A One Year Randomized Controlled Trial to Compare the Effectiveness of Conjunctival Autograft versus Conjunctival Autograft Combined With Intraoperative Mitomycin-C Following Pterygium Excision

Abstract

BACKGROUND AND OBJECTIVES: ABSTRACT Pterygium is a triangular , fibrovascular encroachment of bulbar conjunctiva on to the cornea and is horizontally situated in the inter palpebral fissure on either the nasal or temporal side of the cornea. Prevalence of pterygium is high in the tropical belt of the world, especially in India where hot, sunny and dusty weather favours its growth. Indications for treatment vary from minor cosmetic disfigurement to significant visual loss. Surgical removal remains the mainstay of treatment ,basic procedure being complete excision leaving a bare area of sclera. The recurrence rate of this traditional Bare Sclera technique ranges from 24% - 89%. In recent two years, 2 surgical techniques have become increasingly accepted as methods likely to prevent pterygium recurrence, namely Mitomycin C application and conjunctival autograft transplantation. Conjunctival autograft technique is reported to have recurrece rates ranging from 2% to 39%. Adjunctive use of Mitomycin C in pterygium surgery is reported to be a safe and effective procedure. Conjunctival autograft combined with intra operative application of Mitomycin C is reported to have recurrence rates ranging from 2% to 9%. This study is undertaken to compare the recurrence rates of pterygium in conjunctival autograft technique versus conjunctival autograft combined with Mitomycin C and also to study the complications associated with the two procedures. METHODOLOGY: The present prospective randomized controlled trial was conducted at KLES Hospital & MRC , Belgaum, over a period of one year , from 1 x st January 2008 to 31 st December 2008. In the study, 50 eyes of 47 patients who met the inclusion criteria were included. After detailed preoperative evaluation, informed written consent was taken and they were randomized into two groups to receive either conjunctival autograft or conjunctival autograft combined with intraoperative application of 0.02%(0.2 mg/ml) Mitomycin C for 1 minute ,following excision of pterygium. All 50 eyes completed the study with a minimum follow up of 4 months. A detailed documentation of the post operative complications and recurrence at the end of the study was done. OBSERVATIONS AND RESULTS: The majority of patients in our study were in the age group 40-49 years (32%). Mean age in Group A was 43.2 years (range 20-62 years) and in Group B was 45.2 years (range 30-65 years). Out of the 50 eyes of 47 patients who presented to us with pterygium, 22 (44%) were that of men and 28 (56%) were that of women. Out of the 50 cases 47 (94%) were primary pterygium and 3 (6%) were recurrent pterygium. Among 50 cases, only 1 (2%) temporal pterygium was included in the study. Majority (56%) of the eyes with pterygium in this study were those of outdoor workers. A total of 22 (44%) eyes had intra operative and post operative complications in the study. Out of these 22 eyes, 10 (40%) eyes belonged to Group A and 12 (48%) eyes to Group B. The difference was not statistically significant (p value = 0.5). Among the significant complications, there were 4 cases of Granuloma formation (8 %) (2 in CAG group and 2 in CAG + MMC group), 3 cases of Superficial Punctate Keratitis ( CAG + MMC group) and 1 case of scleral blanching( CAG + MMC group.) xi Of the 50 cases, there were no recurrence seen in any eye in both the groups after a minimum follow up period of 4 months and maximum period of 11 months. CONCLUSION: From our study, we conclude that both Conjunctival Autograft technique and Conjunctival autograft combined with intraoperative application of 0.02%Mitomycin C for one minute following Bare sclera excision of pterygium are equally effective in preventing the recurrence of pterygium. Both the procedures appear to be safe and acceptable as adjuvants in pterygium surgery.