Use of mitomycin C with conjunctival autograft in pterygium surgery in Asian-Canadians

Objective: To determine whether using mitomycin C (MMC) before applying con junctival autograft is better than conjunctival autograft alone in preventi ng the recurrence of pterygia in an Asian-Canadian population. Design: Nonrandomized, retrospective, comparative case series. Participants: A total of 159 patients were included in the study. Seventy p atients (76 eyes) received MMC (0.25 mg/ml for 1 minute) with conjunctival autograft; 89 patients (98 eyes) received conjunctival autograft alone. Intervention: All patients had primary (first-occurrence) pterygia excised and conjunctival autograft applied with or without MMC adjunct. Main Outcome Measures: Recurrence of pterygia was monitored for up to 1 yea r after the operation. Any complications (e.g., scleral thinning and necros is) were documented. Results: Patients' pterygia were examined on presentation and were graded 1 through 3. Grade I pterygia were fibrovascular proliferations extending up to one quarter the diameter of the cornea; grade 2 extended between one qu arter to one half the distance across the cornea; and grade 3 extended beyo nd the visual axis. In the more severe pterygia group (grades 2 and 3 combi ned), there was significantly less pterygium recurrence in the MMC/autograf t group (7%) compared with the autograft alone-treated group (26%). There w as no significant difference in recurrence between groups for less severe g rade pterygia (grade 1). The recurrence rate of all pterygia in the MMC/aut ograft group was 9% compared with 18% for the conjunctival autograft group. This difference was not statistically significant, however, because of a s mall sample size. There were no significant complications in either group a nd no difference between groups in complication rates. Conclusions The authors suggest using MMC in patients with more severe pter ygia as an adjunct to conjunctival autograft to lower the recurrence rate. Combining the use of MMC with conjunctival autograft allows for decreased d osage and time of intraoperative exposure of mitomycin, thereby making it s afer for application.