Purpose: To determine the prevalence and risk factors for escalation of glaucoma therapy after penetrating keratoplasty (PK) and its impact on graft survival and visual outcome.
Design: Retrospective case series.
Participants: Seven hundred fifteen consecutive eyes of 678 patients undergoing PK.
Methods: Retrospective review of every case of PK performed at King Khaled Eye Specialist Hospital between January 1, 2001 and December 31, 2002.
Main outcome measures: Escalation of glaucoma therapy, graft survival, and visual outcome.
Results: Escalation of glaucoma therapy occurred in 89 (12.4%) eyes of 715 PK procedures during a mean follow-up of 32.2 months. Medical escalation accounted for 73 (82.0%) cases, whereas surgical escalation occurred in 16 (18.0%) eyes. The following were significantly associated with an increased risk of escalation of glaucoma therapy: surgical indication for PK (P<0.001), increasing patient age (P<0.001), preexisting glaucoma (P<0.001), recipient trephination < 7.0 mm (P = 0.02), and pseudophakia or aphakia (P<0.001). Eyes with escalation of glaucoma therapy had significant reduction in graft survival compared with eyes in which this did not occur (52.8% vs. 82.9%, P<0.001). Escalation of glaucoma therapy was associated with a significant reduction in the percentage of eyes achieving visual acuity of 20/40 or better (9.0% vs. 42.1%, P<0.001) and a significant increase in those obtaining 20/200 or worse (70.8% vs. 26.7%, P<0.001).
Conclusions: Escalation of glaucoma therapy is a serious sequela of PK that is significantly associated with an increased risk of graft failure and poor visual outcome.