A 48-year-old woman from coastal Tamil Nadu presents with a 5-year history of a nasal conjunctival mass that has progressively encroached onto her right cornea. She reports mild irritation but denies significant vision loss. On slit-lamp examination, the pterygium head is noted to be 2 mm onto the cornea with active vascularity. Anterior segment OCT shows corneal flattening in the area of pterygium invasion. She is concerned about cosmetic appearance and wishes treatment. Which of the following is the MOST appropriate management?

Explanation

## Management of Progressive Pterygium ### Clinical Context This patient has: - **Progressive pterygium** (5-year history with active encroachment) - **Cosmetic concern** (patient motivation for treatment) - **Mild symptoms** (not severe irritation) - **Corneal involvement** (2 mm onto cornea with induced astigmatism) - **Active vascularity** (suggests ongoing progression) ### Indications for Surgical Intervention **Key Point:** Surgical excision is indicated when pterygium: 1. Threatens the visual axis (approaching or covering pupil) 2. Causes significant induced astigmatism or refractive error 3. Is cosmetically unacceptable to the patient 4. Causes persistent irritation unresponsive to medical therapy 5. Shows rapid progression This patient meets criteria 2, 3, and 5. ### Surgical Technique & Adjunctive Therapy | Approach | Recurrence Rate | Indications | Complications | |----------|-----------------|-------------|----------------| | **Simple excision** | 15–50% | Low-risk cases | High recurrence | | **Excision + Mitomycin C** | 5–15% | Moderate-risk, primary cases | Scleral necrosis if prolonged exposure | | **Excision + Conjunctival autograft** | 5–10% | High-risk, recurrent cases | Graft failure (rare) | | **Excision + Beta radiation** | 2–5% | Recurrent cases | Scleral necrosis, cataract | **High-Yield:** **Conjunctival autograft** is the gold standard for primary pterygium surgery in this patient because: - Reduces recurrence to 5–10% (vs. 15–50% with simple excision) - Provides better cosmetic outcome - Restores normal conjunctival tissue - Mitomycin C can be combined for additional benefit - Lower risk of late complications compared to radiation ### Why Mitomycin C? **Mnemonic: MMC = Mitosis Mitigation Chemotherapy** - Inhibits fibroblast proliferation - Applied intraoperatively (0.4–0.5 mg/mL for 2–4 minutes) - Reduces myofibroblast activation and recurrence - Risk: Scleral necrosis if concentration too high or exposure prolonged ### Why NOT the Other Options **Medical Management Alone (Lubricants + NSAIDs)** - Appropriate for **asymptomatic, stationary** pterygium - This patient has **progressive** disease with cosmetic concerns - Will NOT halt corneal invasion or induced astigmatism - Patient explicitly desires treatment **Topical Corticosteroids** - May reduce acute inflammation temporarily - Do NOT address underlying fibroblastic proliferation - Prolonged use risks steroid-induced glaucoma and cataract - Will NOT prevent recurrence or progression **Beta Radiation as Primary Treatment** - Reserved for **recurrent pterygium** after failed surgical excision - Risks scleral necrosis, cataract, and late radiation effects - Overkill for a primary case - Conjunctival autograft is safer and equally effective for primary cases ### Surgical Algorithm ```mermaid flowchart TD A[Pterygium diagnosed]:::outcome --> B{Symptomatic or<br/>threatening visual axis?}:::decision B -->|No| C[Observation + lubricants]:::action B -->|Yes| D{Primary or<br/>recurrent?}:::decision D -->|Primary| E[Excision + Conjunctival<br/>autograft ± MMC]:::action D -->|Recurrent| F[Excision + MMC or<br/>Beta radiation]:::action E --> G[Low recurrence 5-10%]:::outcome F --> H[Very low recurrence 2-5%]:::outcome ``` **Clinical Pearl:** Conjunctival autograft is harvested from the superior bulbar conjunctiva (away from the pterygium site) and sutured to the excision bed with fibrin glue or sutures. The graft provides a physical barrier and restores normal conjunctival architecture, reducing recurrence and improving cosmesis. [cite:Khurana 7e Ch 5; American Academy of Ophthalmology Cornea and External Disease]