[External trabecular excision--alternative to filtering glaucoma operation in patients with open angle glaucoma]

Abstract

Background: Postoperative complications concerning glaucoma filtering surgery (trabeculectomy, goniotrepanation) often include hypotonia that may lead to athalamia or choroidal detachment, which are difficult to handle. Cystic non filtering blebs are due to postinflammatory reactions, and may limit the success of filtering surgery. Aim of the study was to compare the success and the complications of a new operating technique, which will be described, with those of usual glaucoma filtering surgery.

Patients and methods: In 24 open angle glaucoma patients with mean intraocular pressure of 28.12 mm Hg (+/- 8.6) we performed external trabecular excision in 25 eyes since June 1997. Preoperative visual acuity and peak intraocular pressure were compared retrospectively in all eyes with the values of the first postoperative day, in 22 eyes after one month and in 17 eyes after 3 months.

Results: Intraocular pressure measured between 0 mm Hg and 16 mm Hg on the first postoperative day (7.64 mm Hg +/- 4.3), after one month between 10 mm Hg and 30 mm Hg (17.81 mm Hg +/- 5.5) and after 3 months between 9 mm Hg and 26 mm Hg (15.29 mm Hg +/- 4.2). After 1 month 10 of 22 (45%) and after 3 months 7 of 17 eyes (42%) required antiglaucomatous drugs; 3 eyes needed gonitrepanation (2 weeks, 1 month, 3 months after ETE). Concerning postoperative complications, we observed 6 choroidal detachments, once erythrocoytes in the anterior chamber, twice hyphemata, twice inflammatory reaction in the anterior chamber, two flat anterior chambers and twice a positive seidel test.

Conclusion: Complications after ETE are similar to those after filtering surgery. Postoperative intraocular pressure dip after ETE in most eyes was not as pronounced as after goniotrepanation or trabeculectomy, and postoperative complications were all reversible. 45% of the eyes again needed antiglaucomatous drugs after one month and 42% after 3 months. A prospective long-term study has to verify the success respectively the complications of ETE.