THE INFLUENCE OF GLAUCOMA HISTORY ON GRAFT-SURVIVAL AFTER PENETRATINGKERATOPLASTY

Background: It was the purpose of this retrospective study to evaluate the effect of a preoperative history of glaucoma on graft survival af ter penetrating keratoplasty. Patients and methods: Six hundred and fo rty-six penetrating keratoplasties with generally good prognosis were analyzed retrospectively. Indications for surgery were corneal dystrop hy, degeneration and scarring. Only first keratoplasties in corneas wi thout severe vascularization or acute inflammation were included. Surf ace disorders, a history of herpes or Acanthamoeba keratitis were furt her exclusion criteria. Keratoplasties were performed only if glaucoma seemed to be controlled preoperatively. Graft survival ratios were ca lculated according to Kaplan and Meier, and statistical significance w as evaluated by means of the log-rank test. Results: With a glaucoma h istory the estimated 3-year graft survival rate was 71%, in contrast t o 89% without such a history. This difference was statistically signif icant (P < 0.001). There was no difference between the groups with res pect to immune reactions. With a glaucoma history, postoperative episo des of glaucoma decompensation were responsible for half of the graft failures. Conclusions: A preoperative history of glaucoma affects graf t prognosis negatively, presumably through a negative influence of pos toperatively elevated intraocular pressure on a vulnerable graft endot helium, and not by an increase in immune reactions. Therefore, keratop lasties in eyes with glaucoma are high-risk procedures and glaucoma ha s to be monitored more efficiently pre-and postoperatively.