoma
• Arcuate defects
• Advanced field constriction

Because progression can be fast, field testing may need to be more frequent than in stable mild POAG.

Pachymetry

Measure central corneal thickness as part of glaucoma assessment.

CCT should influence:

• Risk interpretation
• Understanding of measured IOP

but should not be used with a simplistic numerical IOP “correction formula.”

Gonioscopy Before Dilation

Gonioscopy is useful before cataract surgery and glaucoma management to identify:

• Open vs narrow angle
• Degree of pigmentation
• PAS
• Lens-related angle crowding

Differential Diagnosis

Important differentials include:

• Pigment dispersion syndrome
• Primary open-angle glaucoma
• Chronic angle-closure glaucoma
• Uveitic glaucoma
• True exfoliation of lens capsule
• Pigment from previous trauma or surgery

PXS vs Pigment Dispersion Syndrome

PXS

Typically:

• Older patient
• Poor dilation
• Peripupillary transillumination
• Pseudoexfoliative material
• Zonular weakness
• Patchier angle pigment

Pigment Dispersion

Typically:

• Younger myope
• Deep anterior chamber
• Radial midperipheral transillumination
• Krukenberg spindle
• Dense homogeneous trabecular pigmentation
• No characteristic progressive zonulopathy

PXS vs POAG

POAG lacks:

• Pseudoexfoliative deposits
• Peripupillary transillumination pattern
• Zonular weakness
• Characteristic poor dilation

PXG often has:

Higher and more fluctuating IOP than typical POAG.

Treatment – PXS Without Glaucoma

If there is:

• Normal IOP
• Normal optic nerve
• Normal OCT
• Normal visual field

treatment is usually:

Observation

with periodic glaucoma surveillance.

Ocular Hypertension in PXS

PXS with elevated IOP carries a greater glaucoma risk than uncomplicated ocular hypertension.

Consider:

• Closer monitoring
• Lower threshold for treatment

depending on:

• IOP level
• Age
• Optic nerve
• CCT
• Family history
• Follow-up reliability

Treatment of PXG

Treatment aims to achieve a target IOP sufficient to prevent progression.

Because PXG may progress faster than POAG:

A relatively low target IOP may be necessary.

Medical Therapy

Common medications include:

• Prostaglandin analogs
• Beta-blockers
• Carbonic anhydrase inhibitors
• Alpha-2 agonists
• Rho-kinase inhibitors where available
• Fixed combinations

Prostaglandin Analogs

Prostaglandin analogs are commonly effective first-line therapy because of:

• Strong IOP reduction
• Once-daily dosing
• Good adherence profile

Selective Laser Trabeculoplasty

SLT is highly effective in many eyes with PXG.

Advantages include:

• Strong IOP response
• Avoidance of daily medications
• Suitability as primary or adjunctive treatment

SLT Considerations

The trabecular meshwork in PXS may be heavily pigmented.

Therefore:

• Start with appropriate/lower energy
• Titrate carefully
• Monitor for post-laser IOP spike

The initial response may be excellent but can diminish with time.

Important Modern Point

SLT is no longer merely a “second-line” treatment.

It may reasonably be used as:

First-line IOP-lowering therapy

in appropriate open-angle PXG.

Cataract Surgery

Cataract surgery in PXS requires special planning because of:

• Poor dilation
• Weak zonules
• Dense nucleus
• Increased risk of vitreous loss
• Increased postoperative inflammation

Preoperative Cataract Assessment

Look specifically for:

• Phacodonesis
• Iridodonesis
• Lens decentration
• Asymmetric anterior chamber depth
• Previous zonular dialysis
• Poor mydriasis
• Endothelial compromise

Intraoperative Risks

Possible complications include:

• Zonular dialysis
• Capsular rupture
• Vitreous loss
• Dropped lens material
• Capsular instability
• Iris trauma
• Corneal endothelial injury

Small-Pupil Management

Options include:

• Intracameral mydriatics
• Viscomydriasis
• Iris hooks
• Pupil expansion ring

Mechanical expansion should be used when necessary rather than forcing surgery through an inadequate pupil.

Zonular Support

Depending on zonular status, options include:

• Capsular tension ring (CTR)
• Capsular hooks
• Capsular tension segment
• Scleral fixation strategies

Capsular Tension Ring

A CTR can redistribute zonular forces in selected eyes with:

• Mild–moderate generalized zonular weakness

However:

A CTR does not guarantee long-term bag stability.

Late IOL–capsular bag complex dislocation can still occur.

Severe Zonular Weakness

With major zonular loss, more advanced support may be required, such as:

• Capsular tension segment
• Scleral-fixated capsular device
• Alternative IOL fixation

An experienced anterior segment surgeon is often appropriate.

Late IOL–Bag Complex Dislocation

One of the classic late complications of PXS is:

Delayed spontaneous dislocation of the entire IOL–capsular bag complex

often years after apparently uncomplicated cataract surgery.

This occurs because zonular degeneration continues after surgery.

Cataract Surgery Does Not Cure PXS

Removing the lens eliminates the classic lens-capsule deposits but:

Pseudoexfoliation is a systemic/anterior segment fibrillopathy and does not disappear after cataract extraction.

Glaucoma and zonular complications may still occur.

Glaucoma Surgery

If medications and SLT do not achieve target IOP, options include:

• Trabeculectomy
• Glaucoma drainage device
• Selected MIGS procedures
• Cyclophotocoagulation in refractory disease

Trabeculectomy

Trabeculectomy can achieve:

• Low target IOP

and remains important in:

• Advanced PXG
• Rapid progression
• Eyes requiring substantial pressure lowering

Glaucoma Drainage Devices

Tube shunts are useful when:

• Trabeculectomy is likely to fail
• Prior filtering surgery has failed
• Conjunctival/scarring factors favor a tube

MIGS

MIGS may be considered in:

• Mild to moderate PXG
• Particularly when combined with cataract surgery

However, for advanced disease requiring very low IOP:

MIGS may be insufficient.

Cyclophotocoagulation

Cyclodestructive procedures may be considered in:

• Refractory glaucoma
• Eyes with poor visual potential
• Selected seeing eyes using modern controlled techniques

Routine Laboratory Testing

Routine laboratory evaluation for:

• Homocysteine
• Vitamin levels

is not recommended solely because PXS is present.

Historical reports of hyperhomocysteinemia have not established a role for routine screening or supplementation.

Systemic Screening

There is currently no standard recommendation for routine:

• Cardiac imaging
• Vascular screening
• Hearing testing

solely because of PXS.

Systemic evaluation should be based on ordinary clinical indications.

Follow-Up – PXS Without Glaucoma

Patients with PXS but no glaucoma generally require:

At least annual ophthalmic follow-up

with:

• IOP
• Optic nerve evaluation
• Gonioscopy when appropriate
• OCT/visual fields according to risk

Closer follow-up is appropriate if:

• IOP is elevated
• Disease is markedly asymmetric
• Optic nerve is suspicious

Follow-Up – PXG

PXG should be monitored according to severity.

Visits may range from approximately:

• Every few months in active/advanced disease
• Less frequently when mild and stable

Monitor:

• IOP
• Optic nerve
• OCT
• Visual fields
• Treatment adherence
• Cataract/lens stability

Prognosis

PXS without glaucoma may remain stable for many years.

Once glaucoma develops:

PXG often behaves more aggressively than POAG.

Poor prognostic features include:

• Very high IOP
• Marked IOP fluctuation
• Advanced damage at diagnosis
• Poor follow-up
• Inadequate treatment

Complications

Important complications include:

• Pseudoexfoliative glaucoma
• Rapid glaucomatous field loss
• Poor pupillary dilation
• Zonular weakness
• Lens subluxation
• Cataract-surgery complications
• Late IOL–bag dislocation
• Corneal endothelial decompensation
• Chronic angle closure in selected eyes

Ophthalmology Pearls

• Pseudoexfoliation syndrome is an age-related fibrillopathy with abnormal extracellular material deposited on the lens, iris, zonules, corneal endothelium, and trabecular meshwork.
• The classic anterior lens appearance is central plaque + clear intermediate zone + peripheral granular ring after dilation.
• Look for poor dilation, peripupillary transillumination defects, loss of pupillary ruff, dense angle pigmentation, and Sampaolesi line.
• LOXL1 is the strongest genetic association, but routine genetic testing is not clinically useful.
• PXS is often bilateral but strikingly asymmetric.
• The major complications are glaucoma and zonular weakness.
• PXG is usually an open-angle glaucoma with higher IOP, greater fluctuation, and faster progression than typical POAG.
• SLT can be an effective first-line or adjunctive therapy, but use cautious energy in heavily pigmented angles because of post-laser IOP spikes.
• Cataract surgery is more difficult because of small pupil and weak zonules.
• A CTR can support the capsular bag but does not eliminate the risk of late IOL–bag complex dislocation.
• Cataract extraction does not cure pseudoexfoliation; glaucoma and zonular degeneration may continue afterward.
• Peripupillary transillumination favors PXS, whereas radial midperipheral transillumination favors pigment dispersion syndrome.
• Routine homocysteine testing or vitamin supplementation is not recommended solely because of PXS.
• Patients with PXS require long-term surveillance because conversion from apparently uncomplicated PXS to ocular hypertension or glaucoma can occur over time.

Ophthalmology – Primary Optic Nerve Sheath Meningioma

Basics

Description

Optic nerve sheath meningioma (ONSM) is a usually benign, slow-growing meningioma arising from the arachnoid cap cells of the meninges surrounding the optic nerve.

It produces a chronic compressive optic neuropathy through:

• Direct compression of the optic nerve
• Compromise of the pial vascular supply
• Compression of the central retinal venous circulation

The classic clinical pattern is:

Slowly progressive, painless, unilateral visual loss in a middle-aged adult

with characteristic enhancement around the optic nerve on orbital imaging.

Primary vs Secondary ONSM

Primary ONSM

Arises directly from the:

• Intraorbital optic nerve sheath
• Optic canalicular sheath

This is the classic form.

Secondary Optic Nerve Sheath Involvement

A meningioma arising elsewhere, particularly:

• Planum sphenoidale
• Tuberculum sellae
• Sphenoid wing

may secondarily extend along or compress the optic nerve.

These lesions have a different surgical and neuro-ophthalmic context.

Epidemiology

ONSM is uncommon.

It accounts for approximately:

• 1–2% of meningiomas
• A small proportion of orbital tumors

Most cases are:

• Unilateral
• Sporadic

Typical age at diagnosis:

Middle adulthood

with a female predominance.

Pediatric ONSM

ONSM is uncommon in children.

When diagnosed in a child or young adult, consider:

NF2-related schwannomatosis

formerly called neurofibromatosis type 2.

Pediatric ONSM may be:

• Bilateral
• Multifocal
• More strongly associated with an underlying tumor-predisposition syndrome

Genetics

Most sporadic ONSMs are not inherited.

Meningiomas frequently show alterations involving:

Chromosome 22 and the NF2 gene

When associated with NF2-related schwannomatosis, inheritance is:

Autosomal dominant

although de novo variants are common.

Pathophysiology

The tumor grows circumferentially around the optic nerve within its meningeal sheath.

Visual loss results from:

• Chronic axonal compression
• Ischemia of the optic nerve
• Disturbance of pial circulation
• Secondary venous outflow obstruction

Because the tumor often encases rather than directly invades the optic nerve, modern radiotherapy can control growth while preserving useful vision in many patients.

Clinical Presentation

The most common symptom is:

Slowly progressive painless visual loss

usually occurring over:

• Months
• Years

Other symptoms may include:

• Dyschromatopsia
• Visual field loss
• Relative afferent pupillary defect
• Proptosis
• Diplopia
• Transient visual obscurations

Visual Acuity

Visual acuity may range from:

• Normal or near-normal early
• Mildly reduced
• Profoundly reduced in advanced disease

Visual field and color vision abnormalities may precede major acuity loss.

Color Vision

Color vision is frequently reduced early because of:

Optic nerve dysfunction

and may be disproportionately impaired relative to Snellen acuity.

Relative Afferent Pupillary Defect

A RAPD is expected when disease is:

• Unilateral
• Markedly asymmetric

unless optic nerve function is profoundly reduced bilaterally.

Visual Field Defects

Possible field defects include:

• Central scotoma
• Cecocentral scotoma
• Arcuate defects
• Altitudinal defects
• Peripheral constriction

There is no single pathognomonic field pattern.

Serial perimetry is particularly useful for:

Monitoring progression.

Optic Disc Appearance

The optic disc may be:

• Normal
• Edematous
• Pale
• Atrophic

depending on:

• Tumor location
• Duration
• Degree of axonal damage

Optic Disc Edema

More anterior tumors may cause:

• Disc edema
• Venous congestion

because compression occurs closer to the globe.

Optic Atrophy

Posterior or chronic lesions more often produce:

Optic disc pallor

with corresponding:

• RNFL thinning
• Ganglion cell loss

Optociliary Shunt Vessels

A classic finding is:

Optociliary shunt vessels

These are collateral vessels on the optic disc connecting:

• Retinal venous circulation
• Choroidal circulation

They develop because chronic optic nerve sheath compression impairs normal venous drainage.

Classic Triad

The historical triad is:

1. Progressive visual loss
2. Optic atrophy
3. Optociliary shunt vessels

This combination is highly suggestive of ONSM but:

Not pathognomonic.

Proptosis

Proptosis may occur when the tumor becomes sufficiently large within the orbit.

It is typically:

• Axial
• Slowly progressive

because the optic nerve occupies the intraconal space.

Ocular Motility

Diplopia or motility restriction may occur because of:

• Mass effect
• Mechanical displacement
• Advanced orbital involvement

but is usually not an early feature.

Diagnosis

Diagnosis is usually based on:

• Characteristic neuro-ophthalmic findings
• High-quality orbital MRI

Biopsy is generally unnecessary.

MRI – Investigation of Choice

The preferred imaging study is:

MRI of the brain and orbits with and without contrast

using:

• Thin orbital sections
• Fat-suppressed postcontrast T1 imaging
• Axial and coronal views

Characteristic MRI Findings

Typical findings include:

• Tubular enlargement around optic nerve
• Fusiform sheath enlargement
• Intense enhancement of the tumor
• Relative nonenhancement of the central optic nerve

This produces the classic:

Tram-track sign

on axial imaging.

Doughnut Sign

On coronal imaging, enhancing tumor surrounding the relatively less enhancing optic nerve may produce a:

Doughnut sign

or ring-like appearance.

Imaging Morphology

ONSM may appear:

• Tubular
• Fusiform
• Globular
• Focal

Tumor may extend through:

• Optic canal
• Orbital apex

and occasionally intracranially.

CT

Thin-section CT is particularly useful for detecting:

• Calcification
• Optic canal enlargement
• Hyperostosis

Calcification strongly supports a meningioma in the appropriate clinical setting.

MRI remains superior for:

• Soft tissue
• Optic nerve
• Intracranial extension

OCT

OCT is increasingly valuable for monitoring ONSM.

Assess:

• Peripapillary RNFL
• Macular ganglion cell complex / GCIPL

Progressive thinning reflects:

Axonal loss

and may help quantify chronic optic neuropathy.

Important OCT Principle

Severe preexisting:

• RNFL thinning
• GCIPL loss

suggests limited potential for visual recovery even if the tumor is successfully controlled.

Radiotherapy primarily aims to:

Preserve remaining function

rather than regenerate lost axons.

Visual Fields

Formal automated perimetry should be performed serially when vision permits.

It is useful for:

• Baseline documentation
• Detecting progression
• Assessing response after treatment

Biopsy

Biopsy is:

Rarely indicated

because characteristic MRI findings are usually sufficient and surgery around the optic nerve carries substantial visual risk.

When Biopsy May Be Considered

Biopsy may be considered when:

• Imaging is atypical
• Rapid progression suggests another disease
• Malignancy is suspected
• Inflammatory/infiltrative disease cannot be excluded

Even then, biopsy should be approached cautiously.

Why Biopsy Is Avoided

The optic nerve blood supply is intimately associated with:

• Meningeal vessels
• Pial vessels
• Tumor sheath

Surgical manipulation can cause:

• Ischemia
• Direct optic nerve injury

with permanent loss of vision.

Differential Diagnosis

Important differentials include:

• Optic pathway glioma
• Optic perineuritis
• Sarcoidosis
• Lymphoma
• Metastatic disease
• IgG4-related orbital disease
• Idiopathic orbital inflammation
• Optic neuritis
• Leukemic infiltration
• Other orbital tumors

ONSM vs Optic Nerve Glioma

ONSM

Typically:

• Middle-aged adult
• Female predominance
• Sheath enhancement around nerve
• Tram-track appearance
• Calcification possible
• Optociliary shunt vessels possible

Optic Pathway Glioma

Typically:

• Childhood
• NF1 association
• Fusiform enlargement of the optic nerve itself
• Less characteristic sheath-type enhancement

ONSM vs Optic Perineuritis

Optic perineuritis may also produce:

• Perineural enhancement
• Tram-track appearance

but usually has a different clinical setting.

