Early results of suprachoroidal drainage tube implantation for the surgical treatment of glaucoma.

PURPOSE

To evaluate the efficacy and safety of suprachoroidal silicone tube shunt implantation in glaucoma.

PATIENTS AND METHODS

Twenty-four glaucomatous eyes unresponsive to medical treatment were included, 7 of them had earlier trabeculectomy. After preparation of a limbus-based scleral flap, 1.5 mm deep sclerotomy was made adjacent to scleral flap opening. Posterior end of the silicone tube was placed posteriorly in suprachoroidal space, anterior end was placed into anterior chamber. Intraocular pressure (IOP) and best corrected visual acuities (BCVA) were measured preoperatively and postoperatively on the first day, at the first week, in the first, third, sixth, twelfth, and eighteenth months. Postoperative IOP >21 mm Hg, <5 mm Hg (after 3 months), or additional glaucoma surgery were accepted as failure. Eyes not failed and not on supplemental medical therapy are considered as complete success. Eyes that have not failed, with or without supplemental medical therapy, are considered as qualified success. Hypotony was defined as early, when IOP below 5 mm Hg was observed within 4 weeks.

RESULTS

Mean postoperative follow-up period was 34.4±23.7 weeks (range 4 to 78 wk). Complete success rates were 95.8%±4.1 at the first week, 79.2%±8.3 in the first and the third month, 63.3%±12.0 for the sixth and twelfth month. Qualified success rates were 95.8%±4.1 in the first week, 87.5%±6.8 in the first, third, sixth, twelfth months. Mean postoperative IOP's (8.5±4.9mm Hg, 12.9±5.6 mm Hg, 17.0±7.9 mm Hg, 15.3±3.6 mm Hg, 18.3±6.0, 15.1±6.0 mm Hg, respectively for the first week, first, third, sixth and twelfth mo) were significantly lower than preoperative mean IOP's. The success rates in cases without earlier trabeculectomy were significantly higher than in cases with earlier trabeculectomy (P=0.035). Postoperative first day mean±SD BCVA value was significantly lower than preoperative value (P=0.004). Failure was seen in 7 eyes of which 3 of them underwent reoperation for glaucoma. Early hypotony was seen in 6 eyes. No infection, choroidal, or retinal detachment was seen. There was a fibrin reaction in the anterior chamber in 3 patients. Two patients had intracameral bleeding, 1 of them underwent anterior chamber lavage.

CONCLUSIONS

Suprachoroidal tube drainage of aqueous humor from the anterior chamber to the suprachoroidal space is effective in reducing IOP in glaucoma patients, with lower serious complication rates, and may be preferred as initial surgery in cases without earlier trabeculectomy.