Assessment of preoperative and postoperative changes in keratometry reading and corneal astigmatism after pterygium excision with conjunctival autograft transplantation

Pterygium is a wing shape fibrovascular degeneration ofsubconjunctival tissue. It destroys bowman’s membraneand corneal stromaby proliferating as vascularized granulation tissue. Ultraviolet B the main etiological factor mutates p53 tumorsuppressor gene presentat limbal stem cell and leads to overexpression ofTGF-beta and VEGF which results in upregulation of collagenase,cellular migration and angiogenesis. Elastotic degeneration of collagen and subepithelial fibrovascular tissue are the characteristic pathological featureof the pterygium. Pterygiaare thick and vascular when early but becomes pale and thin when cease toprogress       and leads to formation ofdense fibrous tissues and development of considerable corneal astigmatism. Pterygiumexerts a tractional force on cornea, which results in flattening of cornealcurvature   in horizontal meridianleading to with-the-rule astigmatism. Flattening also occurs dueto pooling of tears near the head ofpterygium. Mostpatient of pterygium complaints of foreign body sensation, lacrimation,redness, dryness and itching.Spatial contrast sensitivity and glare disability are worsened in patients even whenthe visual acuity is minimally affected. Cosmetic reasons, visual impairment,motility     restriction is some ofthe indication for pterygium surgery.

Pterygiumexcision is the mainstay of treatment butwith high tendency to                          reoccur. The gold standard intreatment of pterygium is pterygium excision with autograft implantation which has low rateof recurrences and complication. The present study aims to evaluate keratometryreadings and corneal astigmatic changes following pterygium excision withconjunctival autograft transplantation using fibrin glue. Since a few studieshave been done on this aspect therefore this study has been undertaken.