Ophthalmology – Sympathetic Ophthalmia

What the Disease Represents

Sympathetic ophthalmia (SO) is a rare, bilateral, diffuse granulomatous panuveitis that develops after:

• Penetrating ocular trauma
• Intraocular surgery
• Occasionally other procedures that disrupt the uveal tissues

The injured or operated eye is traditionally called the:

Exciting/inciting eye

and the fellow eye is called the:

Sympathizing eye

Although only one eye is initially injured, the subsequent autoimmune inflammation typically affects:

Both eyes.

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Why the Fellow Eye Becomes Inflamed

The leading mechanism is an autoimmune response to previously sequestered ocular antigens released after disruption of the:

• Uvea
• Retina
• Choroid

This produces:

T-cell-mediated immune attack against melanocyte- and retinal-associated antigens

in both eyes.

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How Rare It Is

Sympathetic ophthalmia is:

Very uncommon

even after severe penetrating trauma or intraocular surgery.

The risk is higher after:

• Open-globe injury
• Repeated intraocular surgery
• Extensive uveal manipulation

but remains low overall.

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When It Can Appear

SO can begin:

• Within days
• Within weeks
• Within months
• Years or even decades after the inciting injury

Most cases occur relatively early after trauma, but:

A very remote history of ocular injury does not exclude the diagnosis.

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Important Clinical Trigger

Always ask about:

• Previous open-globe trauma
• Ocular surgery
• Multiple retinal procedures
• Previous removal or repair of a severely injured eye

A history of ocular penetration in a patient with bilateral granulomatous panuveitis should immediately raise suspicion for:

Sympathetic ophthalmia.

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What the Patient Usually Notices

Symptoms may include:

• Blurred vision
• Photophobia
• Ocular pain
• Redness
• Floaters
• Metamorphopsia

The fellow eye may initially develop subtle symptoms before severe inflammation becomes apparent.

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What the Anterior Segment Can Show

Typical findings include:

• Granulomatous keratic precipitates
• Anterior chamber cells and flare
• Posterior synechiae
• Iris thickening
• Ciliary injection

The degree of anterior inflammation varies.

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Vitreous Involvement

Vitreous inflammation may include:

• Cells
• Haze

This contributes to the classification as:

Panuveitis

rather than isolated choroiditis.

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Characteristic Posterior Segment Findings

Posterior manifestations may include:

• Multifocal serous retinal detachments
• Diffuse choroidal thickening
• Optic disc edema
• Choroidal infiltrates
• Dalen–Fuchs nodules
• Retinal edema

These findings can closely resemble:

Vogt–Koyanagi–Harada disease.

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Dalen–Fuchs Nodules

Dalen–Fuchs nodules are small yellow-white lesions located at the level of:

• RPE
• Bruch membrane

They correspond histologically to collections of epithelioid cells beneath the RPE.

They are characteristic but:

Not pathognomonic

and may also be seen in VKH.

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Serous Retinal Detachment

One of the most important vision-threatening findings is:

Exudative retinal detachment

caused by severe choroidal inflammation and breakdown of the outer blood-retinal barrier.

OCT is particularly useful for documenting:

• Subretinal fluid
• RPE undulations
• Choroidal thickening

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Histopathologic Pattern

Classic pathology shows:

• Diffuse granulomatous choroiditis
• Lymphocytes, predominantly T cells
• Epithelioid histiocytes
• Multinucleated giant cells

The choriocapillaris is often relatively spared early.

Dalen–Fuchs nodules may be present between:

• RPE
• Bruch membrane

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How the Diagnosis Is Made

There is:

No single confirmatory blood test

Diagnosis is based on:

1. Compatible bilateral granulomatous uveitis
2. History of prior penetrating ocular trauma or surgery
3. Characteristic multimodal imaging
4. Exclusion of important mimics

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Optical Coherence Tomography

OCT may demonstrate:

• Multifocal subretinal fluid
• RPE folds
• Septa within serous detachments
• Outer retinal disruption
• Choroidal thickening on enhanced-depth imaging

Serial OCT is valuable for monitoring treatment response.

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Fluorescein Angiography

FA classically shows:

• Multiple pinpoint areas of early hyperfluorescence
• Progressive leakage
• Pooling beneath areas of serous retinal detachment
• Optic disc leakage

This pattern strongly resembles VKH.

