ABSTRACT
Background : Pterygium is a fibrovascular subconjunctival tissue also called Tenon’s Capsular growth occurring mostly in the palpebral fissure area from the nasal aspect towards the limbus over the Cornea and in this process the Corneal Pathology is changed especially the epithelium and bowman’s layer of the cornea are destroyed1. A major problem seen in most of postpterygium surgery is the complication of recurrence and it is usually seen in young patients with fleshy large pterygium1. This issue is addressed by Pterygium Surgery with either Conjunctival Autograft (CAG) or Amniotic Membrane Graft (AMG)1. Stem cells are present in limbal conjunctiva and in amniotic membrane, which provide a barrier between cornea and conjunctiva, preventing regrowth and also provide a smooth regular surface to the eyeball2. another reason and technique to prevent recurrence is by excising the pathological part of conjunctiva and resecting tenon’s capsule up to far periphery2. Aims and Objectives : The aim of the study is to investigate pre-operative and postoperative difference between the amount of astigmatism prior to the surgery and after the Pterygium Excision Surgery with either CAG or AMG. Materials and Method : A prospective cross-sectional study was undertaken of 26 cases, who underwent Pterygium Surgery under local anaesthesia with Conjunctival Autograft or Amniotic Membrane Graft for a period of one year in a Tertiary Healthcare Hospital. Pre-operative Best Corrected Visual Acuity, Anterior Segment Examination, Slit Lamp Examination, Dilated Retinoscopy and Fundus examination, Keratometry and Post mydriatic refraction was done. Then the patient underwent Pterygium Excision Surgery with Conjunctival Autograft or Amniotic Membrane Graft under local anaesthesia. All patients were re-examined 1 month after the surgery for final Refraction and Keratometry. Result : Among total of 26 patients, the comparison between pre- and postoperative values of Refraction and of Corneal Astigmatism was performed using z test. The pre-operative Mean for Astigmatism was 1.70 and SD was 0.43. The postoperative mean for Astigmatism was 0.57 and SD was 0.26. The pre-operative Keratometry mean was 2.73 and SD was 0.14. The Post operative Keratometry Mean was 1.50 and SD was 0.55. (p value, 0.0001) Conclusion: Pterygium is a lesion which also affects the ocular surface, thus leading to one of the causes for ocular surface abnormality. Pterygium surgeries results in elimination of the Pulling Factor and Corneal Curvature thus reducing or eliminating Astigmatism and thereby providing better visual restoration and cosmetic outcome