Anterior Segment Optical Coherence Tomography Study of Pterygium in Conjunctival - Limbal Autograft Transplantation

Abstract

Introduction: Progressive, gradual, non-malignant proliferation of fibro-vascular tissue, occurring due to repetitive limbal stem-cell irritation & neovascularization, is referred to as pterygium. It is widespread in equatorial regions of the world, with a prevalence of 22% over a well defined ‘pterygium belt’. pterygium excision leaving bare sclera leads to the re occurrence, where as supplementing bare sclera with conjunctival autograft reduces the recurrence up-to 6%. Objective: Assessment of pterygium thickness pre-operative ly & post-surgery keratectomy area along with graft thickness after conjunctival limbal autograft transplantation (CLAT) surgery by anterior segment optical coherence tomography (AS- OCT). Method: 50 patients with primary pterygium were distributed age wise in 4 groups of 20-39, 40-59, 60-79 & 80-99 years. Anterior segment imaging was performed with RT-vue spectral domain AS-OCT. pterygium thickness pre-operatively & keratectomy area along with autograft thickness after CLAT surgery was evaluated for a follow-up period of 3 months. Results: the pre-op pterygium & 3 months post-op keratectomy area thickness at apex for (group 1) were 854um & 573um, (group 2) were 855um & 578um, (group 3) were 859um & 574um and (group 4) were 868um & 575um. Similarly at limbus for (group 1) are 1.13um & 720um, for (group 2) are 1.14um & 725um, for (group 3) are 1.19um & 718um, for (group 4) are 1.24um & 714um. Reduction in graft thickness in 3 months follow period for (group 1) was 311um, (group 2) 304um, (group3) 303um & (group 4) 313um respectively. Conclusions: CLAT ascertains to be the ideal treatment modality for pterygium management in terms of decreasing the complications & recurrence rate. Also, AS-OCT is the optimal investigating modality in assessment of pterygium before & after CLAT surgery.