Julia M. Weller

Clinical and ultrastructural characteristics of graft failure in DMEK: 1-year results after repeat DMEK.

Purpose: To evaluate the role of preexisting corneal pathology on the outcome of Descemet membrane endothelial keratoplasty (DMEK), and also to evaluate the long-term outcome of repeat DMEK for graft failure after primary DMEK. Methods: Eighteen patients undergoing repeat DMEK after failed DMEK were enrolled; 9 of 18 patients had successful primary DMEK on the fellow eye. Evaluations included preoperative anterior chamber depth, intraoperative degree of difficulty, transmission electron microscopy images (n = 14), best-corrected visual acuity (BCVA), endothelial cell density, central corneal thickness, corneal volume, and patient satisfaction. Results: Surgeries that led to graft failure had a higher intraoperative degree of difficulty compared with successful surgeries (P = 0.002). Eight of 14 failed grafts showed ultrastructural abnormalities, that is, inclusions or deposits of abnormal fibrillar material in Descemet membrane, indicating endothelial dysfunction before transplantation. BCVA on day 10 after surgery was worse in eyes with graft failure compared with successful DMEK (P = 0.008). Median BCVA (logarithm of the minimum angle of resolution) improved from 0.5 before DMEK and 1.9 before repeat DMEK to 0.3 at 1-year follow-up (P = 0.011). One year after repeat DMEK, endothelial cell density (cells/mm2) of donor corneas decreased from 2501 ± 264 to 1373 ± 270 (P < 0.001), central corneal thickness (µm) decreased from 807 ± 160 to 576 ± 178 (P = 0.002), and corneal volume (mm3) decreased from 84.1 ± 13.0 to 64.4 ± 12.5 (P = 0.002). Patient satisfaction showed no difference between primary and repeat DMEK. Conclusions: A preexisting subclinical corneal endothelial dysfunction may contribute to primary DMEK failure. Repeat DMEK can be performed safely with good long-term outcome.

Feasibility and Outcome of Descemet Membrane Endothelial Keratoplasty in Complex Anterior Segment and Vitreous Disease.

Purpose: Descemet membrane endothelial keratoplasty (DMEK) is becoming the method of choice for treating Fuchs endothelial dystrophy and pseudophakic bullous keratopathy. We investigated whether DMEK can serve as a routine procedure in endothelial decompensation even in complex preoperative situations. Methods: Of a total of 1184 DMEK surgeries, 24 consecutive eyes with endothelial decompensation and complex preoperative situations were retrospectively analyzed and divided into 5 groups: group 1: irido-corneo-endothelial syndrome (n = 3), group 2: aphakia, subluxated posterior chamber intraocular lens or anterior chamber intraocular lens (n = 6), group 3: DMEK after trabeculectomy (n = 4), group 4: DMEK with simultaneous intravitreal injection (n = 6), and group 5: DMEK after vitrectomy (n = 5). Main outcome parameters were best-corrected visual acuity, central corneal thickness, endothelial cell density, rebubbling rate, and graft failure rate. Results: Best-corrected visual acuity (logMAR) increased from 0.98 to 0.53 (P = 0.002), 0.53 (P = 0.091), and 0.57 (P = 0.203) after 1, 3, and 6 months, respectively. Central corneal thickness decreased from 731 ± 170 to 546 ± 152 &mgr;m (P = 0.001), 514 ± 66 &mgr;m (P = 0.932), and 554 ± 98 &mgr;m (P = 0.004) after 1, 3, and 6 months, respectively. Donor endothelial cell density decreased from 2478 ± 185 to 1454 ± 193/mm2 (P < 0.001), 1301 ± 298/mm2 (P = 0.241), and 1374 ± 261/mm2 (P = 0.213), after 1, 3, and 6 months, respectively. The rebubbling rate was 46% (11/24). Four patients (17%) had secondary graft failure. Conclusions: Our data provide evidence that DMEK is feasible for the treatment of endothelial decompensation in complex preoperative situations.

Anterior Chamber Air Bubble to Achieve Graft Attachment After DMEK: Is Bigger Always Better?

