The influence of glaucoma history on graft survival after penetrating keratoplasty

Abstract

Background: It was the purpose of this retrospective study to evaluate the effect of a preoperative history of glaucoma on graft survival after penetrating keratoplasty.

Patients and methods: Six hundred and forty-six penetrating keratoplasties with generally good prognosis were analyzed retrospectively. Indications for surgery were corneal dystrophy, degeneration and scarring. Only first keratoplasties in corneas without severe vascularization or acute inflammation were included. Surface disorders, a history of herpes or Acanthamoeba keratitis were further exclusion criteria. Keratoplasties were performed only if glaucoma seemed to be controlled preoperatively. Graft survival ratios were calculated according to Kaplan and Meier, and statistical significance was evaluated by means of the log-rank test.

Results: With a glaucoma history the estimated 3-year graft survival rate was 71%, in contrast to 89% without such a history. This difference was statistically significant (P < 0.001). There was no difference between the groups with respect to immune reactions. With a glaucoma history, postoperative episodes of glaucoma decompensation were responsible for half of the graft failures.

Conclusions: A preoperative history of glaucoma affects graft prognosis negatively, presumably through a negative influence of postoperatively elevated intraocular pressure on a vulnerable graft endothelium, and not by an increase in immune reactions. Therefore, keratoplasties in eyes with glaucoma are high-risk procedures and glaucoma has to be monitored more efficiently pre- and postoperatively.