Risk Factors for Adjuvant Glaucoma Therapy and Graft Failure in DSAEK

Abstract

Purpose: To identify risk factors for escalation of medical and surgical glaucoma management and graft failure in DSAEK patients with and without pre-existing glaucoma, and to assess the association of escalation with graft failure or rejection.

Methods: In a retrospective cohort study, 194 DSAEK procedures performed by three surgeons over a five-year period were observed. Pre-existing glaucoma was defined as a known history of glaucoma or a history of elevated intraocular pressure (IOP) >22 that required medical or surgical treatment prior to DSAEK. Primary outcome variables included post-DSAEK IOP elevation and post-DSAEK escalation of medical management with eye drops. Secondary outcome variables included surgical management such as tube shunt or trabeculectomy after DSAEK, or graft failure.

Results: Of the 194 grafts, 71 eyes had pre-existing glaucoma and 123 without glaucoma. 31/71 (43.6%) eyes with pre-existing glaucoma required addition of glaucoma drops after DSAEK as compared to 23/123 (18.7%) eyes without pre-existing glaucoma (p<.0002). 11/71 (15.5%) eyes with pre-existing glaucoma required a tube postoperatively as compared to 1 eye without pre-existing glaucoma. No grafts with pre-existing tube shunt or trabeculectomy required additional glaucoma surgery after DSAEK. 20/194 (10.3%) grafts required triple procedure (cataract extraction, intraocular lens placement, and corneal transplant), which showed a significant association between requiring additional drops and having triple procedure (p < 0.0001). 14/194 (7.2%) grafts required “rebubble.” Of the 10/14 grafts with pre-existing glaucoma, 4 grafts failed (40%). And of the 4/14 grafts without pre-existing glaucoma, 2 grafts failed (20%).

Conclusions: Pre-operative glaucoma subjects had an almost 3-fold increase in odds of elevated IOP and 10-fold increase in odds of requiring additional glaucoma drops as compared to pre-operative non-glaucoma subjects. Triple procedure subjects had a 6.5-fold increase in odds of requiring additional eye drops as compared to subjects who did not receive triple procedure. None of the eyes with prior glaucoma surgery required surgical escalation within 24 months after DSAEK. Subjects with glaucoma had a greater risk of graft failure as compared to subjects without glaucoma. Subjects who required “rebubble” had a greater risk of graft failure as compared to subjects who did not require “rebubble.”

Keywords: 479 cornea: clinical science