A total of 50 trabeculectomies were carried out with pre- and postoperative medications using steroids and indomethacin, and also with the use of sodium hyaluronate during surgery. The postoperative course was followed by the prospective study protocol adopted by Shirato et al and the results were compared with the Shirato series of 145 trabeculectomies where the surgery was performed without the above medications and without the use of sodium hyaluronate. The shallow anterior chamber and choroidal detachment were less frequent, and the complication-free postoperative course was more frequent in the present than in the Shirato series. The state of the intraocular pressure control of the Shirato series was analyzed by the life-table method for the follow-up period of about 5 years. The final success rate in maintaining the intraocular pressure at or below 20 mmHg after the first trabeculectomy was 60.8 +/- 7.2 (SE) % in primary open-angle glaucoma, 64.2 +/- 12.1% in primary angle-closure glaucoma and 31.1 +/- 9.9% in secondary glaucoma. There were several cases where argon laser trabeculoplasty had been carried out before trabeculectomy. The success rate in these cases appeared to be no different from the rate in the rest of the eyes. In primary open-angle glaucoma, the second surgery after failed first trabeculectomy gave a similar success rate as the first surgery, but the third surgery after two failed trabeculectomies gave a very low success rate. The intraocular pressure distribution after one year showed a frequency of visual field deterioration was high in the order of the eyes with the intraocular pressure higher than 20 mmHg, those with 15-20 mmHg and those with lower than 15 mmHg.