[Functional outcomes after penetrating keratoplasty in pseudoexfoliation syndrome (PEX)-keratopathy]

Keratopathy in pseudoexfoliation syndrome (PEX-keratopathy) is a particular form of corneal endothelial decompensation, which requires a penetrating keratoplasty (PK) for visual rehabilitation at advanced states. The aim of this study was to evaluate the functional outcome and the development of intraocular pressure (IOP) after PK in patients with PEX-keratopathy depending on the presence of pre-existing glaucoma.

This retrospective study included 21 eyes of 21 patients (age 78.6 +/- 7.5 years) with a mean postoperative follow-up of 1.8 +/- 2.2 (median 2) years. The diagnosis of PEX-keratopathy was confirmed clinically as well as by electron microscopy. The recipient and donor trephinations were performed from the epithelial side using an 193 nm excimer laser (n = 11) or mechanically (n = 10). An iridotomy was performed routinely during PK. The postoperative treatment with topical steroid was standardized.

Preoperatively, a secondary open-angle glaucoma (SOAG) with optic nerve damage was diagnosed in 11 patients (52 %). Topical antiglaucomatous treatment was needed in 81 % of patients with SOAG. Six weeks postoperatively, patients with SOAG showed a higher prevalence of increased intraocular pressure (IOP) and/or antiglaucomatous treatment compared to patients without SOAG (45 % vs. 20 %). Most of the mild-early intraocular pressure elevations were controlled in both groups during the follow-up. From one year post-PK, there was an increased need for topical antiglaucomatous treatment in both patient groups. In all eyes the IOP was controlled by topical antiglaucomatous treatment. Preoperatively, visual acuity was comparable in patients with and without SOAG (0.06 +/- 0.09 vs. 0.08 +/- 0.1, p = 0.7), but increased significantly more in patients without SOAG (0.38 +/- 0.1, median 0.4) than in patients with SOAG (0.2 +/- 0.1, median 0.2; p = 0.01) after PK. Visual acuity remained stable in both groups throughout the follow-up period. During follow-up only one eye developed an episode of reversible endothelial graft rejection 18 months postoperatively. An irreversible graft failure was seen in none of the patients.

The functional outcome after PK in PEX-keratopathy seems to be strongly associated with pre-existing SOAG. Patients without SOAG may expect good visual rehabilitation without persistent postoperative IOP increases. However, patients should be followed-up for a prolonged period of time, because from 1 year following PK the need for topical antiglaucomatous treatment increased significantly.