Features favoring perineuritis include:

• More acute/subacute symptoms
• Orbital pain
• Inflammatory disease
• Steroid responsiveness

ONSM usually causes:

Slow, painless progression.

ONSM vs Optic Neuritis

Typical optic neuritis usually causes:

• Acute/subacute visual loss
• Pain with eye movement
• Dyschromatopsia
• Often younger age
• Intraneural rather than sheath-predominant enhancement

ONSM generally progresses much more slowly.

ONSM vs Sarcoidosis

Sarcoidosis may produce:

• Optic nerve sheath enhancement
• Optic neuropathy
• Orbital inflammation

Look for:

• Uveitis
• Lacrimal gland enlargement
• Systemic pulmonary findings
• Other inflammatory manifestations

Natural History

ONSM is usually:

Slow-growing

but progressive visual loss may occur even when tumor size changes little.

This reflects:

• Optic nerve compression
• Ischemic injury

rather than simply tumor volume.

Observation

Observation may be appropriate when:

• Vision is good
• Visual fields are stable
• Tumor is radiographically stable
• Patient is minimally symptomatic

This is especially reasonable in:

• Older patients
• Patients with significant medical comorbidity

Monitoring During Observation

Follow with:

• Visual acuity
• Color vision
• Pupils
• Visual fields
• OCT RNFL/GCIPL
• MRI

Initially, review may be every:

3–6 months

depending on disease severity.

MRI may be repeated approximately:

Every 6–12 months initially

then less frequently if stable.

Indications for Treatment

Treatment is considered when there is:

• Documented progressive visual loss
• Progressive visual field loss
• Tumor growth
• Significant visual impairment at presentation with salvageable vision
• Intracranial progression threatening the chiasm or fellow optic nerve

First-Line Definitive Treatment

For a patient with useful vision and progressive ONSM, the preferred treatment is:

Fractionated conformal radiotherapy

including modern:

• Fractionated stereotactic radiotherapy
• Intensity-modulated radiotherapy
• Proton therapy in selected centers

Why Fractionation Is Preferred

The optic nerve is highly sensitive to radiation injury.

Fractionating the total dose allows:

• Tumor control
• Better preservation of surrounding neural tissue
• Lower risk of radiation optic neuropathy than high single-dose treatment

Typical Radiation Dose

Common modern regimens use approximately:

50–54 Gy

delivered in fractions of roughly:

1.8 Gy

The exact regimen is determined by:

• Tumor geometry
• Prior radiation
• Optic nerve/chiasm constraints
• Radiation oncology planning

Treatment Outcomes

Fractionated radiotherapy achieves:

• Tumor control in >90% of cases
• Stabilization or improvement of vision in a large majority of appropriately selected patients

Visual recovery is more likely when treatment occurs before:

• Severe optic atrophy
• Profound RNFL loss
• Long-standing blindness

Time Course After Radiotherapy

Tumor size may not dramatically decrease.

Successful treatment is often reflected by:

• Stabilization of vision
• Improved visual field
• Reduced tumor growth
• Long-term radiographic stability

Therefore:

Clinical function is as important as tumor size.

Stereotactic Radiosurgery

Single-fraction stereotactic radiosurgery is generally less favored for tumors immediately surrounding a functional optic nerve because:

High single-dose radiation increases the risk of radiation optic neuropathy.

Fractionated techniques are usually preferred.

Surgery

Surgical excision of a primary ONSM is usually:

Avoided when useful vision remains.

Because the tumor surrounds and shares blood supply with the optic nerve, complete removal often results in:

Blindness in the operated eye.

Surgical Indications

Surgery may be considered when:

• Eye is already blind
• Tumor produces disfiguring or painful proptosis
• There is aggressive intracranial extension
• Diagnosis remains uncertain and tissue is essential

Even then, management should be individualized.

Intracranial Extension

Tumor extending toward:

• Optic canal
• Chiasm
• Contralateral optic nerve

requires multidisciplinary management involving:

• Neuro-ophthalmology
• Neurosurgery
• Radiation oncology

The priority is preventing:

Contralateral visual loss

and intracranial progression.

Pediatric Management

Treatment in children requires particular caution because of:

• Long life expectancy
• Radiation-related secondary tumor risk
• Endocrine and neurocognitive effects of cranial irradiation

Association with NF2-related schwannomatosis should be investigated in appropriate cases.

Radiation Complications

Possible complications include:

• Radiation optic neuropathy
• Radiation retinopathy
• Retinal vascular occlusion
• Cataract
• Dry eye
• Pituitary dysfunction depending on radiation field
• Secondary neoplasm, particularly relevant in younger patients

With modern fractionated techniques, severe complications are uncommon but not absent.

Radiation Retinopathy

Radiation retinopathy may develop:

• Months to years after treatment

Findings may include:

• Microaneurysms
• Hemorrhages
• Cotton-wool spots
• Macular edema
• Neovascularization

Treatment may include:

Intravitreal anti-VEGF

when macular edema or proliferative changes develop.

Radiation Optic Neuropathy

Radiation optic neuropathy causes:

• Sudden or subacute visual loss
• RAPD
• Optic disc edema or later pallor

Prevention through:

Appropriate radiation dose constraints

is critical because established injury can be severe and difficult to reverse.

Follow-Up After Treatment

Continue long-term monitoring with:

• Visual acuity
• Color vision
• Visual fields
• OCT RNFL/GCIPL
• MRI

Follow-up is required for years because:

• Tumor recurrence/progression can occur
• Radiation complications may be delayed

Prognosis

ONSM is histologically benign but can be:

Functionally devastating

because progressive compression may ultimately destroy the optic nerve.

Untreated progressive disease can lead to:

• Severe visual field loss
• Optic atrophy
• Blindness

Visual Prognosis

The best predictors of useful visual outcome include:

• Better vision at treatment
• Less severe optic atrophy
• Preserved RNFL/GCC
• Shorter duration of progressive visual loss

Once profound optic atrophy is established:

Visual recovery is unlikely.

Tumor Prognosis

Local tumor control after modern fractionated radiotherapy is:

Excellent

in most patients.

The main therapeutic goal is therefore:

Preservation of useful vision rather than eradication of a benign tumor at the cost of optic nerve function.

Complications

Potential complications of untreated ONSM include:

• Progressive compressive optic neuropathy
• Optic atrophy
• Severe visual field loss
• Blindness
• Proptosis
• Intracranial extension

Treatment complications include:

• Radiation retinopathy
• Radiation optic neuropathy
• Cataract
• Surgical blindness

Ophthalmology Pearls

• Optic nerve sheath meningioma is a usually benign tumor arising from arachnoid cap cells surrounding the optic nerve and causing chronic compressive optic neuropathy.
• The classic patient is a middle-aged woman with slowly progressive, painless, unilateral visual loss.
• The classic triad is progressive visual loss + optic atrophy + optociliary shunt vessels, although the full triad is not always present.
• MRI of the orbits with fat-suppressed postcontrast imaging is the diagnostic study of choice.
• The characteristic axial imaging appearance is the tram-track sign; coronal imaging may show a doughnut sign.
• CT is useful for demonstrating calcification and hyperostosis.
• OCT RNFL and GCIPL help quantify optic nerve damage and monitor progression.
• Biopsy is rarely required and may sacrifice vision, so characteristic radiographic cases are generally diagnosed noninvasively.
• Important mimics include optic glioma and optic perineuritis.
• Observation is appropriate when vision and imaging are stable.
• Progressive visual dysfunction with useful remaining vision is best treated with fractionated radiotherapy, typically around 50–54 Gy in conventional small fractions.
• Modern fractionated radiotherapy provides excellent local control and stabilizes or improves vision in most appropriately selected patients.
• Single-fraction radiosurgery is generally avoided near a functioning optic nerve because of the risk of radiation optic neuropathy.
• Surgical resection is usually avoided when useful vision remains, because removing the sheath tumor commonly damages or devascularizes the optic nerve.
• ONSM in children or young adults should raise consideration of NF2-related schwannomatosis.
• The key therapeutic principle is preserve remaining optic nerve function rather than aggressively excise a histologically benign tumor.

Ophthalmology – Presumed Ocular Histoplasmosis Syndrome

Basics

Description

Presumed ocular histoplasmosis syndrome (POHS) is a characteristic chorioretinal syndrome associated epidemiologically with prior exposure to Histoplasma capsulatum.

It is defined clinically by the classic combination of:

• Multiple punched-out chorioretinal scars (“histo spots”)
• Peripapillary chorioretinal atrophy
• Absence of anterior chamber inflammation and vitritis

The major sight-threatening complication is:

Macular neovascularization (MNV/CNV)

which may produce hemorrhage, exudation, subretinal fluid, fibrosis, and permanent central visual loss.

Important Modern Concept

The association between POHS and Histoplasma capsulatum is strong epidemiologically but remains:

Presumed rather than microbiologically proven in most affected eyes.

Classic POHS is not considered an active fungal infection of the eye.

Therefore:

• Antifungal therapy is not indicated for typical POHS
• Corticosteroids are not routine treatment
• Management is directed primarily toward MNV detection and treatment

Epidemiology

POHS is most strongly associated with areas where H. capsulatum is endemic, particularly in the United States:

• Ohio River Valley
• Mississippi River Valley
• Parts of the central and eastern United States

Many people in endemic regions have been exposed to Histoplasma without developing POHS.

Only a small proportion develop the characteristic ocular phenotype.

Histoplasma Exposure

Histoplasma capsulatum is a dimorphic fungus found particularly in soil contaminated by:

• Bird droppings
• Bat droppings

Exposure may occur around:

• Caves
• Chicken coops
• Old buildings
• Demolition sites
• Excavation
• Soil disruption

Most infections are:

• Asymptomatic
• Mild respiratory infections

The ocular syndrome may become clinically apparent long after the presumed systemic exposure.

Pathogenesis

The precise mechanism remains uncertain.

A proposed sequence is:

Prior systemic Histoplasma exposure → hematogenous seeding or immune-mediated choroidal injury → healed focal chorioretinal scars → later MNV in susceptible lesions

However, viable fungal organisms are generally not demonstrable in classic POHS lesions.

Thus the current concept favors:

• Prior infectious trigger
• Subsequent inflammatory/chorioretinal scarring
• Late neovascular complications

rather than chronic active fungal infection.

Genetics

Certain HLA associations have historically been reported, suggesting that:

Host immune susceptibility may influence the development of POHS

after Histoplasma exposure.

Routine genetic testing has no clinical role.

Clinical Presentation

Patients may be:

Completely asymptomatic

if lesions are peripheral or inactive.

Symptoms usually arise when MNV develops near the macula.

These may include:

• Metamorphopsia
• Central blur
• Paracentral scotoma
• Micropsia
• Reduced central vision

Laterality

POHS may be:

• Unilateral clinically
• Bilateral

Even when symptoms occur in only one eye, the fellow eye may show:

• Histo spots
• Peripapillary atrophy

Classic Fundus Triad

The classic triad is:

1. Punched-out chorioretinal scars
2. Peripapillary atrophy
3. No vitritis

The absence of vitreous inflammation is particularly important diagnostically.

Histo Spots

Histo spots are small, discrete, round or oval areas of:

• Chorioretinal atrophy
• RPE disturbance

They are commonly:

• Yellow-white when relatively fresh
• Pigmented or atrophic when healed

They may occur in:

• Macula
• Midperiphery
• Peripheral retina

Macular Histo Spots

Macular histo spots are clinically important because they increase the risk of:

Secondary MNV

which is the major cause of severe visual loss in POHS.

Peripapillary Atrophy

Typical peripapillary findings include:

• Circumferential or irregular chorioretinal atrophy
• Pigmentary alteration adjacent to the optic nerve

This may be subtle or extensive.

Histo Streaks

Linear chorioretinal scars may occasionally be seen and have historically been called:

Histo streaks

These are less diagnostically important than the classic triad.

Absence of Inflammation

Classic POHS lacks:

• Anterior chamber cells
• Vitreous cells
• Vitreous haze

This feature helps distinguish it from inflammatory disorders such as:

Multifocal choroiditis with panuveitis

Macular Neovascularization

MNV may develop adjacent to:

• Macular histo spots
• Peripapillary scars

Typical manifestations include:

• Gray-green subretinal lesion
• Subretinal hemorrhage
• Intraretinal or subretinal fluid
• Lipid exudation
• Pigment epithelial detachment
• Fibrosis

Peripapillary MNV

POHS may also produce:

Peripapillary MNV

which can enlarge toward:

• Papillomacular bundle
• Fovea

and become visually significant.

Disciform Scar

Untreated or chronic MNV may evolve into:

• Fibrovascular scar
• Disciform macular scar

causing permanent central vision loss.

Diagnosis

POHS is a:

Clinical diagnosis

There is no laboratory test that confirms classic ocular disease.

Diagnosis rests on:

• Characteristic fundus findings
• Lack of vitreous inflammation
• Compatible epidemiologic history
• Imaging when MNV is suspected

Laboratory Testing

Routine testing for:

• Histoplasma antibodies
• Serum antigen
• Urine antigen

is generally:

Not useful for isolated POHS

because these tests are designed primarily for diagnosing active systemic histoplasmosis.

Histoplasmin Skin Testing

Histoplasmin skin testing is:

Obsolete for routine ophthalmic diagnosis

and should not be used to establish POHS.

Fundus Photography

Fundus photography is useful for documenting:

• Histo spots
• Peripapillary atrophy
• Hemorrhage
• Pigmentary change
• Scar progression

Optical Coherence Tomography

OCT is the key modern structural test when MNV is suspected.

It may demonstrate:

• Subretinal hyperreflective material
• Subretinal fluid
• Intraretinal fluid
• RPE elevation
• Fibrosis
• Outer retinal atrophy

OCT is also useful for monitoring response to anti-VEGF therapy.

OCT Angiography

OCTA can demonstrate a neovascular network without intravenous dye.

It is useful for:

• Detecting MNV
• Monitoring vascular activity
• Assessing lesions when fluorescein angiography is undesirable

However, OCTA should be interpreted alongside:

• Structural OCT
• Clinical examination

because visible flow does not always indicate active exudation.

Fluorescein Angiography

FA may show:

• Early hyperfluorescence of classic MNV
• Progressive leakage in active lesions
• Window defects corresponding to atrophic histo spots

It remains useful when:

• Diagnosis is uncertain
• Lesion activity needs clarification

Indocyanine Green Angiography

ICG is rarely required for routine POHS.

It may be useful when:

• Choroidal pathology is atypical
• Differential diagnosis remains uncertain

Differential Diagnosis

Important differentials include:

• Multifocal choroiditis with panuveitis
• Punctate inner choroidopathy
• Pathologic myopia
• Age-related macular degeneration
• Angioid streaks
• Idiopathic MNV
• Other causes of multifocal chorioretinal scars
• Ocular toxoplasmosis
• Ocular tuberculosis
• Syphilitic chorioretinitis
• Active fungal chorioretinitis

POHS vs Multifocal Choroiditis

This distinction is particularly important.

POHS

Typically:

• Punched-out scars
• Peripapillary atrophy
• No vitritis
• MNV may occur

Multifocal Choroiditis with Panuveitis

Typically:

• Similar punched-out lesions
• Vitritis present
• May have anterior chamber inflammation
• Often inflammatory symptoms
• MNV may also occur

The presence of intraocular inflammation argues strongly against classic POHS.

POHS vs Punctate Inner Choroidopathy

PIC usually occurs in:

• Young myopic women

and produces:

• Small yellow-white posterior pole lesions
• Little or no vitritis
• High risk of MNV

Unlike POHS, PIC generally lacks the classic combination of:

• Widespread histo spots
• Peripapillary atrophy
• Endemic Histoplasma association

POHS vs Pathologic Myopia

Myopic MNV occurs in eyes with:

• High axial myopia
• Tessellated fundus
• Lacquer cracks
• Posterior staphyloma
• Myopic macular degeneration

These structural findings distinguish it from typical POHS.

POHS vs AMD

AMD generally occurs in older adults and is associated with:

• Drusen
• Pigment epithelial abnormalities
• Geographic atrophy

POHS typically lacks:

Drusen as the central disease feature

and occurs in a younger population.

Active Histoplasma Chorioretinitis

An important distinction:

Classic POHS is not the same as active ocular histoplasmosis in an immunocompromised patient.

Disseminated histoplasmosis can occasionally produce:

• Active chorioretinitis
• Systemic illness
• Multiorgan infection

especially in:

• Advanced HIV
• Transplant recipients
• Other severely immunosuppressed patients

These patients require systemic infectious-disease evaluation and antifungal therapy.

Treatment

Inactive POHS Without MNV

No treatment is required for:

• Inactive histo spots
• Stable peripapillary atrophy
• Asymptomatic scars

Management consists of:

• Observation
• Patient education
• Surveillance for MNV

Antifungal Therapy

Antifungal treatment is not indicated for classic POHS.