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Indocyanine Green Angiography

ICGA may show:

• Multiple hypofluorescent dark dots
• Delayed choroidal perfusion
• Diffuse choroidal inflammatory abnormalities

ICGA can reveal disease activity not obvious clinically.

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Fundus Autofluorescence

FAF may demonstrate:

• Hyperautofluorescent areas of active RPE stress
• Hypoautofluorescent areas of established RPE atrophy

It is useful for documenting:

Chronic RPE damage.

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B-Scan Ultrasonography

B-scan may demonstrate:

• Choroidal thickening
• Serous retinal detachment

It is particularly useful when:

• Media opacity limits fundus visualization

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Important Diagnostic Mimics

The major differential diagnoses include:

• Vogt–Koyanagi–Harada disease
• Sarcoidosis
• Tuberculosis
• Syphilis
• Posterior scleritis
• Primary vitreoretinal lymphoma
• Other granulomatous panuveitides

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Distinguishing SO From VKH

Sympathetic Ophthalmia

• Prior ocular trauma or surgery
• Bilateral granulomatous panuveitis
• Dalen–Fuchs nodules
• Serous retinal detachments

Vogt–Koyanagi–Harada Disease

• No preceding penetrating ocular injury
• May have neurologic/auditory symptoms
• May develop:
• Vitiligo
• Poliosis
• Alopecia

The ocular appearance can be nearly identical.

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Infectious Disease Must Be Excluded

Before major immunosuppression, evaluate for important mimics such as:

• Tuberculosis
• Syphilis

and other infections when clinically indicated.

This is especially important before:

• Biologic therapy
• Long-term systemic immunosuppression

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HLA Associations

Various HLA associations have been reported, including:

• HLA-DR4-related alleles

However:

HLA testing has no routine diagnostic role.

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Immediate Treatment Goal

The central objective is:

Rapid and sustained suppression of intraocular inflammation before irreversible retinal, choroidal, and optic nerve damage develops.

Treatment should generally be:

Aggressive from the outset.

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First-Line Systemic Treatment

Acute disease is usually treated with:

High-dose systemic corticosteroids

such as oral prednisone, often around:

1 mg/kg/day

depending on severity.

Severe disease may require:

IV methylprednisolone pulse therapy

for rapid control.

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Why a Slow Steroid Taper Matters

Inflammation may recur when corticosteroids are tapered too quickly.

Therefore tapering is usually:

Slow and guided by clinical and imaging evidence of quiescence.

OCT and angiography can detect persistent posterior inflammation even when symptoms improve.

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Early Steroid-Sparing Therapy

Modern management often favors:

Early introduction of immunomodulatory therapy

rather than relying on prolonged high-dose corticosteroids alone.

This reduces:

• Steroid toxicity
• Recurrence
• Chronic inflammation

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Common Immunomodulatory Agents

Options include:

• Mycophenolate mofetil
• Methotrexate
• Azathioprine
• Cyclosporine
• Tacrolimus

Choice depends on:

• Disease severity
• Comorbidities
• Patient age
• Specialist experience

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Biologic Therapy

Refractory or severe disease may respond to:

• Adalimumab
• Infliximab

Other biologic agents may be used in selected cases.

These generally require:

• TB screening
• Hepatitis screening
• Multidisciplinary monitoring

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Local Steroid Therapy

Periocular or intravitreal corticosteroid can be useful as an adjunct for:

• Persistent macular edema
• Asymmetric inflammation

However:

Local treatment alone is usually inadequate for a bilateral systemic autoimmune process such as SO.

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Role of Steroid Implants

Long-acting intravitreal corticosteroid implants may control inflammation in selected cases but carry risks including:

• Cataract
• Ocular hypertension
• Glaucoma

They are not a universal substitute for systemic immunomodulation.

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The Old “14-Day Enucleation Rule”

Traditional teaching stated that a blind traumatized eye should be enucleated within:

14 days

to prevent sympathetic ophthalmia.

This rule is now considered:

Oversimplified and not strongly evidence-based.

Because SO is rare and visual potential may be difficult to judge immediately after trauma, prophylactic removal should not be automatic.

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When Enucleation May Still Be Considered

Early enucleation may be considered when an injured eye is:

• Irreversibly blind
• Severely disorganized
• Painful
• Without realistic visual potential

The decision should balance:

• Possibility of visual recovery
• Structural integrity
• Pain
• Risk of infection
• Patient preference

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What to Do Once Sympathetic Ophthalmia Has Started

After SO has developed:

Removal of the exciting eye generally does not reliably improve inflammation or visual outcome in the sympathizing eye.

