Oversized donor grafts in penetrating keratoplasty. A randomized trial.

One hundred seventy-three aphakic or phakic corneal transplants were analyzed in a prospective randomized study to determine the effect of oversized corneal donor buttons on intraocular pressure, corneal curvature and astigmatism, wound dehiscence, and anterior chamber depth. We compared 93 oversized grafts with 80 same-sized grafts. In aphakic eyes, oversized grafts showed a trend toward lower incidence of elevated intraocular pressure during the early post-operative period and lower prevalence of glaucoma at the final visit, although this was not statistically significant. No such trends were seen in phakic eyes. Postoperative corneal curvature was significantly steeper in oversized than same-sized grafts, in both phakic and aphakic eyes; there was no difference in postoperative astigmatism. Anterior chamber depth was significantly greater in oversized grafts. Of four wound dehiscences, all occurred in same-sized grafts.