The ocular syndrome does not represent proven active fungal replication.

Antifungal therapy is reserved for:

Active systemic or ocular histoplasmosis, not presumed ocular histoplasmosis syndrome.

Corticosteroids

Routine corticosteroid treatment is:

Not recommended for typical POHS

because the classic syndrome lacks active intraocular inflammation.

If active inflammatory choroiditis is present, reconsider whether the diagnosis is actually:

• Multifocal choroiditis
• PIC
• Infectious choroiditis
• Another inflammatory disorder

rather than classic POHS.

Treatment of MNV

The modern first-line treatment for POHS-associated MNV is:

Intravitreal anti-VEGF therapy

Anti-VEGF Therapy

Agents used include:

• Bevacizumab
• Ranibizumab
• Aflibercept
• Other approved anti-VEGF agents depending on region and availability

Treatment usually produces:

• Reduction in fluid
• Reduction in hemorrhage
• Stabilization or improvement of visual acuity

Treatment Strategy

Treatment is individualized using:

• OCT evidence of activity
• Visual acuity
• Hemorrhage
• Symptoms

Many patients require:

• Several initial injections
• Followed by PRN or treat-and-extend style monitoring

The exact strategy depends on lesion behavior.

Anti-VEGF Prognosis

POHS-associated MNV often responds:

Very well to anti-VEGF therapy

particularly when detected early before:

• Foveal fibrosis
• Extensive atrophy

Thermal Laser

Thermal laser photocoagulation was historically used for:

• Extrafoveal MNV

but it is now rarely used because:

Anti-VEGF therapy provides superior anatomic flexibility and avoids immediate laser scotoma.

Photodynamic Therapy

Verteporfin PDT was also used historically.

It has largely been superseded by:

Anti-VEGF therapy

but may occasionally have a role in unusual refractory cases.

Submacular Surgery

Surgical removal of MNV was historically attempted.

It is now:

Obsolete for routine POHS-associated MNV

because anti-VEGF therapy provides better risk-benefit balance.

Follow-Up

Patients with inactive POHS should have periodic examination.

Frequency depends on:

• Presence of macular scars
• Fellow-eye history of MNV
• Symptoms
• Age
• Other macular disease

Annual follow-up is reasonable for many stable patients.

Higher-Risk Follow-Up

More frequent review is appropriate when there is:

• Previous MNV
• Macular histo spot
• Recent new symptoms
• Suspicious OCT changes
• Fellow-eye neovascular disease

Home Monitoring

Patients should monitor central vision using:

• Amsler grid
• Preferably monocularly

They should report immediately:

• New distortion
• Wavy lines
• Central blur
• Missing areas
• New scotoma

Prognosis

Patients without MNV usually maintain:

Excellent vision

because peripheral histo spots are often visually insignificant.

Visual prognosis depends primarily on:

• Development of MNV
• Location relative to fovea
• Speed of diagnosis
• Response to anti-VEGF
• Degree of residual fibrosis or atrophy

Fellow-Eye Risk

Patients who develop MNV in one eye are at increased risk of:

• MNV in the fellow eye

especially if the fellow eye contains:

• Macular histo spots

Long-term bilateral surveillance is therefore important.

Complications

The principal complication is:

Macular neovascularization

which can cause:

• Subretinal hemorrhage
• Exudation
• Fibrosis
• Disciform scar
• Permanent central visual loss

Other POHS lesions usually remain stable.

Ophthalmology Pearls

• POHS is diagnosed clinically by punched-out chorioretinal scars, peripapillary atrophy, and absence of vitritis.
• The classic lesions are called histo spots.
• POHS is strongly associated epidemiologically with prior Histoplasma capsulatum exposure, especially in the Ohio and Mississippi River valleys, but direct fungal causation within the eye is usually unproven.
• No vitreous inflammation is a key diagnostic feature; vitritis should make you reconsider multifocal choroiditis or another inflammatory/infectious process.
• Most patients are asymptomatic until macular neovascularization develops.
• MNV is the major cause of vision loss in POHS.
• Macular histo spots increase the risk of subsequent MNV.
• Routine Histoplasma serology, urine antigen, and skin testing are not useful for diagnosing classic POHS.
• OCT is central for detecting and monitoring MNV; OCTA and FA are useful adjuncts.
• Intravitreal anti-VEGF therapy is first-line treatment for POHS-associated MNV.
• Thermal laser, PDT, and submacular surgery are largely historical treatments in the anti-VEGF era.
• Antifungal therapy is not indicated for classic POHS, because it is not considered active ocular fungal infection.
• Classic POHS should be distinguished from disseminated histoplasmosis with active chorioretinitis in immunocompromised patients, which requires systemic antifungal treatment.
• Stable POHS without MNV requires observation, periodic follow-up, and home central-vision monitoring.
• New metamorphopsia or central blur should prompt urgent OCT evaluation for MNV.

Important Modern Concept The association between POHS and Histoplasma capsulatum is strong epidemiologically but remains: Presumed rather than microbiologically proven in most affected eyes. Classic POHS is not considered an active fungal infection of the eye. Therefore:  Antifungal therapy is not indicated for typical POHS Corticosteroids are not routine treatment Management is directed primarily toward MNV detection and treatment

Epidemiology POHS is most strongly associated with areas where H. capsulatum is endemic, particularly in the United States:  Ohio River Valley Mississippi River Valley Parts of the central and eastern United States  Many people in endemic regions have been exposed to Histoplasma without developing POHS. Only a small proportion develop the characteristic ocular phenotype.

Histoplasma Exposure Histoplasma capsulatum is a dimorphic fungus found particularly in soil contaminated by:  Bird droppings Bat droppings  Exposure may occur around:  Caves Chicken coops Old buildings Demolition sites Excavation Soil disruption  Most infections are:  Asymptomatic Mild respiratory infections  The ocular syndrome may become clinically apparent long after the presumed systemic exposure.

Pathogenesis The precise mechanism remains uncertain. A proposed sequence is: Prior systemic Histoplasma exposure → hematogenous seeding or immune-mediated choroidal injury → healed focal chorioretinal scars → later MNV in susceptible lesions However, viable fungal organisms are generally not demonstrable in classic POHS lesions. Thus the current concept favors:  Prior infectious trigger Subsequent inflammatory/chorioretinal scarring Late neovascular complications  rather than chronic active fungal infection.

Genetics Certain HLA associations have historically been reported, suggesting that: Host immune susceptibility may influence the development of POHS after Histoplasma exposure. Routine genetic testing has no clinical role.

Clinical Presentation Patients may be: Completely asymptomatic if lesions are peripheral or inactive. Symptoms usually arise when MNV develops near the macula. These may include:  Metamorphopsia Central blur Paracentral scotoma Micropsia Reduced central vision

Laterality POHS may be:  Unilateral clinically Bilateral  Even when symptoms occur in only one eye, the fellow eye may show:  Histo spots Peripapillary atrophy

Classic Fundus Triad The classic triad is:  Punched-out chorioretinal scars Peripapillary atrophy No vitritis  The absence of vitreous inflammation is particularly important diagnostically.

Histo Spots Histo spots are small, discrete, round or oval areas of:  Chorioretinal atrophy RPE disturbance  They are commonly:  Yellow-white when relatively fresh Pigmented or atrophic when healed  They may occur in:  Macula Midperiphery Peripheral retina

Macular Histo Spots Macular histo spots are clinically important because they increase the risk of: Secondary MNV which is the major cause of severe visual loss in POHS.

Peripapillary Atrophy Typical peripapillary findings include:  Circumferential or irregular chorioretinal atrophy Pigmentary alteration adjacent to the optic nerve  This may be subtle or extensive.

Histo Streaks Linear chorioretinal scars may occasionally be seen and have historically been called: Histo streaks These are less diagnostically important than the classic triad.

Absence of Inflammation Classic POHS lacks:  Anterior chamber cells Vitreous cells Vitreous haze  This feature helps distinguish it from inflammatory disorders such as: Multifocal choroiditis with panuveitis

Macular Neovascularization MNV may develop adjacent to:  Macular histo spots Peripapillary scars  Typical manifestations include:  Gray-green subretinal lesion Subretinal hemorrhage Intraretinal or subretinal fluid Lipid exudation Pigment epithelial detachment Fibrosis

Peripapillary MNV POHS may also produce: Peripapillary MNV which can enlarge toward:  Papillomacular bundle Fovea  and become visually significant.

Disciform Scar Untreated or chronic MNV may evolve into:  Fibrovascular scar Disciform macular scar  causing permanent central vision loss.

Diagnosis POHS is a: Clinical diagnosis There is no laboratory test that confirms classic ocular disease. Diagnosis rests on:  Characteristic fundus findings Lack of vitreous inflammation Compatible epidemiologic history Imaging when MNV is suspected

Laboratory Testing Routine testing for:  Histoplasma antibodies Serum antigen Urine antigen  is generally: Not useful for isolated POHS because these tests are designed primarily for diagnosing active systemic histoplasmosis.

Histoplasmin Skin Testing Histoplasmin skin testing is: Obsolete for routine ophthalmic diagnosis and should not be used to establish POHS.

Fundus Photography Fundus photography is useful for documenting:  Histo spots Peripapillary atrophy Hemorrhage Pigmentary change Scar progression

Optical Coherence Tomography OCT is the key modern structural test when MNV is suspected. It may demonstrate:  Subretinal hyperreflective material Subretinal fluid Intraretinal fluid RPE elevation Fibrosis Outer retinal atrophy  OCT is also useful for monitoring response to anti-VEGF therapy.

OCT Angiography OCTA can demonstrate a neovascular network without intravenous dye. It is useful for:  Detecting MNV Monitoring vascular activity Assessing lesions when fluorescein angiography is undesirable  However, OCTA should be interpreted alongside:  Structural OCT Clinical examination  because visible flow does not always indicate active exudation.

Fluorescein Angiography FA may show:  Early hyperfluorescence of classic MNV Progressive leakage in active lesions Window defects corresponding to atrophic histo spots  It remains useful when:  Diagnosis is uncertain Lesion activity needs clarification

Indocyanine Green Angiography ICG is rarely required for routine POHS. It may be useful when:  Choroidal pathology is atypical Differential diagnosis remains uncertain

Differential Diagnosis Important differentials include:  Multifocal choroiditis with panuveitis Punctate inner choroidopathy Pathologic myopia Age-related macular degeneration Angioid streaks Idiopathic MNV Other causes of multifocal chorioretinal scars Ocular toxoplasmosis Ocular tuberculosis Syphilitic chorioretinitis Active fungal chorioretinitis

POHS vs Multifocal Choroiditis This distinction is particularly important. POHS Typically:  Punched-out scars Peripapillary atrophy No vitritis MNV may occur  Multifocal Choroiditis with Panuveitis Typically:  Similar punched-out lesions Vitritis present May have anterior chamber inflammation Often inflammatory symptoms MNV may also occur  The presence of intraocular inflammation argues strongly against classic POHS.

POHS vs Punctate Inner Choroidopathy PIC usually occurs in:  Young myopic women  and produces:  Small yellow-white posterior pole lesions Little or no vitritis High risk of MNV  Unlike POHS, PIC generally lacks the classic combination of:  Widespread histo spots Peripapillary atrophy Endemic Histoplasma association

POHS vs Pathologic Myopia Myopic MNV occurs in eyes with:  High axial myopia Tessellated fundus Lacquer cracks Posterior staphyloma Myopic macular degeneration  These structural findings distinguish it from typical POHS.

POHS vs AMD AMD generally occurs in older adults and is associated with:  Drusen Pigment epithelial abnormalities Geographic atrophy  POHS typically lacks: Drusen as the central disease feature and occurs in a younger population.

Active Histoplasma Chorioretinitis An important distinction: Classic POHS is not the same as active ocular histoplasmosis in an immunocompromised patient. Disseminated histoplasmosis can occasionally produce:  Active chorioretinitis Systemic illness Multiorgan infection  especially in:  Advanced HIV Transplant recipients Other severely immunosuppressed patients  These patients require systemic infectious-disease evaluation and antifungal therapy.

Treatment Inactive POHS Without MNV No treatment is required for:  Inactive histo spots Stable peripapillary atrophy Asymptomatic scars  Management consists of:  Observation Patient education Surveillance for MNV

Antifungal Therapy Antifungal treatment is not indicated for classic POHS. The ocular syndrome does not represent proven active fungal replication. Antifungal therapy is reserved for: Active systemic or ocular histoplasmosis, not presumed ocular histoplasmosis syndrome.

Corticosteroids Routine corticosteroid treatment is: Not recommended for typical POHS because the classic syndrome lacks active intraocular inflammation. If active inflammatory choroiditis is present, reconsider whether the diagnosis is actually:  Multifocal choroiditis PIC Infectious choroiditis Another inflammatory disorder  rather than classic POHS.

Treatment of MNV The modern first-line treatment for POHS-associated MNV is: Intravitreal anti-VEGF therapy

Anti-VEGF Therapy Agents used include:  Bevacizumab Ranibizumab Aflibercept Other approved anti-VEGF agents depending on region and availability  Treatment usually produces:  Reduction in fluid Reduction in hemorrhage Stabilization or improvement of visual acuity

Treatment Strategy Treatment is individualized using:  OCT evidence of activity Visual acuity Hemorrhage Symptoms  Many patients require:  Several initial injections Followed by PRN or treat-and-extend style monitoring  The exact strategy depends on lesion behavior.

Anti-VEGF Prognosis POHS-associated MNV often responds: Very well to anti-VEGF therapy particularly when detected early before:  Foveal fibrosis Extensive atrophy

Thermal Laser Thermal laser photocoagulation was historically used for:  Extrafoveal MNV  but it is now rarely used because: Anti-VEGF therapy provides superior anatomic flexibility and avoids immediate laser scotoma.

Photodynamic Therapy Verteporfin PDT was also used historically. It has largely been superseded by: Anti-VEGF therapy but may occasionally have a role in unusual refractory cases.

Submacular Surgery Surgical removal of MNV was historically attempted. It is now: Obsolete for routine POHS-associated MNV because anti-VEGF therapy provides better risk-benefit balance.

Follow-Up Patients with inactive POHS should have periodic examination. Frequency depends on:  Presence of macular scars Fellow-eye history of MNV Symptoms Age Other macular disease  Annual follow-up is reasonable for many stable patients.

Higher-Risk Follow-Up More frequent review is appropriate when there is:  Previous MNV Macular histo spot Recent new symptoms Suspicious OCT changes Fellow-eye neovascular disease

Home Monitoring Patients should monitor central vision using:  Amsler grid Preferably monocularly  They should report immediately:  New distortion Wavy lines Central blur Missing areas New scotoma

Prognosis Patients without MNV usually maintain: Excellent vision because peripheral histo spots are often visually insignificant. Visual prognosis depends primarily on:  Development of MNV Location relative to fovea Speed of diagnosis Response to anti-VEGF Degree of residual fibrosis or atrophy

Fellow-Eye Risk Patients who develop MNV in one eye are at increased risk of:  MNV in the fellow eye  especially if the fellow eye contains:  Macular histo spots  Long-term bilateral surveillance is therefore important.

Complications The principal complication is: Macular neovascularization which can cause:  Subretinal hemorrhage Exudation Fibrosis Disciform scar Permanent central visual loss  Other POHS lesions usually remain stable.

Ophthalmology Pearls  POHS is diagnosed clinically by punched-out chorioretinal scars, peripapillary atrophy, and absence of vitritis. The classic lesions are called histo spots. POHS is strongly associated epidemiologically with prior Histoplasma capsulatum exposure, especially in the Ohio and Mississippi River valleys, but direct fungal causation within the eye is usually unproven. No vitreous inflammation is a key diagnostic feature; vitritis should make you reconsider multifocal choroiditis or another inflammatory/infectious process. Most patients are asymptomatic until macular neovascularization develops. MNV is the major cause of vision loss in POHS. Macular histo spots increase the risk of subsequent MNV. Routine Histoplasma serology, urine antigen, and skin testing are not useful for diagnosing classic POHS. OCT is central for detecting and monitoring MNV; OCTA and FA are useful adjuncts. Intravitreal anti-VEGF therapy is first-line treatment for POHS-associated MNV. Thermal laser, PDT, and submacular surgery are largely historical treatments in the anti-VEGF era. Antifungal therapy is not indicated for classic POHS, because it is not considered active ocular fungal infection. Classic POHS should be distinguished from disseminated histoplasmosis with active chorioretinitis in immunocompromised patients, which requires systemic antifungal treatment. Stable POHS without MNV requires observation, periodic follow-up, and home central-vision monitoring. New metamorphopsia or central blur should prompt urgent OCT evaluation for MNV.

Ophthalmology – Presbyopia

Basics

Description

Presbyopia is the age-related progressive loss of the eye’s ability to accommodate sufficiently for comfortable near vision.

