Prevention and Management of Pupil Block After Descemet Membrane Endothelial Keratoplasty.

Abstract

To assess frequency, associations, and outcomes of full air fill after Descemet membrane endothelial keratoplasty (DMEK). This retrospective study reviewed 368 consecutive DMEK cases performed to treat Fuchs dystrophy, bullous keratopathy, or failed keratoplasty. Primary outcomes were air bubble status, intraocular pressure, and incidence of pupil block and air reinjection. Using an air management algorithm, slit-lamp assessment 1 hour after DMEK identified complete air fill in 80/368 eyes (22%). This spontaneously resolved in 45 eyes. Air was removed from 35 eyes (9%). Eyes that required air removal were more likely to have occluded iridotomy than did eyes in which the full air fill spontaneously resolved (23% vs. 6.6%, respectively), P = 0.05. Although full air fill was more likely after DMEK combined with cataract surgery (P = 0.001), air removal was more likely after DMEK-only procedures (P = 0.01). Eyes that underwent air removal tended to have lower rebubble rates, although this did not reach statistical significance (P = 0.06). No cases of pupillary block glaucoma occurred, and full air fill did not significantly affect 6-month postoperative vision or endothelial cell density. A careful air management strategy successfully prevented pupil block in eyes that developed full air fill. DMEK-only procedures were more likely to require air removal than those combined with cataract surgery, which suggests that decreased zonular flexibility may prevent the air bubble from taking a more spherical shape and more easily allow occlusion of iridotomy.