Multicenter Study of Descemet Membrane Endothelial Keratoplasty

Abstract

Surgeons starting to perform Descemet membrane endothelial keratoplasty (DMEK) should be informed about the learning curve and experience of others. OBJECTIVE To document the clinical outcome of standardized "no-touch" DMEK and its complications during the learning curves of experienced surgeons. DESIGN, SETTING, AND PARTICIPANTS Retrospective multicenter study. A total of 431 eyes from 401 patients with Fuchs endothelial dystrophy (68.2%) and bullous keratopathy (31.8%) underwent DMEK performed by 18 surgeons in 11 countries. EXPOSURES Descemet membrane endothelial keratoplasty. MAIN OUTCOMES AND MEASURES Best-corrected visual acuity (BCVA), endothelial cell density, and intraoperative and postoperative complications. RESULTS Of 275 eyes available for BCVA pooled analysis, BCVA improved in 258 eyes (93.8%), remained unchanged in 12 (4.4%), and deteriorated in 5 (1.8%). Two hundred seventeen eyes (78.9%) reached a BCVA of at least 20/40 (Ն0.5), 117 (42.5%) at least 20/25 (Ն0.8), and 61 (22.2%) at least 20/20 (Ն1.0). Eyes with at least 6 months of follow-up (n = 176) reached similar BCVA outcomes. Mean (SD) decrease in endothelial cell density at 6 months was 47% (20%) (n = 133 [P = .02]). Intraoperative complications were rare, including difficulties in inserting, unfolding, or positioning of the graft (1.2%) and intraoperative hemorrhage (0.5%). The main postoperative complication was graft detachment (34.6%); 20.4% underwent a single rebubbling procedure, occasionally requiring a second (2.6%) and a third rebubbling (0.7%), and 17.6% underwent a second keratoplasty.CONCLUSIONS AND RELEVANCE Our multicenter study showed that the standardized no-touch DMEK technique was feasible in most hands. The main challenges for surgeons starting to perform the procedure may be (1) to decide whether graft preparation is outsourced or performed during surgery, (2) to limit the number of graft detachments and secondary procedures, and (3) to obtain organ cultured donor corneal tissue.

Comparison of 20% sulfur hexafluoride with air for intraocular tamponade in Descemet membrane endothelial keratoplasty (DMEK)

“…Detachment rates reported in the literature vary, with one recent multicenter study reporting rates of 34.6% (6) .…”

“…Although some surgeons use air for tamponade during the procedure, longer-acting inert gases, such as sulfur hexafluoride (SF 6 ), have been explored for this application recently. SF 6 has a higher buoyancy and a longer half-life than those of air (7) , which possibly provides advantages for maintaining graft attachment postoperatively.…”

“…SF 6 has a higher buoyancy and a longer half-life than those of air (7) , which possibly provides advantages for maintaining graft attachment postoperatively. A recent study of 44 patients who underwent DSEK compared SF 6 with air for graft attachment and noted that, although patients who received air had five graft detachments, there were no detachments reported in the group that received SF 6 (8) . Additionally, Guell et al, recently demonstrated reduced detachment rates with SF 6 from those with air in their series, and no effect on corneal endothelial cell counts was observed (9) .…”

“…at the Wilmer Eye Institute of Johns Hopkins Hospital between January 2012 and De cember 2014. Forty-two eyes were identified; 21 received air for intraocular tamponade and 21 received SF 6 . Approval from the Institutional Review Board of Johns Hopkins University was obtained, and the study was conducted in concordance with the ethical principles established in the Declaration of Helsinki.…”

“…Following a 10-minute waiting period, a small amount of gas was released to reduce the IOP to approximately 10-20 mmHg by palpation. The patient was then discharged home and instructed to remain in the supine position as follows: for air, the supine period was continuous until 6 pm on postoperative day 2 and included 10-minute upright periods hourly while awake and every 2 hours overnight on the night of surgery only; for SF 6 , the supine period was continuous for the day of surgery and postoperative day 1 and included 10-minute upright periods hourly while awake and every 2-3 hours overnight on the night of surgery and the next night. For postoperative days 2 and 3, 2 hours of supine positioning were interspersed with 1 hour of upright light activity and no overnight positioning, and for postoperative days 4 and 5, 2 hours of supine positioning were interspersed with 2 hours of upright light activity and no overnight positioning.…”