Raised intraocular pressure with topical steroids after trabeculectomy.

A prospective study of 87 eyes of 52 patients with primary open-angle glaucoma showed a significant steroid-induced rise in intraocular pressure in the 4 weeks after trabeculectomy in 23% of eyes. The steroid response rate was lower (17%) in those eyes that had trabeculectomy without a prior trial of medical therapy than in those who had surgery only after failure of medical therapy (36%), but this difference just failed to reach statistical significance. The responders were not significantly different from the non-responders as regards level of intraocular pressure or severity of visual field loss at diagnosis. The frequency of response was lower than that expected in the normal and in the glaucoma population and fell further in the late post-operative period when only 3 of 8 previously responsive eyes submitted to re-challenge with topical steroids showed persisting responsiveness. Topical steroids may be the commonest cause of high intraocular pressure in the first weeks or even days after trabeculectomy. Decisions about long-term supplementary medical therapy should therefore only be taken several weeks after withdrawal of the post-operative steroid drops.