It results in increasing difficulty focusing on:

• Small print
• Smartphones
• Reading material
• Near occupational tasks

while distance vision may remain normal if the patient is emmetropic or appropriately corrected.

The underlying problem is primarily:

Age-related loss of crystalline lens deformability together with changes in the lens–zonule–ciliary body system

rather than paralysis or weakness of the ciliary muscle.

Clinical Importance

Presbyopia is essentially universal with aging.

Typical presentation is:

Progressively increasing near working distance in a middle-aged patient with otherwise stable distance vision

Treatment is individualized according to:

• Distance refractive error
• Desired working distance
• Occupational demands
• Binocular function
• Ocular health
• Tolerance for optical compromise

Epidemiology

Presbyopic symptoms typically begin during the:

Early to mid-40s

but onset varies considerably.

Earlier symptoms may occur in:

• Hyperopes
• Patients performing prolonged near work
• Patients requiring very fine near vision
• Certain environmental or occupational conditions

Myopic patients may recognize symptoms later because they can often read comfortably after removing their distance glasses.

By the sixth decade, virtually everyone has significant reduction in accommodation.

Accommodation

Accommodation allows the eye to increase optical power for near viewing.

The conventional Helmholtz model remains the principal framework:

Ciliary muscle contraction → reduced zonular tension → crystalline lens becomes more convex → increased optical power

For distance:

Ciliary relaxation → increased zonular tension → lens becomes flatter

Pathophysiology of Presbyopia

Presbyopia is multifactorial.

Major age-related changes include:

• Progressive stiffening of the crystalline lens
• Increased lens thickness
• Continued lens fiber accumulation
• Altered lens capsule biomechanics
• Changes in zonular geometry
• Altered ciliary body–lens relationships

The ciliary muscle generally retains substantial contractile ability even in older adults.

Thus presbyopia is not simply:

“Ciliary muscle weakness.”

Crystalline Lens Stiffening

The most important factor is increasing mechanical stiffness of the crystalline lens.

With age:

• Lens proteins become increasingly compact
• Lens nucleus stiffens
• Lens shape becomes less responsive to changes in zonular tension

Consequently, ciliary muscle contraction produces progressively less change in lens curvature and power.

Accommodative Amplitude

Accommodation progressively declines from childhood onward.

Approximate values traditionally used for clinical teaching are:

• Childhood: >10 D
• Age 30: roughly 7–8 D
• Age 40: approximately 4–5 D
• Age 50: approximately 2 D
• Age 60+: approximately 1 D or less

There is substantial individual variation.

Near Demand

The accommodative demand is approximately the reciprocal of viewing distance in meters.

For example:

• 1 m → 1.00 D
• 50 cm → 2.00 D
• 40 cm → 2.50 D
• 33 cm → 3.00 D
• 25 cm → 4.00 D

A patient needs some accommodative reserve for sustained comfortable near work rather than using maximum accommodation continuously.

Symptoms

Typical symptoms include:

• Blurred near vision
• Need to hold reading material farther away
• Difficulty reading small print
• Reduced endurance for prolonged near work
• Eyestrain
• Frontal headache
• Difficulty in dim illumination
• Slower transition between near and distance focus

The classic complaint is:

“My arms are not long enough anymore.”

Effect of Illumination

Near vision often becomes worse in dim light because:

• The pupil enlarges
• Depth of focus decreases
• Contrast falls

Patients therefore frequently notice presbyopia first when:

• Reading restaurant menus
• Reading at night
• Performing fine near tasks under poor illumination

Refractive Status and Presbyopia

Emmetropia

The typical emmetrope develops:

• Good distance vision
• Increasingly blurred near vision

and eventually requires a near addition.

Hyperopia

Uncorrected hyperopes use accommodation even for distance.

Therefore they often notice presbyopic symptoms:

Earlier

because part of their accommodative reserve is already being used to overcome hyperopia.

Latent hyperopia may become clinically apparent as presbyopia develops.

Myopia

Uncorrected myopes can often continue reading at near by removing their distance spectacles.

The near focal distance depends approximately on the amount of myopia.

For example:

• −2.50 D myope → clear focus around 40 cm without spectacles

Therefore myopes may appear to develop presbyopia later, although their actual accommodative decline still occurs.

Myopia: Glasses vs Contact Lenses

A myopic presbyope may find near work harder in:

Contact lenses than spectacles

because contact lenses remove the spectacle-related reduction in accommodative demand.

Thus a pre-presbyopic myope may read adequately through spectacles but become symptomatic when switched to full distance correction with contact lenses.

Hyperopia: Glasses vs Contact Lenses

The opposite optical effect occurs in hyperopia.

Hyperopic contact lens wear can slightly alter near accommodative and vergence demands compared with spectacle correction.

Astigmatism

Uncorrected or undercorrected astigmatism may:

• Reduce near clarity
• Produce eyestrain
• Make presbyopic symptoms appear worse

A complete refraction should therefore precede determination of the near addition.

Diagnosis

Presbyopia is usually diagnosed clinically from:

• Age
• Symptoms
• Distance refraction
• Near visual performance

No laboratory or imaging investigation is required.

History

Ask about:

• Reading distance
• Computer distance
• Smartphone use
• Occupational tasks
• Duration of near work
• Lighting conditions
• Existing spectacles
• Previous bifocal/progressive use
• Contact lens use
• Desired spectacle independence

The required near addition should be based on the patient’s:

Actual working distance, not age alone.

Distance Refraction

Perform an accurate distance refraction first.

This is particularly important because apparent presbyopic symptoms may actually reflect:

• Uncorrected hyperopia
• Astigmatism
• Over-minus correction
• Changing refractive error

Near Visual Acuity

Near acuity should be measured at the patient’s:

Habitual working distance

rather than automatically at 40 cm.

Examples:

• Desktop computer: often 50–70 cm
• Reading: 35–45 cm
• Smartphone: often 30–40 cm
• Fine technical work: may be closer

Near Addition

The near add is the additional plus power placed over the distance correction to reduce accommodative demand.

It should provide:

• Clear near vision
• Comfortable sustained viewing
• Useful range of focus

Excessive plus power:

• Shortens the working distance
• Narrows the useful range of clear vision

Therefore the lowest comfortable add is usually preferred.

Age-Based Add Values

Age-based values can provide a starting estimate, but should not replace clinical measurement.

Approximate commonly encountered ranges are:

• Early 40s: +0.75 to +1.25 D
• Mid-to-late 40s: +1.25 to +1.75 D
• Early 50s: +1.75 to +2.00 D
• Late 50s: +2.00 to +2.25 D
• Around 60+: approximately +2.25 to +2.50 D for a 40-cm reading distance

Actual requirements vary considerably.

Amplitude of Accommodation

Accommodation may be measured using:

• Push-up method
• Push-down method
• Minus-lens method
• Dynamic retinoscopy

These are most helpful when:

• Symptoms are atypical
• Presbyopia appears unusually early
• Accommodative insufficiency is suspected

Push-Up Method

With distance correction in place:

• A near target is moved toward the eye
• The patient reports sustained blur
• Near point is converted to diopters

This method tends to:

Overestimate true accommodative amplitude

because angular magnification of the approaching target makes blur harder to detect.

Minus-Lens Method

With the near target at a fixed distance:

• Increasing minus power stimulates accommodation
• Minus is added until sustained blur

The fixed working-distance demand is added to the minus lens power.

This method may underestimate accommodation compared with the push-up technique.

Binocular Vision Assessment

If symptoms are disproportionate to presbyopia, evaluate for:

• Convergence insufficiency
• Accommodative insufficiency
• Decompensated phoria
• Ocular surface disease
• Early cataract

Near symptoms should not automatically be attributed to presbyopia.

Differential Diagnosis

Important alternatives or contributors include:

• Uncorrected hyperopia
• Astigmatism
• Accommodative insufficiency
• Convergence insufficiency
• Dry eye disease
• Cataract
• Medication-induced cycloplegia
• Third-nerve dysfunction
• Adie’s tonic pupil
• Other neurologic causes of accommodative paresis

Treatment Principles

Treatment aims to provide useful near focus while preserving acceptable:

• Distance vision
• Intermediate vision
• Contrast
• Binocular function
• Stereopsis

No single strategy is ideal for every patient.

Spectacle Correction

Spectacles remain the:

Safest, most predictable, and most versatile treatment

for presbyopia.

Options include:

• Over-the-counter readers
• Prescription single-vision near glasses
• Bifocals
• Trifocals
• Progressive addition lenses
• Occupational/computer lenses

Over-the-Counter Readers

OTC readers are appropriate for patients with:

• Minimal distance refractive error
• Minimal astigmatism
• Little anisometropia
• Similar near requirement in both eyes

Disadvantages include:

• Same power in both eyes
• No astigmatic correction
• No prism or anisometropic correction

Single-Vision Near Spectacles

These provide a large, clear near field.

They are especially useful for:

• Prolonged reading
• Fine near work
• Patients who dislike multifocal lenses

Disadvantage:

• Distance becomes blurred while wearing them

Bifocals

Bifocals provide:

• Distance correction superiorly
• Near correction through a distinct lower segment

Advantages include:

• Wide, stable near zone
• Easy identification of near segment

Disadvantages include:

• Image jump
• Visible segment
• Limited intermediate range

Trifocals

Trifocals add an:

Intermediate segment

between distance and near.

They can be useful for:

• Desktop computer work
• Occupational tasks

but have largely been replaced by progressive lenses in many patients.

Progressive Addition Lenses

Progressive lenses provide a gradual transition from:

• Distance
• Intermediate
• Near

without a visible segment line.

Advantages:

• Functional vision over multiple distances
• Better cosmesis

Limitations:

• Peripheral distortion
• Smaller near/intermediate corridors
• Adaptation period
• Greater sensitivity to fitting accuracy

Occupational / Office Lenses

Computer or occupational progressive lenses can provide:

• Wide intermediate field
• Wide near field

They are often superior to general-purpose progressives for patients spending long periods at:

• Desktop computers
• Workstations

They usually sacrifice full-distance vision.

Contact Lens Correction

Options include:

• Monovision
• Multifocal contact lenses
• Modified monovision

Monovision

Typically:

• Dominant eye corrected for distance
• Nondominant eye corrected for near

Advantages:

• Simple
• Relatively inexpensive
• Can provide substantial spectacle independence

Monovision Limitations

Possible disadvantages include:

• Reduced stereopsis
• Reduced contrast sensitivity
• Less precise depth perception
• Difficulty with night driving
• Reduced binocular summation

Tolerance varies greatly.

A contact lens monovision trial is strongly recommended before permanent surgical monovision.

Multifocal Contact Lenses

Modern multifocal lenses commonly use:

• Simultaneous-vision optics
• Center-near or center-distance designs
• Aspheric power profiles

They can provide:

• Distance
• Intermediate
• Near vision

but may reduce:

• Contrast
• Image quality

particularly in low light.

Modified Monovision

One eye may receive:

• Distance-biased multifocal correction

while the other receives:

• Near-biased correction

This can sometimes improve functional range compared with conventional monovision.

Pharmacologic Treatment

Presbyopia can also be treated temporarily with:

Miotic ophthalmic drops

that reduce pupil diameter and increase:

Depth of focus through a pinhole effect

Some agents may also stimulate limited accommodation.

Pilocarpine

Low-concentration pilocarpine formulations can improve near vision for several hours in selected presbyopic adults.

Potential adverse effects include:

• Headache
• Brow ache
• Eye ache
• Conjunctival hyperemia
• Dimmer vision in low light
• Temporary myopic shift
• Reduced night vision

Retinal Safety With Miotics

Rare retinal complications including:

• Retinal tear
• Retinal detachment

have been reported with miotic therapy.

Particular caution is appropriate in patients with:

• High myopia
• Lattice degeneration
• Previous retinal tear
• Previous retinal detachment

A dilated retinal examination may be appropriate before treatment in higher-risk patients.

Patients should report immediately:

• New flashes
• New floaters
• Curtain or shadow

Newer Miotic Therapies

Newer presbyopia drops are designed to produce:

• Controlled pupillary constriction
• Increased depth of focus

with less accommodative spasm than traditional pilocarpine in some formulations.

These treatments provide:

Temporary functional improvement rather than restoration of youthful accommodation.

They are most useful in carefully selected patients who desire intermittent spectacle independence.

Limitations of Pharmacologic Therapy

Miotic drops do not:

• Reverse crystalline lens aging
• Restore normal youthful accommodation
• Permanently treat presbyopia

Their benefit lasts only while the pharmacologic effect is active.

Surgical Correction

Presbyopia surgery requires careful counseling because virtually every surgical strategy involves tradeoffs among:

• Near acuity
• Distance acuity
• Contrast sensitivity
• Stereopsis
• Dysphotopsia
• Optical quality

Corneal Monovision

LASIK or PRK may create:

Surgical monovision

in appropriately selected patients.

A successful preoperative contact lens trial is highly desirable.

PresbyLASIK

Some corneal ablation profiles create multifocal or increased depth-of-focus corneal optics.

Potential problems include:

• Halos
• Glare
• Reduced contrast
• Regression
• Difficult future IOL calculations

Use varies by region and technology.

Corneal Inlays

Corneal inlays were developed to:

• Increase depth of focus
• Provide central near power

However, enthusiasm has declined substantially because of complications such as:

• Corneal haze
• Stromal remodeling
• Visual quality problems
• Need for explantation

They are no longer a major mainstream strategy.

Scleral Expansion Procedures

Historical scleral expansion procedures were intended to modify:

• Ciliary body–lens geometry

Results were inconsistent.

They are:

Not accepted standard treatment for presbyopia.

Lens-Based Treatment

Lens-based correction is particularly relevant in patients with:

• Cataract
• Significant lens dysfunction
• Desire for spectacle independence

Options include:

• Monofocal monovision
• Multifocal IOL
• Trifocal IOL
• Extended-depth-of-focus IOL
• Selected accommodating IOL technologies

Monofocal IOL Monovision

At cataract surgery, one eye may be targeted for:

• Distance

and the fellow eye for:

• Mild myopia / near or intermediate vision

Advantages include:

• Good optical quality
• Lower dysphotopsia than many multifocal lenses

Disadvantage:

• Reduced stereopsis

Multifocal / Trifocal IOLs

These divide incoming light among multiple focal points.

They can provide:

• Distance
• Intermediate
• Near vision

Potential disadvantages include:

• Halos
• Glare
• Reduced contrast sensitivity
• Night-driving difficulties
• Residual refractive error intolerance

Extended-Depth-of-Focus IOLs

EDOF IOLs extend the range of clear vision, particularly:

• Distance
• Intermediate

Some provide functional near vision but generally less strong near performance than high-add multifocal/trifocal lenses.

They may produce:

• Less dysphotopsia than some multifocal designs

but tradeoffs remain.

Accommodating IOLs

Accommodating IOLs attempt to produce dynamic changes in effective lens power.

Traditional designs have generally provided:

Limited and variable true accommodative amplitude

and have not reproduced youthful accommodation.

Newer technologies continue to evolve.

Patient Selection for Presbyopia-Correcting IOLs

Careful screening is essential.

Conditions that may reduce satisfaction include:

• Irregular astigmatism
• Significant dry eye
• Corneal dystrophy
• Advanced glaucoma
• Macular disease
• Epiretinal membrane
• Optic neuropathy

Patients with high visual-quality demands, especially night driving, require particularly careful counseling.

Refractive Lens Exchange

Clear-lens extraction with presbyopia-correcting IOLs may be considered in selected patients.

However, it involves intraocular surgical risks including:

• Endophthalmitis
• Retinal detachment
• Cystoid macular edema
• Dysphotopsia
• Residual refractive error

In younger high myopes, retinal detachment risk deserves particular consideration.

Prevention

There is no established evidence that presbyopia can be prevented or meaningfully delayed through:

• Eye exercises
• Vitamins
• Dietary supplements
• Reading techniques

Presbyopia reflects normal age-related ocular biomechanics.

Follow-Up

Presbyopic correction should be reassessed when the patient develops:

• Increasing near blur
• Changed working distance
• Difficulty at intermediate distances
• New distance refractive error
• Cataract symptoms

Near addition typically increases gradually until accommodative reserve becomes minimal.

Prescribing Principle

Do not prescribe near power based only on:

Chronologic age

The prescription should consider:

• Distance refraction
• Working distance
• Remaining accommodation
• Occupational needs
• Previous correction
• Patient preference

Near Testing and Dilation

Near accommodative testing should be performed:

Before pharmacologic dilation

because cycloplegic or mydriatic agents can alter:

• Accommodation
• Pupil size
• Near visual performance

Prognosis

Presbyopia progresses gradually as accommodation declines.

Eventually:

• Little useful accommodative amplitude remains

but the exact age and required near addition vary among individuals.

For a 40-cm reading distance, many fully presbyopic patients use an add near:

+2.50 D

but this is not an absolute ceiling.

Higher add powers may be appropriate for:

• Closer working distances
• Reduced visual acuity
• Low-vision magnification
• Specific occupational tasks

Important Correction – Maximum Add

The older concept that a patient “should never need more than +2.50 D” is incorrect.

