OPTIC DISC TOPOGRAPHY BEFORE AND AFTER TRABECULECTOMY IN ADVANCED GLAUCOMA

BACKGROUND AND OBJECTIVE: To analyze changes in the optic disc topogra phy after filtration surgery. PATIENTS AND METHODS: Laser scanning tom ography was performed in 10 eyes of 9 patients (mean age 65.6 +/- 8.1 years; age range 55 to 75 years) after a mean follow-up of 3.7 months, and in 8 eyes of 7 patients (mean age 63.1 +/- 7.6 years; age range 5 5 to 75 years) after a mean follow-up of 13.1 months. RESULTS: Preoper atively, the mean intraocular pressure (IOP) was 24.4 +/- 6.9 mm Hg wi th maximal medication. Postoperatively at 3.7 months it was 11.0 +/- 2 .2 mm Hg, and at 12.1 months it was 13.6 +/- 2.8 mm Hg. An initial red uction in IOP of more than 30% at 3.7 months was achieved without medi cation in all bur 1 eye. After 12.1 months, an IOP reduction of more t han 30% was achieved in 6 of 8 eyes (1 with medication), while 2 eyes had IOP reductions of less than 15% (less than or equal to 3 mm Hg) de spite medication. In the 6 eyes, the optic disc cup volume showed a de crease of more than 30%, while the 2 eyes without marked IOP reduction s had slight increases in cup volume. Of the 2 eyes without marked dec reases in cup size, 1 had normal-tension glaucoma and 1 experienced an increase in IOP of more than 25 mm Hg during the first postoperative week. CONCLUSION: The postoperative IOP should be kept low enough to p ermit reversal of optic disc changes.