Trabeculectomy in diabetic patients with glaucoma.

Forty-one eyes of 41 patients with diabetes mellitus who underwent trabeculectomy over a 4-year period were compared with 41 age- and sex-matched controls, who were also matched for date of operation and surgical technique. The two groups were comparable for glaucoma diagnoses, duration of glaucoma before admission and number of ocular hypotensive medications. The intraocular pressures at diagnosis and on admission were similar. Post-operative complications were equally frequent. The mean intraocular pressure at 6 months was significantly lower in the control group, and fewer diabetic patients achieved either an intraocular pressure < 21 mmHg or successful drainage (defined as an intraocular pressure < 21 mmHg on no treatment) at 6 months and at the final visit, after similar periods of follow-up. Trabeculectomy in diabetic patients with pre-existing retinopathy resulted in a significantly higher intraocular pressure at 6 months than when no retinopathy was present.