Elevation of intraocular pressure after pars plana vitrectomy.

To determine the incidence and causes of increased intraocular pressure (IOP) after pars plana vitrectomy with the vitrophage, we studied 118 eyes under-going vitrectomy during a one-year period. Fifty-one (43%) were in diabetic patients; 67 (57%) were in nondiabetics. Of the entire group, 33 (28%) developed a postoperative increase in IOP, which was defined as a rise in IOP of at least 10 mm Hg above the preoperative level by applanation tonometry. Of the diabetic eyes 25 (49%) developed increased IOP; 11 (22%) of these eyes required surgical intervention for control of IOP. Of the nondiabetic eyes eight (12%) developed increased IOP postoperatively; all were either transiently elevated or medically controllable. Postoperative rubeosis iridis occurred only in diabetic eyes.