Glaucoma occurring after closed vitrectomy.

Six of 20 eyes developed postoperative glaucoma within two to ten days after closed vitrectomy for vitreous hemorrhage. Intraocular pressure was greater than 40mm Hg in all six eyes, and three developed pressure greater than 60 mm Hg. Intraocular pressure in four eyes was controlled with medical antiglaucoma therapy and two eyes required anterior chamber irrigation. Six months postoperatively three of the eyes had normal pressures, one was hypotonous, and two developed increased intraocular pressure secondary to angle neovascularization. Three of the 14 eyes that did not develop glaucoma developed a cellular accumulation in the anterior chamber. The glaucoma was caused mainly by obstruction of the trabecular meshwork by degenerated red blood cells known as ghost cells. The cells may be identified by phase-contrast examination of anterior chamber aspirates. Glaucoma can be prevented through irrigation of the vitreous cavity at the time of vitrectomy ensuring that no cells and debris are left behind to migrate into the anterior chamber and obstruct the trabecular meshwork. This type of glaucoma is caused mainly by ghost cells, whereas hemolytic glaucoma is caused mainly by macrophages and red blood cell debris.