[Ab externo erbium YAG laser sclerostomy versus conventional trabeculectomy. Treatment of glaucoma patients].

PURPOSE

This study was conducted to compare the efficacy of the Er-YAG laser sclerostomy ab externo versus trabeculectomy in the treatment of primary open-angle glaucoma.

METHODS

Twelve patients with POAG underwent ab externo laser sclerostomy using an Er-YAG laser (Sklerostom 2.9; lambda = 2940 nm, t = 200 microseconds, 2 Hz, 400 microns, 15 mJ). Only local medication was used, and there were no risk factors for failure. As a control group 12 patients out of 248 standardized trabeculectomies were matched in terms of age, sex, diagnosis and local medications. No antimetabolites were used in either group.

RESULTS

After a follow-up of 9 months in the sclerostomy group 53%; (7/12; P = 0.03) showed a patent fistula in comparison of 100% in the trabeculectomy group. There was a significantly lower mean IOP during the first postsurgical week in the group of sclerostomies (3.6 +/- 1.5 mmHg versus 7.5 +/- 2.7 mmHg; P = 0.0001) with a higher incidence of choroidal detachments (9/12 versus 2/12; P = 0.004). The choroidal detachments lasted longer in the sclerostomy group (3.5 months versus 0.3 months; P = 0.014). Iris incarcerations were found only in sclerostomies (7/12; P = 0.05).

CONCLUSIONS

Based on these findings, Er-YAG laser sclerostomy prooved to be less effective than trabeculectomy in the treatment of glaucoma patients. Er-YAG laser sclerostomies were associated with a higher incidence of postsurgical complications such as hypotony, choroidal detachments and iris incarcerations. At this point Er-YAG laser sclerostomy is not superior to conventional trabeculectomy.