Additional plus:

• Shortens the focal distance
• Provides optical magnification

and can be entirely appropriate when clinically required.

Ophthalmology Pearls

• Presbyopia is the age-related loss of accommodation caused mainly by increasing crystalline lens stiffness and altered lens–zonule biomechanics.
• Symptoms usually begin in the early to mid-40s, but onset varies with refractive error and visual demand.
• Hyperopes generally become symptomatic earlier; myopes can often read by removing their distance spectacles.
• A 40-cm working distance requires approximately 2.50 D of near focusing power.
• Prescribe the lowest near add that provides comfortable sustained vision at the patient’s actual working distance.
• Age-based add values are only a starting point; near correction should be individualized.
• Spectacles remain the safest and most predictable treatment, with readers, bifocals, progressives, and occupational lenses chosen according to task.
• Monovision can provide spectacle independence but compromises stereopsis and binocular image quality; trial it with contact lenses before permanent surgical monovision.
• Modern multifocal contact lenses provide useful distance/intermediate/near vision but may reduce contrast.
• Miotic presbyopia drops improve near vision primarily by increasing depth of focus, but they do not restore youthful accommodation and may cause headache, dim vision, or rarely retinal complications.
• Presbyopia-correcting IOL options include monovision, multifocal/trifocal, and EDOF lenses, each with specific optical tradeoffs.
• Multifocal and EDOF IOL candidates require careful assessment of the cornea, ocular surface, macula, optic nerve, and glaucoma status.
• Corneal inlays and scleral expansion procedures have largely fallen out of mainstream use because of limited efficacy or complications.
• There is no proven exercise, vitamin, diet, or lens strategy that prevents presbyopia.
• Near testing should be performed before dilation because mydriatic/cycloplegic agents can alter accommodation and near performance.

Ophthalmology – Pregnancy and Ophthalmic Disease

Basics

Description

Pregnancy produces physiologic, vascular, hormonal, metabolic, and immunologic changes that may:

• Alter normal ocular physiology
• Exacerbate preexisting eye disease
• Produce pregnancy-specific retinal or neuro-ophthalmic manifestations
• Modify the safety and timing of ophthalmic investigations and treatment

Important ophthalmic disorders associated with pregnancy include:

• Preeclampsia/eclampsia and posterior reversible encephalopathy syndrome (PRES)
• Diabetic retinopathy
• Central serous chorioretinopathy
• Retinal vascular occlusion
• Purtscher-like retinopathy
• Pituitary enlargement/apoplexy
• Meningioma enlargement
• Hypercoagulability-related disease

Visual symptoms during pregnancy may occasionally signal a:

Potentially life-threatening obstetric or neurologic emergency.

⸻

Physiologic Ocular Changes in Pregnancy

Normal pregnancy can produce several reversible ocular changes.

⸻

Corneal Changes

Pregnancy may cause:

• Increased corneal thickness
• Mild corneal edema
• Increased corneal curvature
• Reduced corneal sensitivity
• Contact lens intolerance

These changes can produce:

• Temporary refractive fluctuation
• Blurred vision

They generally resolve postpartum.

⸻

Refractive Changes

Transient shifts may occur because of:

• Corneal hydration
• Curvature changes
• Lens changes

Therefore:

Avoid prescribing a major new permanent spectacle correction solely for a pregnancy-related refractive shift when possible.

Stable refraction can be reassessed several weeks to months postpartum.

⸻

Refractive Surgery

Elective refractive surgery is generally deferred during:

• Pregnancy
• Early postpartum period
• Often lactation until refraction stabilizes

because corneal and refractive parameters may fluctuate.

⸻

Accommodation

Some patients experience:

• Transient accommodative insufficiency
• Difficulty with near vision

Symptoms generally resolve postpartum.

⸻

Intraocular Pressure

IOP commonly:

Falls during pregnancy

particularly in the second and third trimesters.

Possible mechanisms include:

• Increased aqueous outflow
• Hormonal effects
• Reduced episcleral venous pressure

IOP usually returns toward baseline after delivery.

⸻

Dry Eye

Pregnancy can alter the tear film and meibomian gland function, producing:

• Dry eye
• Contact lens intolerance
• Burning or foreign-body sensation

Treatment generally includes:

• Preservative-free artificial tears
• Lid hygiene when appropriate

⸻

Preeclampsia

Modern Definition

Preeclampsia develops after approximately:

20 weeks of gestation

and is characterized by new-onset hypertension plus either:

• Proteinuria

or evidence of maternal organ dysfunction such as:

• Thrombocytopenia
• Renal impairment
• Liver dysfunction
• Pulmonary edema
• Cerebral or visual symptoms

Therefore:

Proteinuria is not required for the diagnosis if other severe features are present.

⸻

Eclampsia

Eclampsia refers to:

Preeclampsia associated with:

New-onset generalized seizures not attributable to another cause.

⸻

Ophthalmic Importance of Preeclampsia

Visual symptoms are important because they may represent:

• Severe hypertensive retinopathy
• Choroidal ischemia
• Serous retinal detachment
• Optic neuropathy
• PRES
• Stroke

Any pregnant patient with:

• New blurred vision
• Scotoma
• Photopsia
• Diplopia
• Severe headache

in the setting of hypertension requires urgent obstetric and medical evaluation.

⸻

Ocular Findings in Preeclampsia

Possible findings include:

• Retinal arteriolar narrowing
• Arteriolar vasospasm
• Retinal hemorrhages
• Cotton-wool spots
• Hard exudates
• Optic disc edema
• Choroidal ischemia
• Serous retinal detachment

⸻

Serous Retinal Detachment

Serous retinal detachment is an uncommon but classic severe manifestation of:

• Preeclampsia
• Eclampsia
• HELLP syndrome

It is caused primarily by:

Choroidal vascular compromise → RPE dysfunction → subretinal fluid accumulation

It is often:

• Bilateral
• Bullous in severe cases

⸻

Prognosis of Preeclamptic Serous Detachment

Most cases improve after:

• Blood pressure stabilization
• Treatment of preeclampsia
• Delivery when indicated

Subretinal fluid frequently resolves over:

• Days to weeks

Persistent RPE pigmentary changes may remain.

⸻

Hypertensive Choroidopathy

Findings may include:

• Elschnig spots
• Siegrist streaks
• Serous retinal detachment

These result from:

Choroidal ischemia

rather than primary retinal disease.

⸻

Posterior Reversible Encephalopathy Syndrome

The older term “preeclampsia/eclampsia hypertensive posterior encephalopathy syndrome” is now generally encompassed by:

Posterior reversible encephalopathy syndrome (PRES)

⸻

PRES

PRES may occur with:

• Preeclampsia
• Eclampsia
• Severe hypertension

Symptoms include:

• Headache
• Seizures
• Altered mental status
• Visual disturbance
• Cortical blindness

⸻

Visual Findings in PRES

Patients may experience:

• Bilateral blurred vision
• Homonymous field defects
• Visual neglect
• Cortical blindness

The pupils and ocular examination may remain:

Normal

because the visual deficit is retrochiasmal.

⸻

MRI in PRES

MRI typically demonstrates:

• Vasogenic edema

predominantly involving:

• Parieto-occipital white matter

although other regions may be involved.

MRI is preferred when clinically feasible.

⸻

Cortical Blindness in Preeclampsia

Visual loss can result from:

• PRES
• Occipital ischemia or infarction

In reversible PRES:

• Visual recovery can be excellent

after maternal stabilization.

⸻

HELLP Syndrome

HELLP stands for:

• Hemolysis
• ELevated liver enzymes
• LP low platelet count

It is a severe pregnancy-related hypertensive disorder.

⸻

Ocular Findings in HELLP

Reported manifestations include:

• Serous retinal detachment
• Choroidal ischemia
• Retinal hemorrhage
• Cotton-wool spots
• Vitreous hemorrhage
• Purtscher-like retinopathy

Visual symptoms require urgent systemic assessment.

⸻

Diabetic Retinopathy and Pregnancy

Pregnancy can accelerate progression of:

Preexisting diabetic retinopathy

particularly in patients with:

• Type 1 diabetes
• Type 2 diabetes

⸻

Gestational Diabetes

Gestational diabetes that begins during pregnancy:

Does not itself cause diabetic retinopathy during that pregnancy

because the duration of hyperglycemia is too short.

However, if diabetes may have existed before pregnancy:

• A retinal examination is appropriate

because previously undiagnosed pregestational diabetes may already have caused retinopathy.

⸻

Risk Factors for Diabetic Retinopathy Progression

Progression is more likely with:

• More severe retinopathy at conception
• Longer duration of diabetes
• Poor preconception glycemic control
• Rapid improvement of markedly elevated glucose
• Hypertension
• Renal disease
• Poor glycemic control during pregnancy

⸻

Rapid Glycemic Improvement

Rapid normalization of severe hyperglycemia can produce:

Transient early worsening of diabetic retinopathy

This is not a reason to avoid appropriate glucose control, but patients with significant baseline retinopathy require close ophthalmic surveillance.

⸻

Screening Before or During Pregnancy

Women with known pregestational diabetes should ideally receive a dilated retinal examination:

• Before conception

or:

• Early in the first trimester

if not evaluated preconception.

⸻

Follow-Up in Diabetic Retinopathy

Follow-up frequency is based on baseline disease severity.

No or Minimal Retinopathy

May require:

• One or more examinations during pregnancy

depending on systemic control and guideline used.

Mild–Moderate NPDR

Usually requires:

• Closer surveillance during pregnancy

Severe NPDR or PDR

Requires:

• Frequent retina follow-up
• Often every 1–3 months or more frequently depending on activity

⸻

Diabetic Retinopathy Postpartum

Pregnancy-related progression may partially regress postpartum.

However:

Postpartum regression should not be assumed.

Patients with significant retinopathy require continued follow-up after delivery.

⸻

Proliferative Diabetic Retinopathy

PDR can worsen rapidly during pregnancy.

Treatment of active high-risk PDR is usually:

Panretinal photocoagulation (PRP)

Because pregnancy may accelerate disease, PRP is often performed:

• Promptly
• Sometimes earlier than in a comparable nonpregnant patient

when significant proliferative disease is present.

⸻

Anti-VEGF in Pregnancy

Intravitreal anti-VEGF therapy is generally:

Avoided when an effective alternative exists

because systemic VEGF signaling is important for:

• Placental development
• Fetal vascular development

and pregnancy safety data remain limited.

When sight is threatened and alternatives are inadequate, treatment requires individualized discussion with:

• Retina specialist
• Obstetrician
• Maternal-fetal medicine specialist

⸻

Diabetic Macular Edema

DME may:

• Develop
• Worsen
• Occasionally regress postpartum

Management depends on severity.

Options may include:

• Observation for mild cases
• Focal/grid laser in selected cases
• Intravitreal corticosteroid in carefully selected sight-threatening cases

Anti-VEGF is generally avoided when possible during pregnancy.

⸻

Delivery and Diabetic Retinopathy

An important modern correction:

Diabetic retinopathy or PDR alone is not usually an indication for cesarean delivery.

Normal vaginal delivery is generally acceptable.

A cesarean section should be based on:

Obstetric indications, not simply concern about Valsalva-induced vitreous hemorrhage.

⸻

Valsalva Retinopathy

Pregnancy and labor can occasionally produce:

Valsalva retinopathy

from sudden increased intrathoracic pressure.

Findings include:

• Preretinal hemorrhage
• Subhyaloid hemorrhage
• Sudden painless visual loss

Most cases resolve spontaneously.

⸻

Central Serous Chorioretinopathy

Pregnancy is a recognized risk factor for:

Central serous chorioretinopathy (CSCR)

probably related to:

• Elevated endogenous corticosteroid levels
• Choroidal vascular changes

⸻

Timing of Pregnancy-Associated CSCR

CSCR occurs most commonly in:

Late pregnancy, especially the third trimester

⸻

Clinical Findings

Patients may report:

• Central blur
• Metamorphopsia
• Micropsia
• Relative scotoma

OCT demonstrates:

Serous neurosensory retinal detachment

⸻

Subretinal Fibrin

Pregnancy-associated CSCR may show:

• Subretinal fibrinous material

more often than typical CSCR outside pregnancy.

This can sometimes mimic:

• Inflammatory disease
• Choroidal neovascularization

⸻

Treatment of Pregnancy-Associated CSCR

Most cases are:

Observed

because spontaneous resolution commonly occurs:

• Near delivery
• During the postpartum period

Avoid exogenous corticosteroids when clinically feasible.

⸻

Retinal Vascular Occlusion

Pregnancy creates a relatively:

Hypercoagulable state

which can contribute to:

• Retinal artery occlusion
• Retinal vein occlusion
• Cerebral venous thrombosis

especially in patients with additional thrombotic risk factors.

⸻

Hypercoagulability

Pregnancy physiologically increases:

• Several clotting factors

while reducing some anticoagulant and fibrinolytic activity.

This protects against obstetric hemorrhage but increases thrombotic risk.

⸻

Retinal Artery Occlusion

Acute monocular visual loss from retinal artery occlusion requires urgent investigation for:

• Embolic disease
• Thrombophilia
• Cardiac disease
• Preeclampsia
• Systemic vascular disease

Pregnancy alone should not automatically be assumed to be the cause.

⸻

Retinal Vein Occlusion

Retinal vein occlusion is uncommon but may occur with:

• Hypercoagulability
• Hypertension
• Preeclampsia
• Thrombophilic disorders

Management is individualized because usual intravitreal anti-VEGF therapy raises pregnancy-specific concerns.

⸻

Disseminated Intravascular Coagulation

DIC may occur with:

• Placental abruption
• Severe preeclampsia
• Amniotic fluid embolism
• Sepsis
• Retained fetal demise
• Major obstetric hemorrhage

⸻

Ocular DIC

Ocular manifestations may include:

• Retinal hemorrhage
• Cotton-wool spots
• Choroidal vascular occlusion
• Serous retinal detachment
• RPE changes

Systemic management is the priority.

⸻

Thrombotic Thrombocytopenic Purpura

TTP is characterized by:

• Microangiopathic hemolytic anemia
• Thrombocytopenia

with variable:

• Neurologic dysfunction
• Renal involvement
• Fever

Pregnancy can trigger or exacerbate TTP.

⸻

Ocular Findings in TTP

Possible manifestations include:

• Retinal hemorrhages
• Cotton-wool spots
• Retinal vascular occlusion
• Purtscher-like retinopathy
• Serous retinal detachment

TTP is a:

Medical emergency

requiring urgent hematologic management.

⸻

Purtscher-Like Retinopathy

Purtscher-like retinopathy may occur with:

• Preeclampsia
• HELLP
• TTP
• Pancreatitis
• Renal failure
• Other severe systemic conditions

⸻

Clinical Findings

Typical fundus findings include:

• Purtscher flecken
• Cotton-wool spots
• Retinal hemorrhages

usually clustered around the:

• Optic disc
• Posterior pole

⸻

Amniotic Fluid Embolism

Amniotic fluid embolism is a rare but catastrophic obstetric emergency characterized by sudden:

• Hypoxia
• Hypotension
• Cardiovascular collapse
• DIC

Ocular vascular occlusions may occur but are not the defining manifestation.

Modern survival is substantially better than the extreme mortality rates quoted in older literature, although the condition remains highly dangerous.

⸻

Pituitary Enlargement During Pregnancy

The pituitary normally enlarges during pregnancy because of:

Lactotroph hyperplasia

This physiologic enlargement is usually asymptomatic.

Preexisting pituitary tumors, especially macroadenomas, may enlarge sufficiently to affect:

• Optic chiasm
• Cavernous sinus

⸻

Pituitary Apoplexy

Pituitary apoplexy is:

Acute hemorrhage or infarction within the pituitary, usually in an adenoma

and is an endocrine and neuro-ophthalmic emergency.

⸻

Symptoms of Pituitary Apoplexy

Classic symptoms include:

• Sudden severe headache
• Nausea/vomiting
• Reduced vision
• Bitemporal visual field loss
• Ophthalmoplegia
• Ptosis

Cranial nerves:

• III
• IV
• VI

may be affected within the cavernous sinus.

⸻

Pituitary Apoplexy Examination

Assess urgently:

• Visual acuity
• Pupils
• Color vision
• Visual fields
• Ocular motility
• Optic nerves

⸻

MRI in Pituitary Apoplexy

Preferred imaging is:

Urgent MRI of the pituitary/sella

when available.

CT may be used when MRI is unavailable or contraindicated.

⸻

Systemic Management of Pituitary Apoplexy

Immediate management includes:

• Hemodynamic stabilization
• Electrolyte assessment
• Endocrine testing
• Stress-dose corticosteroids when adrenal insufficiency is suspected
• Neurosurgical and endocrinologic consultation

⸻

Pituitary Surgery

Transsphenoidal decompression may be required when there is:

• Severe or progressive visual impairment
• Significant visual field loss
• Progressive ophthalmoplegia
• Neurologic deterioration

Some stable cases can be managed conservatively under close multidisciplinary supervision.