Purpose: To analyze the influence of the size of the air bubble subsequent to Descemet membrane endothelial keratoplasty (DMEK) surgery on the rate of graft detachment and need for rebubbling, the incidence of pupillary block, and the observed endothelial cell loss. Methods: This is a single-center, retrospective, consecutive case series of 74 cases undergoing DMEK and fulfilling the inclusion criteria concerning the size of the air bubble at the end of surgery. Based on the medical records, patients were divided into 2 groups (n = 37, respectively). The first group had an air bubble with a volume of approximately 50% and the second group of approximately 80% of the anterior chamber (AC) volume, respectively. Patients who did not comply with instructions to remain in the supine position until complete resorption of AC air or cases in which difficulties in graft preparation (eg, radial breaks) occurred were excluded from data analysis. The central corneal thickness and endothelial cell density were measured 6 months after surgery. Results: Ten of 37 patients (27.0%) in the 50% air bubble group and 3 of 37 patients (8.1%) in the 80% air bubble group needed 1 rebubbling procedure (P = 0.032). There was no difference between the groups after 6 months regarding endothelial cell density and central corneal thickness. No pupillary block was observed. Conclusions: Larger air bubbles of 80% anterior chamber volume decrease the risk of graft detachment after DMEK with no detrimental effect on the outcome and risk for pupillary block.

Unilateral retinitis pigmentosa: 30 years follow-up.

This case report depicts the clinical course of a female patient with unilateral retinitis pigmentosa (RP), who presented first in 1984 at the age of 43 years. At the beginning, there were cells in the vitreous leading to the diagnosis of uveitis with vasculitis. Within 30 years, the complete clinical manifestation of RP developed with bone spicule-shaped pigment deposits, pale optic disc, narrowed arterioles, cystoid macular oedema, posterior subcapsular cataract, concentric narrowing of the visual field and undetectable electroretinogram signal. At the age of 72 years, there are still no signs of retinal dystrophy in the other eye.

Larger Descemetorhexis to Improve Graft Adhesion in Descemet Membrane Endothelial Keratoplasty Does Not Cause Postoperative Peripheral Corneal Edema.

Purpose: To evaluate the incidence of peripheral corneal edema after Descemet membrane endothelial keratoplasty (DMEK) with respect to the size of the descemetorhexis. Methods: A single-center retrospective review of data of 200 consecutive DMEK surgeries for Fuchs endothelial dystrophy was performed. Forty-eight eyes of 47 patients were enrolled in this study based on the presence of a peripheral zone of free denuded stroma between the margin of the graft and the hosts Descemet membrane (DM) (group A) or a peripheral overlap between the graft and the hosts DM (group B). In group A (n=26 eyes), the diameter of the descemetorhexis was approximately 10 mm, whereas in group B (n=22 eyes), the diameter was approximately 6 mm. Both groups received an 8-mm graft. Main outcome measures included peripheral corneal thickness (PCT) at 4 mm from the center, central corneal thickness (CCT), central-to-peripheral thickness ratio (CPTR), and endothelial cell density (ECD). Results: Mean preoperative PCT±SD in group A was 728±52 &mgr;m and in group B was 708±49 &mgr;m (P=0.192). Four weeks after DMEK, mean PCT±SD was 703±43 &mgr;m in group A and 691±59 &mgr;m in group B (P=0.368). Mean preoperative CCT±SD was 642±53 &mgr;m and 627±58 &mgr;m in groups A and B, respectively (P=0.306). There was no significant difference in CCT between groups A and B 4 weeks after surgery (P=0.268). Mean preoperative CPTR±SD in group A was 0.88±0.05 and in group B was 0.89±0.05 (P=0.934). Four weeks after DMEK, CPTR was not significantly different between groups A and B (P=0.893). There was no significant difference in ECD between groups A and B, before and at 4 weeks after DMEK (P=0.093 and P=0.831, respectively). Conclusions: A larger descemetorhexis in DMEK resulting in a peripheral small zone of denuded stroma does not increase the incidence of peripheral corneal edema as compared with a small descemetorhexis with overlapping DMs.