Therefore an eye with useful or potentially useful vision should not be removed simply because SO has begun.

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Enucleation vs Evisceration

Historically, enucleation was favored over evisceration because retained uveal tissue was thought to increase SO risk.

Modern data suggest the absolute risk after either procedure is:

Extremely low

but enucleation remains the traditional choice when removal of a severely traumatized eye is undertaken specifically in the context of concern about sympathetic ophthalmia.

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Management of Cataract

Chronic inflammation and steroid therapy can cause:

Cataract

Surgery should ideally be performed when inflammation has been:

Well controlled for a sustained period

with appropriate perioperative anti-inflammatory coverage.

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Management of Glaucoma

Glaucoma may result from:

• Chronic uveitis
• Peripheral anterior synechiae
• Corticosteroid therapy

Treatment may require:

• Topical medications
• Laser in selected situations
• Glaucoma surgery

while maintaining adequate inflammatory control.

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Macular Complications

Visual loss may result from:

• Persistent serous retinal detachment
• Cystoid macular edema
• RPE atrophy
• Subretinal fibrosis
• Photoreceptor loss

OCT is central to monitoring these complications.

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Follow-Up During Active Disease

Patients require:

Close and frequent review

with assessment of:

• Visual acuity
• Anterior chamber activity
• Vitreous inflammation
• IOP
• Optic nerve
• OCT
• Choroidal/retinal activity

Severe disease may initially require review:

• Every few days
• Weekly

depending on response.

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Long-Term Monitoring

Even after apparent remission, recurrence can occur.

Long-term follow-up should monitor for:

• Recurrent uveitis
• Cataract
• Glaucoma
• Macular edema
• RPE/choroidal atrophy
• Immunosuppressive drug toxicity

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Expected Visual Outcome

Modern aggressive immunosuppression has greatly improved prognosis.

Many patients can retain:

Useful central vision

if inflammation is treated early and sustained remission is achieved.

Poorer outcomes are associated with:

• Delayed diagnosis
• Recurrent inflammation
• Chronic serous detachment
• Glaucoma
• Macular scarring
• Optic nerve damage

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Major Ocular Complications

Potential complications include:

• Bilateral visual loss
• Cataract
• Secondary glaucoma
• Cystoid macular edema
• Serous retinal detachment
• Subretinal fibrosis
• RPE atrophy
• Chorioretinal scarring
• Optic nerve damage

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High-Yield Takeaways

• Sympathetic ophthalmia is a rare bilateral granulomatous panuveitis occurring after penetrating ocular trauma or intraocular surgery.
• The injured eye is the exciting/inciting eye, and the fellow eye is the sympathizing eye.
• The disease is thought to result from T-cell-mediated autoimmunity against previously sequestered ocular antigens.
• SO can occur days to decades after ocular injury, so even remote trauma is relevant.
• Classic posterior findings include multifocal serous retinal detachments, diffuse choroidal thickening, optic disc edema, and Dalen–Fuchs nodules.
• Dalen–Fuchs nodules are characteristic but not pathognomonic and may also occur in VKH.
• FA typically shows multiple pinpoint leaks with late pooling beneath serous detachments.
• OCT is essential for monitoring subretinal fluid, outer retinal injury, and choroidal thickening.
• The main clinical mimic is Vogt–Koyanagi–Harada disease; the key discriminator is a history of ocular trauma or surgery.
• Tuberculosis, syphilis, sarcoidosis, and other granulomatous disorders should be excluded when appropriate.
• Treatment requires prompt high-dose systemic corticosteroids.
• Because recurrence is common and long-term steroid toxicity is substantial, modern care often uses early steroid-sparing immunomodulatory therapy.
• Mycophenolate, methotrexate, azathioprine, cyclosporine, tacrolimus, and biologics such as adalimumab or infliximab may be used depending on severity.
• The traditional rule that a blind traumatized eye must be enucleated within 14 days is not supported as an absolute modern standard.
• Once SO has developed, removing the exciting eye does not reliably improve the fellow eye and should not be done solely for that purpose when the eye has useful visual potential.
• Long-term prognosis is substantially better with early aggressive control of inflammation and sustained immunomodulation.