⸻

Sheehan Syndrome

An important correction:

Sheehan syndrome is not simply postpartum pituitary apoplexy.

It is postpartum ischemic necrosis of the enlarged anterior pituitary, typically following:

• Severe postpartum hemorrhage
• Profound hypotension

Clinical manifestations may include:

• Failure to lactate
• Amenorrhea
• Hypothyroidism
• Adrenal insufficiency

⸻

Meningioma and Pregnancy

Some meningiomas enlarge during pregnancy because of:

• Hormonal influences
• Increased vascularity
• Fluid shifts

Symptoms may include:

• Visual loss
• Optic neuropathy
• Visual field defects
• Proptosis with orbital lesions
• Cranial neuropathies

Some tumors decrease in size postpartum.

⸻

Idiopathic Intracranial Hypertension

IIH may occur during pregnancy but pregnancy itself is not considered a primary cause.

Management principles remain centered on:

• Visual preservation
• Optic nerve monitoring

Acetazolamide may be considered when benefits justify use, especially after discussion with obstetric specialists.

⸻

Multiple Sclerosis and Optic Neuritis

MS relapse rates generally:

• Decrease during late pregnancy
• Increase during the early postpartum period

Acute optic neuritis during pregnancy is evaluated similarly to nonpregnant patients, with imaging and treatment individualized.

⸻

Graves Orbitopathy

Autoimmune thyroid disease may:

• Improve during pregnancy because of relative immunosuppression
• Flare postpartum

Thyroid status requires coordinated endocrine and obstetric management.

⸻

Keratoconus and Ectasia

Hormonal changes may alter corneal biomechanics.

Some patients with keratoconus may demonstrate:

• Increased steepening
• Progression

during pregnancy.

Patients with known ectasia who report visual change may benefit from:

• Topography/tomography

⸻

Diagnostic Evaluation of Visual Symptoms

Evaluation should be determined by the suspected disorder but may include:

• Visual acuity
• Pupils
• Color vision
• Visual fields
• IOP
• Slit-lamp examination
• Dilated fundus examination
• OCT

Check systemic status when appropriate, especially:

Blood pressure

⸻

OCT

OCT is:

• Noninvasive
• Nonionizing

and is considered safe during pregnancy.

It is particularly useful for:

• DME
• CSCR
• Serous retinal detachment
• Optic nerve disease

⸻

OCT Angiography

OCTA avoids intravenous dye and can be useful for evaluating:

• Retinal vasculature
• Choroidal neovascularization

It is noninvasive and particularly attractive during pregnancy when conventional angiography can be avoided.

⸻

Fluorescein Angiography

Fluorescein:

• Crosses the placenta
• Enters breast milk

No strong evidence proves major teratogenicity, but pregnancy safety data are limited.

Therefore FA is usually:

Avoided unless the diagnostic information is important for sight-threatening disease.

⸻

Indocyanine Green Angiography

Pregnancy data for ICG are limited.

ICG should generally be:

• Avoided if unnecessary
• Used when clinically important and benefits outweigh uncertainty

⸻

MRI

MRI without contrast is generally the preferred cross-sectional imaging modality when:

• Neuro-ophthalmic disease
• Pituitary disease
• PRES
• Intracranial mass

is suspected.

⸻

Gadolinium

Gadolinium crosses the placenta.

It is generally:

Avoided during pregnancy unless essential for diagnosis and expected to materially alter management.

⸻

CT

CT is not absolutely contraindicated when urgently needed.

For:

• Stroke
• Hemorrhage
• Trauma
• Other emergencies

necessary maternal imaging should not be withheld solely because of pregnancy.

Radiation exposure should be minimized appropriately.

⸻

Ophthalmic Medications in Pregnancy

General principles include:

• Use medication only when clinically indicated
• Use the lowest effective dose
• Prefer topical over systemic therapy when appropriate
• Reduce systemic absorption with punctal occlusion

⸻

Punctal Occlusion

After instilling an eye drop:

• Close the eyelids
• Apply gentle nasolacrimal pressure for approximately 1–2 minutes

This can reduce:

Systemic drug absorption

⸻

Topical Beta-Blockers

Timolol can cross systemically.

Potential fetal/neonatal concerns include:

• Bradycardia
• Hypotension
• Respiratory depression

When required:

• Use the lowest effective dose
• Consider gel formulations
• Use punctal occlusion

⸻

Brimonidine

Brimonidine has historically been considered relatively acceptable during pregnancy, but should generally be:

Avoided near delivery and during breastfeeding

because it can cause:

• CNS depression
• Apnea

in neonates and young infants.

⸻

Topical Carbonic Anhydrase Inhibitors

Dorzolamide and brinzolamide may be considered when necessary.

Systemic exposure is substantially lower than with oral therapy.

⸻

Acetazolamide

Systemic acetazolamide has traditionally been avoided during early pregnancy when alternatives exist.

However, human evidence has not demonstrated a strong teratogenic signal, and it may be used when:

Maternal visual benefit outweighs theoretical fetal risk

after multidisciplinary discussion.

⸻

Prostaglandin Analogs

Prostaglandin analogs have theoretical concerns related to:

• Uterine smooth-muscle activity

Systemic exposure from ophthalmic dosing is very low, but they are commonly avoided when satisfactory alternatives are available.

⸻

Miotics

Pilocarpine has relatively limited systemic exposure with topical use and may be considered when clinically necessary.

⸻

Topical Corticosteroids

Topical ophthalmic corticosteroids are generally usable when indicated because systemic exposure is low.

Monitor usual ocular adverse effects:

• IOP elevation
• Cataract
• Infection

⸻

Anti-VEGF Therapy

Intravitreal:

• Bevacizumab
• Ranibizumab
• Aflibercept
• Faricimab

are generally avoided during pregnancy when other reasonable treatments exist.

The concern is systemic VEGF suppression during:

• Placental vascular development
• Fetal organogenesis

Treatment of vision-threatening disease requires individualized risk–benefit discussion.

⸻

Laser Treatment

Ophthalmic laser procedures such as:

• PRP
• Focal retinal laser
• Laser retinopexy
• YAG capsulotomy

do not expose the fetus to ionizing radiation and can be performed when clinically required.

⸻

Surgery During Pregnancy

Urgent sight-saving ocular surgery should:

Not be withheld solely because the patient is pregnant.

When possible:

• Coordinate with obstetrics
• Prefer local/regional anesthesia
• Minimize unnecessary medications
• Consider gestational age and positioning

⸻

Preeclampsia Treatment

Ophthalmic manifestations improve primarily by treating the:

Systemic obstetric disease

Management includes:

• Maternal stabilization
• Blood pressure control
• Seizure prophylaxis when indicated
• Delivery according to obstetric criteria

The ophthalmologist’s role is often:

• Recognition
• Documentation
• Exclusion of competing causes of visual loss

⸻

Follow-Up

Follow-up depends on the condition.

Urgent evaluation is required for:

• Sudden visual loss
• New field defect
• Diplopia
• Severe headache
• Seizure
• New flashes/floaters
• Hypertension with visual symptoms

⸻

Patient Education

Pregnant patients should seek urgent medical assessment for:

• New persistent blurred vision
• Scintillating or missing areas of vision
• Sudden visual loss
• Diplopia
• Severe headache
• Neurologic symptoms
• Seizure

These symptoms should not automatically be attributed to normal pregnancy.

⸻

Prognosis

Most physiologic pregnancy-related ocular changes resolve:

After delivery

Preeclampsia-associated:

• Retinal vasospasm
• Choroidal abnormalities
• Serous retinal detachment
• PRES

often improve markedly after systemic stabilization and delivery.

⸻

Diabetic Retinopathy Prognosis

Pregnancy-related worsening may partly regress postpartum, but:

• Permanent progression can occur
• PDR and DME require continued surveillance

⸻

CSCR Prognosis

Pregnancy-associated CSCR usually:

• Resolves spontaneously
• Has good visual prognosis

but may recur:

• In subsequent pregnancies
• Outside pregnancy

⸻

Complications

Potential ocular and neurologic complications include:

• Permanent retinal ischemia
• Vitreous hemorrhage
• Tractional retinal detachment
• Neovascular glaucoma
• Optic neuropathy
• Cortical blindness
• Stroke
• Persistent visual field loss

⸻

Ophthalmology Pearls

• Pregnancy causes reversible refractive, corneal, and IOP changes; permanent spectacle or refractive surgery decisions are best deferred until postpartum stability.
• New visual symptoms in a pregnant patient can be the first clue to preeclampsia, eclampsia, PRES, retinal vascular disease, or pituitary apoplexy.
• Preeclampsia no longer requires proteinuria if hypertension is accompanied by other maternal end-organ dysfunction, including visual or cerebral symptoms.
• Preeclampsia may produce hypertensive retinopathy, choroidal ischemia, serous retinal detachment, and PRES.
• Bilateral serous retinal detachment in preeclampsia/HELLP usually resolves after maternal stabilization and delivery.
• PRES commonly causes headache, seizures, altered mental status, and cortical visual loss, with parieto-occipital vasogenic edema on MRI.
• Pregnancy can significantly accelerate preexisting diabetic retinopathy, especially when disease is already advanced at conception.
• Gestational diabetes itself does not cause diabetic retinopathy during the pregnancy, but suspected preexisting diabetes warrants retinal evaluation.
• Perform diabetic retinal examination before conception or early in the first trimester and increase surveillance according to baseline retinopathy severity.
• PRP remains the preferred treatment for proliferative diabetic retinopathy during pregnancy.
• Diabetic retinopathy alone is not an indication for cesarean delivery; mode of delivery should usually be based on obstetric factors.
• Intravitreal anti-VEGF is generally avoided when effective alternatives exist because pregnancy safety data are limited and VEGF is important in fetal/placental development.
• Pregnancy-associated CSCR usually occurs in late pregnancy and often resolves postpartum.
• Pituitary apoplexy is an endocrine and neuro-ophthalmic emergency presenting with sudden headache, visual loss, field defects, and/or ophthalmoplegia.
• Sheehan syndrome is postpartum ischemic pituitary necrosis after severe hemorrhage/hypotension, not simply pituitary apoplexy.
• OCT and OCTA are useful noninvasive tests during pregnancy; fluorescein and ICG angiography are generally reserved for cases in which they are clinically necessary.
• MRI without gadolinium is preferred for many neuro-ophthalmic indications; gadolinium is avoided unless essential.
• For topical ophthalmic drugs, use the lowest effective dose and punctal occlusion to reduce systemic exposure.
• Urgent sight- or life-saving ophthalmic treatment should not be delayed solely because of pregnancy.

Ophthalmology – Posterior Vitreous Detachment

Basics

Description

Posterior vitreous detachment (PVD) is separation of the posterior cortical vitreous from the internal limiting membrane (ILM) of the retina.

PVD is a normal age-related process in most people, but the acute separation can exert traction on the retina and occasionally produce:

• Retinal tear
• Vitreous hemorrhage
• Rhegmatogenous retinal detachment

Modern OCT shows that PVD usually develops gradually through stages of:

Perifoveal vitreous separation → persistent vitreofoveal attachment → release from the macula → eventual vitreopapillary separation

An uncomplicated PVD itself generally requires:

No treatment

but an acute symptomatic PVD requires a careful peripheral retinal examination to exclude a retinal break.

Clinical Importance

The most important question in a patient with new:

• Flashes
• Floaters

is not merely whether a PVD is present, but:

Has the PVD produced a retinal tear?

The major red flags are:

• Vitreous hemorrhage
• Shafer sign / tobacco dust
• Retinal or disc hemorrhage
• New field defect
• Reduced vision
• High-risk peripheral retinal pathology

Epidemiology

PVD becomes progressively more common with age.

It typically occurs:

• After middle age
• Earlier in myopic eyes

It may occur much earlier with:

• High myopia
• Trauma
• Intraocular inflammation
• Cataract surgery
• Hereditary vitreoretinopathies

Risk Factors for Earlier PVD

Important factors include:

• Increasing age
• Axial myopia
• Cataract surgery
• Aphakia
• Ocular trauma
• Intraocular inflammation
• Previous vitreoretinal surgery
• Hereditary connective-tissue disorders

High Myopia

Myopic eyes tend to undergo:

• Earlier vitreous liquefaction
• Earlier PVD

They also have an increased risk of:

• Lattice degeneration
• Retinal tears
• Rhegmatogenous retinal detachment

Hereditary Vitreoretinopathies

Earlier or abnormal vitreous separation may occur in:

• Stickler syndrome
• Marfan syndrome
• Other collagen disorders

Stickler syndrome is particularly important because of its high risk of:

Retinal detachment

Cataract Surgery

PVD becomes more common after cataract extraction.

Risk of retinal complications is particularly relevant in:

• Highly myopic patients
• Younger pseudophakic patients
• Eyes with lattice degeneration
• Surgery complicated by posterior capsule rupture or vitreous loss

Vitreous Anatomy

The vitreous is firmly attached at several sites, particularly:

• Vitreous base
• Optic nerve head
• Macula/fovea
• Retinal vessels

The vitreous base remains the strongest physiologic attachment and does not normally separate completely even after a conventional PVD.

Pathophysiology

Two processes are required for normal PVD:

1. Vitreous liquefaction (synchysis)
2. Weakening of vitreoretinal adhesion

When these processes occur in balance:

• Vitreous separates cleanly

When liquefaction occurs without adequate release of vitreoretinal adhesion:

• Abnormal traction may develop

leading to vitreomacular or retinal complications.

Vitreous Liquefaction

With age:

• Hyaluronic acid–collagen organization deteriorates
• Fluid-filled lacunae develop
• Collagen fibrils aggregate into visible strands

These condensations may be perceived as:

Floaters

Evolution of PVD

Posterior vitreous separation often begins:

Perifoveally

while attachment persists at the:

• Fovea
• Optic disc

With progression:

• Vitreous releases from the fovea
• Then eventually from the optic nerve head

Vitreomacular Adhesion

If the posterior vitreous has separated around the macula but remains attached at the fovea without retinal distortion, this is:

Vitreomacular adhesion (VMA)

VMA is frequently physiologic and asymptomatic.

Vitreomacular Traction

If persistent vitreofoveal adhesion produces retinal distortion, the condition becomes:

Vitreomacular traction (VMT)

Possible effects include:

• Foveal cysts
• Metamorphopsia
• Reduced vision
• Impending or full-thickness macular hole

Acute Symptomatic PVD

An acute PVD occurs when posterior vitreous separation progresses sufficiently to produce sudden symptoms.

Typical symptoms are:

• Photopsias
• New floaters

The onset may be abrupt.

Photopsias

Flashes occur because of:

Mechanical vitreoretinal traction stimulating the retina

They are often:

• Brief
• Peripheral
• Arc-like or lightning-like
• More noticeable in darkness

Floaters

Floaters may result from:

• Condensed vitreous collagen
• Weiss ring
• Pigment
• Red blood cells

Patients may describe:

• Spots
• Cobwebs
• Threads
• Rings
• Clouds

A sudden shower of numerous small floaters is especially concerning for:

Vitreous hemorrhage or pigment from a retinal tear

Weiss Ring

A Weiss ring is a circular or incomplete opacity representing tissue detached from around the optic nerve head.

It indicates:

Vitreopapillary separation

and strongly supports the diagnosis of an advanced PVD.

However, a visible Weiss ring does not absolutely prove that all posterior and peripheral vitreoretinal adhesions have released.

Symptoms Suggestive of Retinal Detachment

Urgent warning symptoms include:

• New curtain or shadow
• Peripheral field loss
• Sudden reduction in vision
• Rapid increase in floaters
• Persistent or increasing photopsias

These require:

Immediate retinal evaluation

Diagnosis

Diagnosis relies primarily on:

• History
• Slit-lamp vitreous examination
• Dilated peripheral retinal examination

The critical goal is to exclude:

Retinal tear or retinal detachment

Slit-Lamp Examination

Using a high-powered lens, look for:

• Weiss ring
• Vitreous pigment
• Vitreous hemorrhage
• Posterior hyaloid
• Retinal hemorrhage

Shafer Sign

Shafer sign is the presence of brown pigment granules in the anterior vitreous.

It is also called:

Tobacco dust

In an acute symptomatic PVD, Shafer sign is highly suspicious for:

A retinal break

until proven otherwise.

Vitreous Hemorrhage

Vitreous hemorrhage accompanying acute PVD markedly increases the likelihood of:

• Retinal tear
• Retinal detachment

A retinal tear should be assumed possible until a careful peripheral retinal examination has been completed.

Dilated Fundus Examination

The examination should include:

Indirect ophthalmoscopy with scleral depression whenever possible

because retinal tears may occur:

• Very anteriorly
• Near the vitreous base

and may be missed with posterior pole examination alone.

