Surgical outcomes of DSAEK in patients with prior Ahmed glaucoma drainage device placement

To study the surgical outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) in eyes with previous Ahmed glaucoma valve (AGV) implantation.

Retrospective chart review of all patients who underwent DSAEK by a single surgeon in the setting of prior AGV implantation between December 2009 and September 2011 with at least 12 months follow-up. Preoperative and postoperative endothelial cell counts, visual acuity, intraocular pressure, and glaucoma medications were recorded.

Eighteen eyes of 13 patients were included. The average endothelial cell count (cells/mm2) was 3087.7 (SD 390.8) preoperatively, 1974.3 (SD 646.0) at 6 months, 1831.7 (SD 851.2) at 12 months, and 1821.3 (SD 762.2) at 24 months. The average IOP (mm Hg) was 13.7 (SD 4.3) preoperatively, 15.1 (SD 5.0) at 6 months, 15.5 (SD 6.6) at 12 months, and 15.1 (SD 4.8) at 24 months. Average visual acuity (VA) preoperatively was 20/100 (logMAR 0.73, SD 0.27) and average best VA postoperatively was 20/60 (logMAR 0.5, SD 0.27). Nine of the 18 eyes (50%) had failed DSAEK grafts at 9.3 (SD 6.0) months. Six of these eyes had peripheral anterior synechiae (PAS) preoperatively, 3 had a history of uveitis, and 4 failures had multiple AGVs. Intraocular pressure control (<21 mm Hg) was maintained without additional medications in 11 eyes (61%) and with additional medication in 4 eyes (22%). Intraocular pressure control was not maintained in 3 eyes (17%).

Though challenging, DSAEK surgery can be successful in the setting of previous AGV implantation, with success rates comparable to those of penetrating keratoplasty in the same population. Higher failure rate of DSAEK with prior AGV appears to be associated with the presence of chronic angle closure glaucoma with 360-degree PAS with shallow chambers, the presence of multiple AGVs, and presence of uveitis.