What are the implications and treatment options for a patient with a pocket of fluid in the sclera, potentially with underlying inflammation, infection, or trauma, and a possible history of pre-existing eye conditions or autoimmune disorders?

Pocket of Fluid in the Sclera

Immediate Clinical Assessment

A pocket of fluid in the sclera requires urgent ophthalmologic evaluation to differentiate between post-surgical filtering blebs, infectious scleritis, posterior scleritis with sub-Tenon fluid, or conjunctival chemosis, as the treatment approach differs dramatically and delays in diagnosing infectious causes can lead to rapid ocular destruction. 1, 2

Critical History Elements

• Timing of onset and prior ocular surgery (especially pterygium, cataract, vitreoretinal surgery, or trabeculectomy) are the most common predisposing factors for infectious scleritis 1, 2
• Recent ocular trauma, contact lens use, "eye-whitening" procedures, or subtenon steroid injections raise suspicion for infection 2
• Deep ocular pain with painful eye movements suggests posterior scleritis rather than superficial processes 1
• Symptoms of systemic vasculitis (temporal tenderness, jaw claudication, weight loss, proximal myalgia) or connective tissue disorders (rheumatoid arthritis) must be assessed, as these are commonly associated with necrotizing scleritis 3, 4

Physical Examination Findings

• Measure visual acuity and intraocular pressure at presentation 1
• Slit-lamp biomicroscopy should identify:
  • Post-surgical blebs appearing as elevated, fluid-filled conjunctival elevations in the superior quadrant 1
  • Scleral necrosis, hypopyon, unifocal/multifocal scleral abscesses, or mucopurulent discharge indicating infectious scleritis 2
  • Conjunctival chemosis with clear fluid accumulation suggesting allergic or inflammatory causes 1
• Dilated fundus examination to assess for posterior segment involvement 1

Diagnostic Imaging

• B-scan ultrasonography is essential to identify the "T-sign" (fluid in sub-Tenon space around the optic disc) pathognomonic for posterior scleritis 1
• Anterior segment optical coherence tomography can visualize retrocorneal membranes or detached Descemet's membrane that may be masked by edema 5
• Ultrasound biomicroscopy is particularly helpful in traumatic cases to locate foreign bodies and assess scleral integrity 5

Treatment Algorithm Based on Etiology

Infectious Scleritis (Most Urgent)

Before excluding infection, obtain scleral scrapings and cultures, then immediately initiate empiric broad-spectrum topical AND systemic antibiotics while awaiting laboratory results. 2

• Topical fluoroquinolone (ciprofloxacin 0.3%, ofloxacin 0.3%, or levofloxacin 1.5%) every 1-2 hours while awake 6
• Systemic antibiotics are required due to limited penetration into the avascular sclera 7, 2
• Most cases require both aggressive medical and surgical treatment for favorable outcomes 2
• Do NOT use corticosteroids until infection is definitively ruled out, as this can lead to rapid scleral destruction 3, 2

Posterior Scleritis (Autoimmune/Inflammatory)

Initiate systemic corticosteroids as first-line therapy with oral prednisone 1 mg/kg/day and gradual taper. 1

• Systemic corticosteroids are indicated for severe acute and chronic inflammatory processes involving the eye, including diffuse posterior uveitis, choroiditis, and optic neuritis 8
• Monitor for steroid responsiveness and elevated IOP during treatment 5
• Consider workup for underlying systemic vasculitis or connective tissue disorders (ESR, CRP, rheumatoid factor, ANA) 4

Post-Surgical Filtering Blebs

• Leaking blebs require pressure patching or surgical revision 1
• Functional blebs should be observed with routine monitoring 1
• Topical antibiotics may reduce risk of secondary infection if bullae rupture 5

Conjunctival Chemosis

• Treat underlying allergic conjunctivitis or inflammation with topical anti-inflammatory agents 1
• Address venous congestion if present 1

Critical Pitfalls to Avoid

• Never empirically treat with corticosteroids alone without first ruling out infection, as necrotizing infectious scleritis can destroy all structural components of the sclera within days 3, 2
• Do not delay diagnostic workup for cultures and imaging, as infectious scleritis has a poor prognosis when diagnosis is delayed 2
• Recognize that autoimmune scleritis and infectious scleritis have similar clinical presentations, making thorough diagnostic testing essential before excluding infection 2
• Avoid patching the eye in suspected infectious cases, as this increases risk of secondary bacterial keratitis 6