Scleral Depression

Scleral depression improves visualization of:

• Ora serrata
• Vitreous base
• Horseshoe tears
• Small peripheral retinal breaks

It remains an important part of acute symptomatic PVD evaluation.

Wide-Field Imaging

Ultra-widefield photography may document:

• Peripheral retinal lesions
• Hemorrhage
• Some retinal tears

but:

It does not reliably replace careful indirect ophthalmoscopy with scleral depression when a retinal tear is suspected.

Optical Coherence Tomography

OCT is particularly useful for assessing:

• Partial PVD
• Vitreomacular adhesion
• Vitreomacular traction
• Macular hole
• Epiretinal membrane

It can show the:

Posterior hyaloid face

over the macula.

Important OCT Limitation

Macular OCT does:

Not exclude a peripheral retinal tear.

A normal macular OCT does not eliminate the need for peripheral retinal examination in an acute symptomatic PVD.

B-Scan Ultrasonography

B-scan is particularly useful when the retina cannot be adequately visualized because of:

• Dense vitreous hemorrhage
• Cataract
• Corneal opacity
• Other media opacity

It may demonstrate:

• Mobile detached posterior hyaloid
• Retinal detachment
• Vitreous hemorrhage

PVD vs Retinal Detachment on B-Scan

A detached posterior hyaloid is generally:

• Thin
• Highly mobile
• Less reflective
• Not attached to the optic disc in the same way as detached retina

Retinal detachment is typically:

• More reflective
• Less mobile
• Tethered at the optic disc

Clinical correlation remains essential.

Differential Diagnosis of Flashes and Floaters

Important differentials include:

• Retinal tear
• Rhegmatogenous retinal detachment
• Vitreous hemorrhage
• Migraine aura
• Vitritis
• Ocular trauma
• Posterior uveitis
• Vitreomacular traction
• Intraocular foreign body in appropriate circumstances

Retinal Tear

The most important retinal tear associated with acute PVD is a:

Horseshoe / flap tear

It develops when persistent focal vitreoretinal adhesion pulls strongly enough to tear the retina.

Common locations include the:

• Superior temporal retina
• Other areas of lattice degeneration or strong adhesion

Risk of Retinal Tear

Among patients with acute symptomatic PVD, a retinal tear is found in approximately:

8–15% at the initial examination

depending on the population studied.

Risk is considerably higher when:

• Vitreous hemorrhage is present
• Shafer sign is positive
• Lattice degeneration is present
• Patient is highly myopic
• There is a previous retinal tear/detachment

Delayed Retinal Tears

A normal initial examination does not reduce the future risk to zero.

A small proportion of patients develop:

Delayed retinal breaks

over the subsequent weeks or months as vitreous separation progresses.

This is why appropriate follow-up and patient education are important.

High-Risk Features for Delayed Breaks

Closer surveillance is appropriate with:

• Vitreous hemorrhage
• Retinal hemorrhage
• Shafer sign
• Lattice degeneration
• High myopia
• Previous retinal tear
• Previous retinal detachment
• Retinal tear/detachment in the fellow eye
• Recent intraocular surgery
• Trauma

Associated Macular Conditions

Partial PVD can be associated with:

• Vitreomacular adhesion
• Vitreomacular traction
• Epiretinal membrane
• Full-thickness macular hole
• Lamellar macular hole
• Myopic traction maculopathy
• Vitreopapillary traction

Epiretinal Membrane

An anomalous PVD may leave residual cortical vitreous on the retinal surface.

This can facilitate:

• Cellular proliferation
• Epiretinal membrane formation

Macular Hole

Persistent focal vitreofoveal traction can contribute to:

Full-thickness macular hole formation

Spontaneous release of traction can occasionally arrest or reverse very early tractional changes.

Vitreopapillary Traction

Persistent adhesion to the optic nerve may cause:

• Optic disc elevation
• Peripapillary hemorrhage
• Apparent disc swelling

This can occasionally mimic:

• Papilledema
• Other optic disc edema

OCT can help demonstrate the tractional mechanism.

Treatment

Uncomplicated PVD

An uncomplicated PVD requires:

No medical or surgical treatment

The key intervention is:

• Retinal examination
• Appropriate follow-up
• Patient education

Activity Restriction

Routine restriction of:

• Exercise
• Bending
• Lifting
• Normal daily activity

after uncomplicated PVD has not been shown to prevent retinal tears.

Reasonable individualized caution may be advised in selected high-risk cases, but strict activity restriction is not standard treatment.

Retinal Tear Treatment

A retinal tear at significant risk of progression to detachment is treated with:

• Laser retinopexy
• Cryopexy in selected cases

The treatment creates a chorioretinal adhesion around the break.

Symptomatic Horseshoe Tear

An acute symptomatic horseshoe tear associated with persistent vitreoretinal traction generally requires:

Prompt retinopexy

because of its substantial risk of progressing to retinal detachment.

Operculated Retinal Hole

Not every operculated hole requires treatment.

Management depends on:

• Symptoms
• Residual traction
• Subretinal fluid
• Location
• Other retinal risk factors

Rhegmatogenous Retinal Detachment

If retinal detachment is present, urgent vitreoretinal management may involve:

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

depending on:

• Break configuration
• Lens status
• Extent of detachment
• Macular status

Persistent Floaters

Floaters often become less intrusive over:

Weeks to months

because of:

• Neuroadaptation
• Movement of opacities away from the visual axis
• Changes in vitreous configuration

Vitrectomy for Floaters

Pars plana vitrectomy can remove severe symptomatic vitreous opacities.

However, because an otherwise benign symptom is being treated, risks must be carefully weighed, including:

• Cataract
• Retinal tear
• Retinal detachment
• Endophthalmitis
• Hypotony

It is reserved for:

Carefully selected patients with persistent, functionally disabling floaters.

YAG Vitreolysis

Nd:YAG laser vitreolysis has been used for selected vitreous floaters.

However:

• Evidence for long-term benefit is limited
• Not all floaters are suitable
• Retinal and lens complications are possible

It is not routine treatment for uncomplicated acute PVD.

Follow-Up

Patients with an acute symptomatic PVD and no tear on initial examination commonly undergo:

Repeat dilated retinal examination within several weeks

often around:

4–6 weeks

depending on clinical risk.

Earlier Follow-Up

Earlier or additional examination is warranted with:

• Vitreous hemorrhage
• Shafer sign
• Retinal hemorrhage
• Lattice degeneration
• High myopia
• Prior retinal tear/detachment
• Poor view of peripheral retina

Return Precautions

Regardless of planned follow-up, patients should return immediately for:

• Sudden increase in floaters
• New or increasing flashes
• Curtain or shadow
• Loss of peripheral vision
• Sudden reduction in visual acuity

Fellow Eye

PVD often eventually develops in the fellow eye.

Patients with a retinal tear or detachment in one eye have increased risk of:

• Peripheral retinal pathology
• Retinal tear
• Retinal detachment

in the fellow eye.

Patient Education

Patients should understand that:

• PVD itself is usually benign
• Flashes usually diminish as traction releases
• Floaters often become less noticeable
• Retinal tears can occur during the evolution of PVD

The danger signs of retinal detachment should be explained clearly.

Prognosis

For uncomplicated PVD:

Prognosis is excellent.

Photopsias generally diminish as vitreoretinal traction resolves.

Floaters may persist but often become much less noticeable.

Prognosis After Retinal Tear

When a retinal tear is recognized and treated before retinal detachment occurs:

Visual prognosis is generally excellent.

Delayed detection increases the risk of:

• Rhegmatogenous retinal detachment
• Macular involvement
• Permanent visual loss

Complications

Important complications include:

• Retinal tear
• Rhegmatogenous retinal detachment
• Vitreous hemorrhage
• Retinal hemorrhage
• Epiretinal membrane
• Vitreomacular traction
• Macular hole
• Vitreopapillary traction

Ophthalmology Pearls

• PVD is separation of the posterior cortical vitreous from the retinal ILM and becomes increasingly common with age.
• The classic acute symptoms are new flashes and floaters.
• The most important question in an acute symptomatic PVD is: Is there a retinal tear?
• A Weiss ring indicates vitreopapillary separation and strongly supports an advanced PVD, but does not guarantee that every peripheral vitreoretinal adhesion has released.
• Shafer sign (“tobacco dust”) is highly suspicious for a retinal tear.
• Vitreous hemorrhage dramatically increases concern for an associated retinal break.
• Acute symptomatic PVD should be examined with a dilated peripheral retinal examination, ideally including scleral depression.
• Macular OCT is excellent for detecting partial PVD and vitreomacular traction but cannot exclude a peripheral retinal tear.
• B-scan ultrasonography is important when vitreous hemorrhage or other media opacity prevents adequate retinal visualization.
• Approximately 8–15% of symptomatic acute PVDs have a retinal tear at initial examination, with additional delayed tears occurring in a smaller proportion.
• A normal first examination does not completely eliminate later risk; many patients are re-examined at approximately 4–6 weeks, with earlier/more frequent review for high-risk findings.
• New curtain, field loss, sudden visual decline, increased flashes, or a shower of floaters requires urgent reassessment.
• Uncomplicated PVD requires no treatment.
• Acute symptomatic horseshoe tears generally require prompt laser retinopexy or cryopexy to prevent retinal detachment.
• Persistent symptomatic floaters usually improve with time; vitrectomy is reserved for carefully selected, severely affected patients because it carries meaningful surgical risk.

Ophthalmology – Peripapillary Staphyloma

Basics

Description

Peripapillary staphyloma is a rare congenital optic nerve anomaly characterized by a deep excavation of the posterior fundus surrounding an otherwise relatively normal optic disc.

The optic disc lies at the bottom of the excavation and may appear:

• Normal
• Mildly pale
• Occasionally tilted or distorted by the surrounding ectasia

The surrounding:

• Retina
• Retinal pigment epithelium
• Choroid

often show atrophic or pigmentary changes.

This congenital lesion should be distinguished from the much more common acquired posterior staphyloma of pathologic myopia.

⸻

Important Terminology

The older term posterior staphyloma can be confusing.

In this congenital optic-disc context, the preferred descriptive term is:

Peripapillary staphyloma

This is a developmental optic nerve anomaly.

By contrast, myopic posterior staphyloma is an acquired outward bulging of the posterior eyewall in pathologic myopia.

⸻

Epidemiology

Peripapillary staphyloma is:

• Very rare
• Usually unilateral
• Congenital

It may occasionally be:

• Bilateral
• Associated with another congenital ocular anomaly in the fellow eye

⸻

Genetics

Most cases are:

Sporadic

A consistent Mendelian inheritance pattern has not been established.

⸻

Embryology and Pathogenesis

The exact mechanism is uncertain.

A developmental defect of the posterior globe is thought to occur after formation of the optic disc.

The result is:

Localized ectasia of the scleral and choroidal tissues surrounding the optic nerve

while the optic disc itself remains relatively normally formed.

⸻

Key Anatomical Feature

The defining feature is:

A normal or near-normal optic disc situated at the base of a broad, deep peripapillary excavation.

This distinguishes peripapillary staphyloma from:

• Morning glory disc anomaly
• Optic disc coloboma

where the disc itself is directly malformed.

⸻

Clinical Presentation

Patients may present with:

• Reduced unilateral visual acuity
• Strabismus
• Nystagmus if bilateral/severe
• Abnormal head posture
• Failed childhood vision screening

Some patients have surprisingly good vision despite striking anatomy.

⸻

Visual Acuity

Visual acuity is highly variable.

It may range from:

• Near-normal vision
• Moderate visual impairment
• Severe visual loss

Reduced vision may result from:

• Congenital retinal/optic nerve dysfunction
• Macular involvement
• Refractive error
• Amblyopia
• Retinal detachment

⸻

Refractive Error

Unlike myopic posterior staphyloma, the affected eye may be:

• Emmetropic
• Mildly myopic
• Occasionally hyperopic

Therefore:

High myopia is not required.

⸻

Visual Field

A visual field defect may include:

• Central scotoma
• Cecocentral scotoma
• Other defects corresponding to abnormal posterior pole anatomy

Formal field testing is useful when age and visual function permit.

⸻

Fundus Examination

Typical findings include:

• Deep bowl-shaped excavation surrounding optic nerve
• Optic disc at the bottom of the excavation
• Peripapillary chorioretinal atrophy
• Pigmentary changes at the margin
• Relatively normal retinal vessels emerging from the disc

Unlike morning glory anomaly, there is generally no:

• Central glial tuft
• Markedly abnormal radial vascular pattern

⸻

Optic Disc

The optic disc itself may be:

• Normal in appearance
• Mildly pale
• Occasionally temporally pale

A normal-appearing disc within the excavation is diagnostically helpful.

⸻

Contractile Movement

Rare cases have demonstrated:

Spontaneous contractile movement of the staphylomatous excavation

The mechanism is uncertain but may involve:

• Smooth-muscle-like or contractile tissue
• Changes in intraocular pressure or choroidal circulation

This phenomenon is unusual and not required for diagnosis.

⸻

Associated Ocular Findings

Possible associations include:

• Strabismus
• Nystagmus
• Amblyopia
• Abnormal head posture
• Fellow-eye congenital anomalies

The contralateral eye should always be examined carefully.

⸻

Retinal Detachment

The most important acquired complication is:

Retinal detachment

Detachment may be:

• Rhegmatogenous
• Tractional
• Serous in selected congenital excavation anomalies

Risk is related to abnormal posterior pole anatomy.

⸻

Macular Involvement

Visual potential depends heavily on:

• Foveal development
• Macular position relative to the excavation
• Secondary retinal abnormalities

OCT is useful when the macula can be imaged.

⸻

Diagnosis

Diagnosis is usually clinical based on:

• Characteristic fundus appearance
• Optic disc located at the base of a broad surrounding excavation
• Absence of classic features of morning glory disc anomaly or optic disc coloboma

⸻

Optical Coherence Tomography

OCT can document:

• Depth and contour of the excavation
• Retinal layer architecture
• Macular involvement
• Peripapillary atrophy
• Associated schisis or detachment

Enhanced-depth imaging or swept-source OCT may further demonstrate:

• Choroid
• Scleral contour

⸻

B-Scan Ultrasonography

B-scan may be useful to assess:

• Posterior globe contour
• Depth of excavation
• Associated retinal detachment

It can help distinguish a true posterior wall ectasia from optic-disc-only excavation.

⸻

Fundus Photography

Wide-field or standard fundus photography is helpful for:

• Baseline documentation
• Monitoring structural change
• Demonstrating the relationship between optic disc and excavation

⸻

OCT-A / Angiography

Not routinely required.

May be useful if there is concern for:

• Secondary choroidal neovascularization
• Vascular abnormality
• Associated retinal complication

⸻

Differential Diagnosis

The major differentials are:

• Morning glory disc anomaly
• Optic disc coloboma
• Myopic posterior staphyloma
• Optic disc pit
• Tilted disc syndrome

⸻

Peripapillary Staphyloma vs Morning Glory Disc Anomaly

Peripapillary Staphyloma

• Deep excavation surrounding the optic disc
• Disc itself relatively normal
• No central glial tuft
• Retinal vessels not classically arranged radially
• Usually no pigment ring encircling a malformed disc

Morning Glory Disc Anomaly

• Funnel-shaped excavation incorporating the disc
• Enlarged anomalous disc
• Central white glial tuft
• Radial spoke-like vessels
• Peripapillary pigment ring
• Associated with CNS and vascular anomalies, including moyamoya and basal encephalocele

This distinction is important because morning glory anomaly has much stronger systemic associations.

⸻

Peripapillary Staphyloma vs Optic Disc Coloboma

Peripapillary Staphyloma

• Excavation surrounds the disc
• Disc relatively preserved
• No typical inferonasal embryonic fissure defect

Optic Disc Coloboma

• Excavation involves the optic disc itself
• Usually inferior or inferonasal
• May extend into adjacent choroid/retina
• Often associated with other colobomatous defects

⸻

Peripapillary Staphyloma vs Myopic Posterior Staphyloma

Congenital Peripapillary Staphyloma

• Usually unilateral
• Congenital
• May occur without high myopia
• Optic-disc-centered excavation

Myopic Posterior Staphyloma

• Associated with pathologic axial myopia
• Acquired/progressive
• Outpouching of posterior eyewall
• May involve macula or other posterior pole regions
• Associated with myopic maculopathy, traction maculopathy, and CNV

⸻

Treatment

There is:

No treatment that corrects the congenital staphylomatous excavation itself.

Management focuses on:

• Maximizing vision
• Treating amblyopia
• Correcting refractive error
• Managing strabismus
• Monitoring for retinal detachment

⸻

Refractive Correction

Perform:

Cycloplegic refraction

particularly in children.

Correct:

• Myopia
• Hyperopia
• Astigmatism
• Anisometropia

to optimize visual potential.

⸻

Amblyopia Therapy

If unilateral reduced vision is partly amblyopic, treatment may include:

• Spectacle correction
• Patching of the better eye
• Atropine penalization in selected cases

The response may be limited by underlying congenital retinal or optic nerve abnormalities.

