COMPARISON OF EFFICACY OF PTERYGIUM RESECTION WITH CONJUNCTIVAL AUTO GRAFT VERSUS AMNIOTIC MEMBRANE GRAFT TO REDUCE THE RECURRENCE RATE

Abstract

Background: Conjunctival autograft (CAG) and amniotic membrane graft (AMG) are established methods for reconstructing the ocular surface after pterygium excision, but comparative recurrence estimates vary across settings and surgical protocols. We compared 3-month recurrence after CAG versus AMG in adults undergoing primary pterygium excision at a tertiary hospital in Pakistan. Methods: This single-center, parallel-group randomized trial included 590 participants (295 per group), aged 20-50 years, with primary pterygium measuring 2-4 mm and symptom duration of 6 months or less. The primary outcome was fibrovascular corneal regrowth of at least 2 mm by 3 months. Analyses included risk difference (RD), risk ratio (RR), odds ratio (OR), number needed to treat (NNT), modified Poisson and logistic regression, marginal standardization with 2,000 bootstrap resamples, exploratory interaction analyses, and beta binomial Bayesian sensitivity analyses. Results: The primary outcome was available for all 590 participants. Recurrence occurred in 30/295 CAG participants (10.2%) and 53/295 AMG participants (18.0%). CAG reduced recurrence by 7.8 percentage points (95% CI 2.2-13.4), corresponding to an RR of 0.57 (95% CI 0.38-0.86; P=0.006) and an NNT of 12.8 (95% CI 7.5-45.8). The adjusted RR was 0.55 (95% CI 0.36-0.83), and the adjusted OR was 0.47 (95% CI 0.28-0.78). Standardized recurrence risks were 10.0% with CAG and 18.2% with AMG (adjusted RD -8.2 percentage points; bootstrap 95% CI -13.6 to -2.3). The posterior probability that CAG reduced recurrence was 99.69%. Conclusions: CAG produced a clinically and statistically lower 3-month recurrence risk than AMG. The finding supports CAG as the preferred reconstruction for routine primary pterygium when healthy conjunctiva is available, while the short follow-up and absence of safety, visual, and patient-reported outcomes limit conclusions about overall comparative benefit.