Intrastromal Descemet Membrane Transplantation as a Potential Alternative to Bowman Layer Inlays in Eyes With Advanced Keratoconus.

ABSTRACT: Herein, we report the outcomes of intrastromal Descemet membrane (DM) transplantation in corneas with advanced keratoconus. Three eyes (three patients) showed advanced keratoconus. No eye underwent prior UV-cross-linking or any other ocular surgery. In all eyes, A donor DM was implanted into a mid-stromal pocket and clinical outcomes were evaluated up to 24 months after surgery. All procedures were uneventful. Up to 24 months postoperatively, the DM graft was well-positioned and barely visible within the recipient stroma; all corneas were clear. No eye showed signs of keratoconus progression throughout the follow-up. No changes were observed in uncorrected and best contact lens corrected visual acuity, central endothelial cell density, corneal thinnest point pachymetry, and maximum keratometry values. No early or late postoperative complications were observed. Intrastromal DM transplantation may be an alternative to intrastromal Bowman layer transplantation in advanced keratoconus, to postpone deep anterior lamellar or penetrating keratoplasty.

Three-quarter DMEK in eyes with glaucoma draining devices to avoid secondary graft failure.

PURPOSE: To present a case series of a modified three-quarter Descemet's membrane endothelial keratoplasty (3/4-DMEK) technique to treat pseudophakic bullous keratopathy in the presence of a glaucoma drainage device (GDD) tube in the anterior chamber by reducing the risk of donor endothelial damage due to absence of donor endothelial cells overlying the GGD tube area. METHODS: In this prospective case series, four eyes of three patients with stable glaucoma underwent 3/4-DMEK surgery for pseudophakic bullous keratopathy after GDD insertion. The patients were followed up to 24 ± 2.5 months postoperatively. RESULTS: No intraoperative or postoperative complications were noted. The average central endothelial cell density (ECD) was 1093 ± 74 cells/mm2 at 12 months postoperatively, corresponding to an ECD decrease of 58 (±6)% as compared to preoperative values. Average best-corrected visual acuity increased from finger counting before surgery to 20/60 (logMar 0.5) at 12 months after 3/4-DMEK and remained stable up to 24 months postoperatively. All corneas remained clear at the last available follow-up. CONCLUSION: This case series demonstrates the technical feasibility of 3/4-DMEK in eyes with pseudophakic bullous keratopathy in the presence of a GDD tube. The absence of a donor DM and donor cells above the silicone tube excludes direct tube contact with the graft. Longer term studies are needed to show the effect of this modified graft pattern and dimensions on transplant survival.

Five Keratoplasties From One Donor Cornea.

PURPOSE: To describe the feasibility of same-day, consecutive use of a single donor cornea in 5 patients with corneal pathology, who required anterior lamellar and endothelial keratoplasties. METHODS: Descemet membrane (DM) with endothelium was completely stripped from a single corneoscleral button and punched out from the endothelial side with a circular, standard punch. Using a custom-made punch for linear cutting of DM, we obtained 4 quarter-grafts (Q-graft). The denuded and punched-out corneal stroma was transplanted in 1 patient with keratoconus, using the big-bubble deep anterior lamellar keratoplasty (DALK) technique. The 4 DM Q-grafts were consecutively transplanted to 4 patients with Fuchs dystrophy using the quarter Descemet membrane endothelial keratoplasty (Q-DMEK or 1/4 DMEK) technique. RESULTS: All surgical procedures were performed successfully during 1 surgical session. No intraoperative or postoperative complications requiring intervention were observed. Six months after surgery, the decimal best-corrected visual acuity achieved was 0.66 after DALK and 0.95 ± 0.1 (range, 0.8-1.0) in the 4 Q-DMEK cases; the endothelial cell density was 1680 ± 254 cells/mm (range, 1492-2039 cells/mm). Six months postoperatively, all corneas were clear. CONCLUSIONS: In this limited series, we demonstrate that 1 donor cornea can be successfully used for 5 recipients. Although performing DALK and Q-DMEK on a single day is technically challenging, it is feasible and can dramatically reduce the shortage and the cost of corneal tissue. Strict case selection is necessary. Further study on this approach is required.

A case of severe corneal flattening after Descemet stripping endothelial keratoplasty.

PURPOSE: To report a case of extreme corneal flattening after initially uneventful Descemet stripping endothelial keratoplasty (DSEK). METHODS: A 76-year-old man underwent uneventful DSEK for pseudophakic bullous keratopathy (PBK) in his left eye. Postoperative evaluations were performed using anterior segment optical coherence tomography and biomicroscopy. RESULTS: The DSEK graft showed full adherence to the host stroma. Two weeks after surgery, the transplanted cornea developed pronounced flattening of the central corneal curvature accompanied by graft folds and remained unchanged until the most recent follow-up 20 weeks after surgery. CONCLUSIONS: Severe corneal flattening may be an undescribed complication occurring after uneventful DSEK, without any concomitant ocular pathology or detectable cause.

Multicenter study of descemet membrane endothelial keratoplasty: first case series of 18 surgeons.

IMPORTANCE: 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 (≥0.5), 117 (42.5%) at least 20/25 (≥0.8), and 61 (22.2%) at least 20/20 (≥1.0). 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.