Enhancement of the success rate in trabeculectomy: large-area mitomycin-C application

To compare the effects of variable mitomycin-C (MMC) applications during trabeculectomy on target intraocular pressure (IOP), number of antiglaucomatous therapy, bleb morphology and surgical complications.

66 glaucoma cases who underwent trabeculectomy combined with small-area (Group 1) or large-area (Group 2) MMC application were included. This study is a retrospective case series comparison. In Group 1, MMC had only been applied to the scleral flap area, whereas additional MMC applications were performed on upper temporal and nasal quadrant in Group 2. The cases with diabetes, narrow angle glaucoma, secondary glaucoma, history of previous ocular surgery and follow-up period less than 2 years were exluded from the study. A routine ophthalmological examination was performed in all cases and IOP measurements, morphology and the function of the blebs, necessity for antiglaucomatous medications and complications at first month and second year were evaluated.

There were 32 cases (48.5%) in Group 1 and 34 cases (51.5%) in Group 2. The mean IOPs were 12.6 +/- 5.5 and 10.8 +/- 5.3 mmHg at first month (P > 0.05), whereas 14.4 +/- 2.8 and 10.1 +/- 2.6 mmHg at second year, respectively (P < 0.05). The mean number of medications were 3.3 +/- 1.6 and 3.2 +/- 0.2 preoperatively (P > 0.05), whereas 0.8 +/- 1.2 and 0.26 +/- 0.70 at second year (P < 0.05). The number of diffuse blebs was higher in Group 2 whereas the number of cystic blebs was higher in Group 1 (P > 0.05). There was no difference between two groups with regards to the number of eyes with hypotonia (P > 0.05).

Large-area MMC application seems to increase long-term success without increasing the complication rates in trabeculectomy.