Immediate postoperative use of a topical agent to prevent intraocular pressure elevation after pars plana vitrectomy with gas tamponade

To determine whether a single topical aqueous suppressant applied immediately after pars plana vitrectomy with long-acting gas tamponade prevents intraocular pressure (IOP) elevation. Fifty patients who met the inclusion criteria and underwent pars plana vitrectomy with long-acting gas tamponade were randomized to receive a combination of timolol maleate and dorzolamide hydrochloride, long-acting timolol alone, dorzolamide alone, or placebo at the conclusion of surgery. The IOP was checked by a portable, handheld tonometer (Tono-Pen) at the conclusion of surgery and at 5 hours, 1 day, and 1 week after surgery. There were no significant differences in IOP among the groups at the conclusion of surgery. The IOP at 5 hours after surgery (27.0 vs 17.4 mm Hg; P