A prospective, randomized, double-blind study showed that glutathione-bicarbonate-Ringer's solution (BSS Plus) caused significantly less corneal swelling on the first postoperative day after pars plana vitrectomy than did lactated Ringer's solution. By the seventh postoperative day, no difference was seen between the two solutions. We found no correlation between the increase in corneal thickness and either the duration of intraocular irrigation or the volume of solution used or the presence or absence of the lens. No persistent corneal complications were seen.