Identification of the preoperative and perioperative factors that predict postoperative endothelial cell density after Descemet membrane endothelial keratoplasty: A retrospective cohort study

Abstract

Low postoperative endothelial-cell density (ECD) plays a key role in graft failure after Descemet-membrane endothelial keratoplasty (DMEK). Identifying pre/perioperative factors that predict postoperative ECD could help improve DMEK outcomes. This retrospective study was conducted with consecutive adult patients with Fuchs-endothelial corneal dystrophy who underwent DMEK in 2015–2019 and were followed for 12 months. Patients underwent concomitant cataract surgery (triple-DMEK) or had previously undergone cataract surgery (pseudophakic-DMEK). Multivariate analyses assessed whether: patient age/sex; graft-donor age; preoperative ECD, mean keratometry, or visual acuity; triple DMEK; surgery duration; surgical difficulties; and need for rebubbling predicted 6- or 12-month ECD in the whole cohort or in subgroups with high/low ECD at 6 or 12 months. The subgroups were generated with the clinically relevant threshold of 1000 cells/mm2. Surgeries were defined as difficult if any part was not standard. In total, 103 eyes (95 patients; average age, 71 years; 62% women) were included. Eighteen eyes involved difficult surgery (14 difficult graft preparation or unfolding cases and four others). Regardless of how the study group was defined, the only pre/perioperative variable that associated significantly with 6- and 12-month ECD was difficult surgery (p = 0.01, 0.02, 0.05, and 0.0009). Difficult surgery also associated with longer surgery duration (p = 0.002). Difficult-surgery subgroup analysis showed that difficult graft dissection associated with lower postoperative ECD (p = 0.03). This association may reflect endothelial cell loss due to excessive graft handling and/or an intrinsic unhealthiness of the endothelial cells in the graft that conferred unwanted physical properties onto the graft that complicated its preparation/unfolding.

New forceps free injection technique for delivering descemet membrane endothelial keratoplasty preloaded endothelium-in grafts

“…Although we found a significant difference between baseline and follow-up ECD, however our patients showed a good mean cell density after the endothelial keratoplasty with a percentage of endothelial cell loss lower or comparable with what is described in literature. 11,15,[20][21][22][23][24] As expected, the number of cells at baseline significantly correlated with the ECD at follow-up. Considering that a DMEK graft loses up to 50% of cells during the first year of follow-up, clinicians should pay attention to donors' cell count when they performed the surgery in young patients.…”

Performance outcomes from a DMEK peeling and preparation wet lab

“…Our findings indicate a significantly reduced mortality of endothelial cells (TBPC) between the first and last attempts (p=0.01), serving as evidence for these benefits. Ultimately, a greater number of endothelial cells transplanted translate to enhanced graft performance and patient outcomes 24…”

“…Ultimately, a greater number of endothelial cells transplanted translate to enhanced graft performance and patient outcomes. 24 …”

“…Ultimately, a greater number of endothelial cells transplanted translate to enhanced graft performance and patient outcomes. 24 DMEK graft preparation's steep learning curve has profoundly hindered its widespread adoption. 6 Our data reveal that trainee surgeons become significantly quicker in performing the DMEK peel by their last attempt compared with their first.…”

Postoperative, but not preoperative, central corneal thickness correlates with the postoperative visual outcomes of Descemet membrane endothelial keratoplasty

“…All grafts had a requested ECD greater than 2200 cells/mm 2 . The following steps have been described in detail previously [22]. Thus, the graft was prepared by the microsurgeon in the operating room just before surgery, after which the patient's cornea was prepared for transplantation and the graft was injected into the anterior chamber.…”