Effect of intraoperative use of topical mitomycin C on intraocular pressure in patients with pterygium excision

Aim: To determine the effect of intraoperative adjunctive topical mitomycin C on intraocular pressure in patients undergoing pterygium excision. Methods: This was a descriptive interventional case series of 102 patients (118 eyes) with different grades of pterygium treated from 1995 to 2008. All patients underwent pterygium excision with intraoperative mitomycin C 0.2 mg/mL administered for 1 to 5 minutes. Changes in intraocular pressure were recorded on days 1 and 7, and at 3 months. Data were analysed using proportion, group means, standard deviations, analysis of variance, and paired Student t test. Results: There was no significant decline in intraocular pressure throughout the follow-up period (p = 0.435, Student t test). At 3 months postoperatively, 109 eyes (92.4%) had no changes in intraocular pressure >5 mm Hg, of whom 78 (72%) experienced minimal changes that were not statistically significant. Conclusions: Intraoperative topical administration of mitomycin C has a minimal effect on lowering intraocular pressure in patients with pterygium. These results do not support the trans-scleral effect of mitomycin C on the ciliary body as an intraocular pressure-lowering mechanism in glaucoma filtering surgery.