Incidence of disc hemorrhages in open-angle glaucoma before and after trabeculectomy.

PURPOSE

To investigate the effects of reduction of intraocular pressure (IOP) by surgical intervention on the frequency of disc hemorrhages in eyes with primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG).

DESIGN

Retrospective study.

METHODS

We studied 99 eyes of 99 patients with POAG and 50 eyes of 50 patients with NTG, who underwent trabeculectomy with adjunctive mitomycin C (MMC) and were followed regularly at 1 to 3-month intervals at the Glaucoma Service of Gifu University Hospital. We applied Kaplan-Meier life-table analysis for the detection of disc hemorrhages before and after trabeculectomy.

RESULTS

Trabeculectomy significantly reduced IOP (in POAG: 19.6 +/- 4.4 down to 11.1 +/- 4.2 mm Hg; in NTG: 15.3 +/- 1.5 down to 11.3 +/- 4.5 mm Hg; mean +/- SD). Life-table analysis revealed that the final cumulative probability of detecting a disc hemorrhage after surgery in POAG was 5.5 +/- 2.2% (calculated probability +/- SE) and was significantly lower than that (33.4 +/- 7.8%) before surgery (P < 0.0001, log-rank test). Likewise, the final probability after surgery in NTG was 23.1 +/- 6.3% and was significantly lower than that (42.1 +/- 8.8%) before surgery (P = 0.0063, log-rank test).

CONCLUSIONS

IOP reduction via surgical intervention significantly decreases the frequency of disc hemorrhages in open-angle glaucoma patients.