Glaucoma in penetrating keratoplasty: risk factors, management and outcome

Abstract

Introduction: Glaucoma is a leading cause for graft failure. This retrospective study analyzes the risk factors, graft status, and treatment modalities in patients with post-penetrating keratoplasty glaucoma.

Methods: A retrospective analysis of case records of 1,848 penetrating keratoplasties carried out between 2000 and 2005 was performed. A total of 160 patients (160 eyes) with post-penetrating keratoplasty glaucoma were included; 112 cases were primary grafts, 48 repeated grafts. The assessment included the pre-operative history of corneal disease and glaucoma, the lens status, and the anesthesiological techniques. Furthermore, the response to anti-glaucoma treatment, graft failure, and endothelial cell loss was evaluated.

Results: The incidence of post-penetrating keratoplasty glaucoma was 8.7 % (160/1,848). Preoperative glaucoma was the most important risk factor (62/160). Half of the patients (81 patients) responded to medical therapy (51 %) and the other half of patients (79 patients) to surgical therapy (49 %); of the latter, filtering surgery were performed in 16 %, cyclodestructive procedures in 66 % and both in 16 %. One patient received a glaucoma implant and cyclodestructive procedures (1 %). After 24 months, clear grafts were achieved in 94 eyes (59 %). Visual acuity after 24 months of 20/200 (logMAR 1.0) or better was achieved in 77 eyes (46 %) and of 20/50 (logMAR 0.4) in 33 eyes (21 %).

Conclusions: Careful and ongoing observation of IOP, especially in the first year after PK, is recommended for patients after penetrating keratoplasty and prompt treatment of IOP elevation when indicated. Early filtering surgery with a better outcome than other surgery procedures should be preferred if medical treatment is not sufficient. Despite anti-glaucoma therapy, good visual outcome can remain beyond expectations despite a clear graft. While there is a potential option for graft exchange, damage to the optic nerve from end-stage glaucoma leads immutably to visual loss.