⸻

Strabismus

Strabismus may develop because of reduced vision.

Management may include:

• Amblyopia treatment first
• Prism in selected cases
• Strabismus surgery when appropriate

⸻

Retinal Detachment

Retinal detachment requires:

Prompt vitreoretinal evaluation

Treatment depends on the mechanism and may include:

• Vitrectomy
• Laser photocoagulation
• Tamponade
• Other retinal surgical techniques

Surgery can be challenging because of abnormal posterior anatomy.

⸻

Protective Eyewear

If one eye has substantially reduced vision:

Impact-resistant protective eyewear is recommended

to protect the better-seeing eye.

⸻

Low-Vision Rehabilitation

For significant bilateral impairment, consider:

• Low-vision evaluation
• Magnification
• Educational accommodations
• Orientation and mobility support when necessary

⸻

Follow-Up

Follow-up should include:

• Visual acuity
• Refraction
• Amblyopia assessment
• Alignment
• Dilated retinal examination
• OCT when useful

Frequency depends on:

• Age
• Visual function
• Retinal status
• Presence of complications

⸻

Retinal Surveillance

Patients should be monitored for:

• New retinal breaks
• Retinal detachment
• Macular changes

Urgent assessment is warranted for:

• New flashes
• Floaters
• Curtain or shadow
• Sudden visual decline

⸻

Pediatric Considerations

In children, the priority is to maximize visual development.

Evaluate promptly for:

• Refractive error
• Anisometropia
• Strabismus
• Amblyopia

Failure to treat a superimposed amblyopic component may unnecessarily reduce final visual acuity.

⸻

Prognosis

Visual prognosis is highly variable.

Some patients retain:

• Good central vision

while others have substantial congenital visual impairment.

Outcome depends on:

• Macular anatomy
• Optic nerve function
• Degree of amblyopia
• Refractive error
• Development of retinal detachment

⸻

Complications

The major complications are:

• Amblyopia
• Strabismus
• Retinal detachment
• Permanent visual loss

⸻

Ophthalmology Pearls

• Peripapillary staphyloma is a congenital deep excavation surrounding a relatively normal optic disc.
• The optic disc lies at the bottom of the excavation, rather than being the malformed excavated structure itself.
• The lesion is usually unilateral and sporadic.
• High myopia is not required, distinguishing it from acquired myopic posterior staphyloma.
• The most important differentials are morning glory disc anomaly and optic disc coloboma.
• Morning glory anomaly has a central glial tuft, radial vessels, and funnel-shaped anomalous disc, while peripapillary staphyloma usually does not.
• Optic disc coloboma typically involves the disc itself, often inferiorly.
• OCT and B-scan can help define the posterior globe excavation and detect associated retinal pathology.
• There is no treatment for the congenital excavation itself.
• Management should maximize visual potential with refractive correction and amblyopia therapy.
• Patients require surveillance for retinal detachment, the major sight-threatening acquired complication.
• In unilateral disease with poor vision, recommend protective eyewear for the better eye.

Ophthalmology – Posterior Polymorphous Corneal Dystrophy

Basics

Description

Posterior polymorphous corneal dystrophy (PPCD/PPMD) is an inherited disorder of the corneal endothelium and Descemet membrane, usually bilateral but often markedly asymmetric.

The hallmark abnormality is transformation of corneal endothelial cells toward an:

Epithelial-like phenotype

This may produce:

• Vesicular posterior corneal lesions
• Band-like or geographic opacities
• Thickened/abnormal Descemet membrane
• Peripheral anterior synechiae
• Secondary glaucoma
• Corneal edema in more severe disease

Most affected patients remain:

Asymptomatic throughout life.

Clinical Importance

Although PPCD is usually mild, severe disease may cause:

• Progressive endothelial failure
• Stromal and epithelial edema
• Reduced visual acuity
• Secondary glaucoma
• Iridocorneal adhesions

In children, dense corneal edema or opacity can additionally cause:

Deprivation amblyopia

Epidemiology

PPCD is rare.

The exact:

• Incidence
• Prevalence

are unknown because many patients are asymptomatic and never diagnosed.

Inheritance

PPCD is most commonly inherited in an:

Autosomal dominant

pattern with variable expressivity.

Disease severity may differ substantially:

• Between family members
• Between the two eyes of the same patient

Genetics

Important modern genetic associations include:

• ZEB1
• OVOL2 regulatory variants
• GRHL2 regulatory variants

Older classifications described a COL8A2-associated “PPCD2” phenotype, but current molecular classification has evolved, and COL8A2 is more strongly associated with certain endothelial dystrophy phenotypes such as early-onset Fuchs disease rather than being a major cause of typical PPCD.

Genetic testing is most useful when:

• Disease is familial
• Presentation is early or severe
• Diagnosis is uncertain
• Counseling is desired

ZEB1-Associated PPCD

ZEB1 is an important cause of PPCD.

ZEB1 normally helps maintain:

Corneal endothelial identity

Loss of normal ZEB1 activity promotes:

• Endothelial-to-epithelial transformation
• Abnormal multilayering
• Epithelial marker expression

This explains much of the characteristic histology of PPCD.

Pathophysiology

Normal corneal endothelium consists of a:

• Single layer
• Nonregenerating
• Hexagonal endothelial cells

In PPCD, endothelial cells may acquire epithelial-like characteristics, including:

• Cellular proliferation
• Multilayering
• Desmosomes
• Cytokeratin expression
• Microvilli

These abnormal cells may migrate onto:

• Trabecular meshwork
• Peripheral iris

leading to:

• Peripheral anterior synechiae
• Angle obstruction
• Secondary glaucoma

Descemet Membrane Abnormalities

Descemet membrane may show:

• Irregular thickening
• Abnormal posterior collagenous material
• Focal excrescences
• Vesicular or band-like changes

These correspond clinically to the classic posterior corneal lesions.

Clinical Presentation

Most patients are:

Asymptomatic

and diagnosed incidentally.

Symptomatic patients may report:

• Blurred vision
• Glare
• Foreign-body sensation
• Photophobia
• Fluctuating vision

Symptoms usually result from:

• Corneal edema
• Irregular astigmatism
• Secondary glaucoma

Laterality

PPCD is generally:

Bilateral

but can be strikingly asymmetric.

Occasionally one eye appears clinically normal.

Slit-Lamp Findings

Classic posterior corneal findings include:

• Vesicles
• Band-like lesions
• Geographic opacities
• “Railroad-track” lesions
• Abnormal thickening of Descemet membrane

Vesicular Lesions

The classic lesion is a:

Small posterior corneal vesicle

which may be:

• Solitary
• Grouped
• Surrounded by a gray halo

They arise at the level of:

• Endothelium
• Descemet membrane

Band Lesions

Linear or curvilinear lesions may appear as:

Parallel tracks

sometimes described as:

• Railroad tracks
• Snail-track-like posterior opacities

These reflect broader areas of abnormal endothelium and Descemet membrane.

Geographic Lesions

Some patients develop:

• Irregular
• Geographic
• Sheet-like posterior corneal opacities

These may be associated with more extensive endothelial dysfunction.

Corneal Edema

Most patients do not develop significant edema.

In advanced disease:

• Endothelial pump failure

can produce:

• Stromal edema
• Epithelial edema
• Bullous keratopathy
• Subepithelial fibrosis

Pediatric Disease

Rare severe cases may present in infancy or childhood with:

• Corneal edema
• Corneal haze
• Reduced vision

This may cause:

Form-deprivation amblyopia

and requires early visual rehabilitation.

Iris and Angle Findings

Abnormal endothelial-like cells may extend across the angle.

Findings may include:

• Peripheral anterior synechiae
• Iridocorneal adhesions
• Distorted pupil in severe cases
• Abnormal angle membranes

These features increase the risk of:

Secondary glaucoma

Glaucoma

Glaucoma is the most important noncorneal complication.

Possible mechanisms include:

• Endothelial-like membrane extending over trabecular meshwork
• PAS formation
• Developmental angle abnormalities
• Open-angle outflow obstruction

Glaucoma can therefore occur with:

• Open angles
• Synechially closed angles
• Mixed mechanisms

Intraocular Pressure

IOP should be measured in all patients because glaucoma may be:

• Asymptomatic
• Progressive
• Disproportionate to the degree of corneal disease

Optic Nerve Assessment

Evaluate:

• Cup-to-disc ratio
• Neuroretinal rim
• RNFL OCT
• Macular GCIPL/GCC
• Visual fields

when age and visual function permit.

Gonioscopy

Gonioscopy is important to assess for:

• PAS
• Abnormal endothelial membrane
• Angle closure
• Developmental angle abnormalities

This helps determine the glaucoma mechanism.

Pachymetry

Central corneal thickness may increase with:

• Endothelial dysfunction
• Corneal edema

Serial pachymetry can help monitor:

• Progression
• Response to treatment

but is not specific for PPCD.

Specular Microscopy

Specular microscopy may show:

• Abnormal endothelial morphology
• Multilayered or vesicular lesions
• Reduced normal hexagonal pattern
• Highly irregular endothelial mosaic

It can help distinguish PPCD from other endothelial dystrophies.

Confocal Microscopy

In vivo confocal microscopy may demonstrate:

• Abnormal endothelial morphology
• Epithelial-like cells
• Vesicular lesions
• Multilayered cell patterns

It can be useful when:

• Slit-lamp visualization is poor
• Corneal edema obscures the posterior cornea

Anterior Segment OCT

AS-OCT may help document:

• Descemet abnormalities
• Posterior corneal lesions
• Corneal thickness
• Peripheral adhesions

but diagnosis is usually clinical.

Corneal Tomography

Corneal topography/tomography may be useful if there is:

• Significant astigmatism
• Suspected keratoconus
• Irregular corneal shape

Associated Corneal Disorders

PPCD has occasionally been reported with:

• Keratoconus
• Keratoglobus
• Other ectatic corneal disorders

Some ZEB1-associated phenotypes may have:

• Steeper corneas
• Abnormal corneal biomechanics

but these associations are variable.

Diagnosis

Diagnosis is usually based on:

• Characteristic slit-lamp appearance
• Bilaterality/asymmetry
• Family history
• Gonioscopy
• Specular or confocal microscopy when needed

Genetic Testing

Genetic testing may support the diagnosis in selected patients.

Consider especially when there is:

• Strong autosomal dominant family history
• Severe childhood disease
• Atypical presentation
• Need for family counseling

Differential Diagnosis

Important differentials include:

• Iridocorneal endothelial syndrome
• Fuchs endothelial corneal dystrophy
• Congenital hereditary endothelial dystrophy
• Descemet membrane tears
• Birth trauma
• Corneal edema from glaucoma
• Other posterior corneal dystrophies

PPCD vs ICE Syndrome

This is one of the most important distinctions.

PPCD

Usually:

• Bilateral
• Familial
• Younger onset
• Often relatively stable
• Endothelial cells have epithelial-like characteristics

ICE Syndrome

Typically:

• Unilateral
• Sporadic
• Adult onset
• Progressive
• More common in women
• Associated with:
• Corectopia
• Iris atrophy
• PAS
• Secondary glaucoma

PPCD vs Fuchs Endothelial Corneal Dystrophy

PPCD

• Vesicles/bands
• Often younger onset
• Epithelialized endothelial cells
• PAS may occur
• Autosomal dominant families possible

Fuchs

• Central guttae
• Progressive endothelial loss
• Central-to-peripheral edema
• Usually later onset
• No characteristic epithelial transformation of endothelium

PPCD vs Congenital Hereditary Endothelial Dystrophy

CHED typically presents with:

• Bilateral diffuse corneal edema
• Corneal clouding from infancy or childhood
• No classic posterior vesicles or railroad-track lesions

Modern CHED is primarily associated with:

SLC4A11

and usually follows an:

Autosomal recessive

inheritance pattern.

PPCD vs Descemet Tears

Descemet tears may occur after:

• Birth trauma
• Congenital glaucoma
• Surgery

They usually appear:

• Linear
• Localized

and lack the typical familial bilateral pattern of PPCD.

Treatment Principles

Most patients require:

Observation only

Treatment is directed toward complications rather than the dystrophy itself.

Mild Disease

If the patient is asymptomatic with:

• Clear cornea
• Normal IOP
• No progressive glaucoma

management consists of:

• Observation
• Periodic corneal examination
• Glaucoma surveillance

Hypertonic Saline

Hypertonic sodium chloride may reduce symptoms from:

• Epithelial edema
• Morning blur

It can be used as:

• Drops
• Ointment

However:

It does not reverse endothelial dysfunction or prevent progression.

Lubrication

Artificial tears may help if there is:

• Surface irritation
• Recurrent epithelial symptoms

Glaucoma Treatment

IOP-lowering therapy may include:

• Prostaglandin analogs
• Beta-blockers
• Carbonic anhydrase inhibitors
• Alpha-2 agonists

Treatment depends on:

• Angle status
• Severity
• Optic nerve damage

Glaucoma Surgery

Surgery may be required when:

• IOP remains uncontrolled
• PAS are extensive
• Glaucomatous progression occurs

Options include:

• Trabeculectomy
• Glaucoma drainage device
• Other glaucoma procedures based on angle anatomy

Angle surgery may have limited success in eyes with significant:

• PAS
• Endothelial membrane overgrowth

Endothelial Keratoplasty

For visually significant endothelial failure:

Endothelial keratoplasty is generally preferred over penetrating keratoplasty when anatomy permits.

Options include:

• DMEK
• DSAEK/DSEK

DMEK

DMEK offers:

• Rapid visual rehabilitation
• Minimal induced astigmatism
• Low rejection risk

However, PPCD can be technically challenging because of:

• Abnormal Descemet membrane
• PAS
• Irregular posterior corneal anatomy

Case selection is important.

DSAEK / DSEK

DSAEK may be preferred in some complex eyes because:

• Tissue is easier to manipulate
• Surgery may be more forgiving when the anterior segment is abnormal

Visual recovery may be slightly less optimal than with DMEK.

Penetrating Keratoplasty

PK is now generally reserved for cases with:

• Significant stromal scarring
• Extensive structural abnormalities
• Failed endothelial keratoplasty
• Anatomy unsuitable for endothelial keratoplasty

Pediatric Surgery

In children with severe corneal edema, early intervention may be needed to prevent:

Irreversible amblyopia

Management should include:

• Corneal surgery when indicated
• Optical correction
• Amblyopia therapy

Amblyopia

Children with asymmetric or bilateral corneal opacity require:

• Cycloplegic refraction
• Spectacle/contact lens correction
• Patching when appropriate
• Close pediatric ophthalmic follow-up

A clear graft alone does not guarantee good visual development.

Follow-Up

Follow-up should assess:

• Visual acuity
• Corneal clarity
• Corneal thickness
• IOP
• Gonioscopy
• Optic nerve
• OCT
• Visual fields when appropriate

Family Screening

Because many cases are autosomal dominant:

First-degree relatives may benefit from slit-lamp examination and IOP screening.

Family screening may reveal:

• Mild vesicular disease
• Previously unrecognized glaucoma

Prognosis

Overall prognosis is:

Excellent in most patients

because disease is often mild or slowly progressive.

Only a minority develop:

• Significant endothelial failure
• Severe glaucoma
• Need for corneal transplantation

Poor Prognostic Features

More severe disease is associated with:

• Early corneal edema
• Extensive PAS
• Secondary glaucoma
• Significant endothelial failure
• Dense stromal scarring

Complications

Potential complications include:

• Secondary glaucoma
• Peripheral anterior synechiae
• Corneal edema
• Bullous keratopathy
• Stromal scarring
• Reduced vision
• Amblyopia in children

Ophthalmology Pearls

• Posterior polymorphous corneal dystrophy is an inherited disorder of Descemet membrane and corneal endothelium, usually bilateral but often asymmetric.
• The classic lesions are posterior corneal vesicles, band-like “railroad-track” lesions, and geographic opacities.
• The fundamental cellular abnormality is epithelial-like transformation of corneal endothelial cells.
• Important modern genetic associations include ZEB1, OVOL2, and GRHL2.
• Most patients are asymptomatic and need only observation.
• Always screen for glaucoma, because abnormal endothelial cells can extend across the angle and produce PAS or trabecular obstruction.
• Gonioscopy is important to identify peripheral anterior synechiae and angle involvement.
• PPCD differs from ICE syndrome because PPCD is usually bilateral and familial, whereas ICE is typically unilateral, sporadic, and progressive.
• PPCD differs from Fuchs dystrophy by its vesicular/band lesions and epithelialized endothelium rather than central guttae.
• Hypertonic saline may improve symptoms from edema but does not correct endothelial failure.
• When corneal decompensation becomes visually significant, DMEK or DSAEK/DSEK is generally preferred over PK when anatomy is suitable.
• In children, severe corneal edema requires early treatment because of the risk of deprivation amblyopia.
• Family members may benefit from screening because PPCD is commonly autosomal dominant with variable expressivity.