A randomized, prospective study on 68 eyes of 54 patients with progressive, uncontrolled, noninflammatory open-angle glaucoma showed that eyes that received topical prednisolone 1% had a lower intraocular pressure (IOP) 18 months following trabeculectomy than the eyes that received no prednisolone. The addition of systemic prednisone had no definite further effect. In the present study, we reevealuated 58 eyes of 45 of these patients 5 years after the time of initial surgery. The number of cases lost to follow up was similar in the steroid and the nonsteroid-treated groups. Mean IOP of the steroid-treated patients was 14.5 +/- 1.8 mm Hg, and of the nonsteroid-treated patients, 19.3 +/- 2.1 mm Hg. Visual field, optic disc, and IOP were stabilized in 94% of the steroid-treated cases and in 43% of the nonsteroid-treated cases. Thus, postoperative steroids significantly increased the success rate of trabeculectomy in these eyes, and the eyes with lower IOPs had a significantly better prognosis than those with higher IOPs.