Descemet membrane endothelial keratoplasty: learning curve of a single surgeon

Abstract

Purpose: To evaluate the learning curve of standardized "no-touch" Descemet membrane endothelial keratoplasty (DMEK) of a single surgeon in a clinic without an in-house eye bank facility.

Methods: For 25 eyes of 22 patients, Descemet graft preparation and DMEK surgery were performed according to the protocols of the Netherlands Institute for Innovative Ocular Surgery with minor modifications. Best spectacle-corrected visual acuity, subjective refraction, Scheimpflug tomography, and endothelial cell density of the donor tissue were documented before and at 1, 3, and 6 months after the surgery; intraoperative and postoperative complications were recorded.

Results: No donor tissue was lost owing to preparation failure of the Descemet graft allowing all surgeries to be completed as planned. At 6 months after the surgery, 83% of eyes reached ≥ 20/40 (≥ 0.5), 48% ≥ 20/28 (≥ 0.8), and 30% (7/23) ≥ 20/20 (≥ 1.0) (n = 23). The mean change in both spherical equivalent and refractive cylinder in the same interval was minimal (0.03 diopter). Mean donor endothelial cell density decreased from 2444 cells per square millimeter (± 198 cells/mm2) before the surgery to 1331 cells per square millimeter (± 491 cells/mm2) at 6 months after the surgery. Partial graft detachment requiring rebubbling occurred in 9 cases (36%). One eye developed primary graft failure.

Conclusions: This case series shows that DMEK by a beginning surgeon can achieve good results without preparing the graft in an eye bank. Use of backup tissue can be avoided by strictly adhering to the Netherlands Institute for Innovative Ocular Surgery techniques and by harvesting the graft the day before surgery to avoid last-minute cancellation.