Can we predict the refractive outcome after triple Descemet membrane endothelial keratoplasty

Purpose: To analyze and correlate corneal parameters with refractive shift after Descemet membrane endothelial keratoplasty combined with cataract surgery (triple Descemet membrane endothelial keratoplasty). Methods: This single-center retrospective observational case series included 152 eyes of 152 consecutive patients undergoing triple Descemet membrane endothelial keratoplasty in the first eye for Fuchs endothelial corneal dystrophy. Patients were examined preoperatively, as well as at 3, 6, and 12 months after surgery. The main outcome measures were: refractive shift (predicted refractive outcome based on intraocular lens calculation compared to actual postoperative refractive outcome), central corneal thickness, corneal volume, anterior and posterior corneal curvature, and corneal densitometry. These parameters were analyzed and correlated with the refractive shift after surgery. Results: After 3 months from surgery, a mean refractive shift of +1.12 ± 1.10 D was observed and remained stable until the last follow-up at 12 months (+1.24 ± 1.07 D). Correlation analysis showed a weak but significant positive correlation between refractive shift and preoperative posterior curvature (rho = 0.314; p = 0.002) or preoperative posterior densitometry (rho = 0.227; p = 0.008). No correlation was found between refractive shift and preoperative central corneal thickness, corneal volume, anterior curvature, or anterior/mid-cornea densitometry. Conclusion: Changes of the posterior cornea may have an influence on the refractive shift. Patients with flatter posterior corneal curvature or higher posterior corneal density seem to exhibit a higher hyperopic shift. The weak correlations indicate a poor predictive value of any preoperative parameter used in our study.

Air Versus Sulfur Hexafluoride Gas Tamponade in Descemet Membrane Endothelial Keratoplasty: A Fellow Eye Comparison

Purpose: To perform a fellow eye comparison of outcomes and complications when using air or sulfur hexafluoride (SF6) gas as a tamponade in Descemet membrane endothelial keratoplasty (DMEK). Methods: One hundred thirty-six eyes of 68 consecutive patients who underwent uneventful DMEK in both eyes for Fuchs endothelial corneal dystrophy were included in this retrospective study. Inclusion criteria were air tamponade (80% of the anterior chamber volume) in the first eye and 20% SF6 gas tamponade (80% of the anterior chamber volume) in the second eye; and same donor tissue culture condition in both eyes. All eyes received laser iridotomy on the day before DMEK. Main outcome measures included preoperative and postoperative best-corrected visual acuity, endothelial cell density, corneal volume, rebubbling rate, and rate of postoperative pupillary block caused by the air/gas bubble. Results: Thirteen of 68 eyes (19.1%) with an air tamponade needed rebubbling compared with 4 of 68 eyes (5.9%) with an SF6 gas tamponade (P = 0.036). Postoperative pupillary block necessitating partial release of air/gas occurred in 1 eye (1.5%) with an air tamponade and 3 eyes (4.4%) with an SF6 gas tamponade (P = 0.301). There were no significant differences in preoperative and postoperative best-corrected visual acuity, endothelial cell density, and corneal volume within 3-month follow-up. Conclusions: Our results confirm the previously reported better graft adhesion when using an SF6 gas tamponade in DMEK without increased endothelial cell toxicity. The rate of pupillary block in eyes with an SF6 gas tamponade was comparable to that with an air tamponade. As a consequence, we recommend using SF6 gas as the tamponade in DMEK.

“Bubble-in-the-Roll” Technique Using the Endoject DMEK Injector: Influence of the Air Bubble on Endothelial Cell Loss

Purpose: To evaluate the impact of the air bubble on endothelial cell loss using the “bubble-in-the-roll” technique during Descemet membrane endothelial keratoplasty (DMEK). Methods: Twenty DMEK grafts not suitable for transplantation were manually prepared from organ-cultured corneoscleral discs and injected into culture media using the Endoject DMEK injector (Medicel AG, Wolfhalden, Switzerland). Based on the injection method, the grafts were divided into 2 groups: In group A (n = 10), a small air bubble was placed inside the graft roll while it was in the injector. In group B (n = 10), the grafts were injected without an air bubble inside the graft roll. Main outcome measures included endothelial cell density (ECD) after graft stripping and graft injection. Results: There were no statistically significant differences between groups A and B in donor age, storage duration, and donor ECD. ECD decreased from 1929 ± 145 cells/mm2 to 1796 ± 303 cells/mm2 after graft stripping in group A and from 1801 ± 226 cells/mm2 to 1709 ± 290 cells/mm2 in group B. ECD after graft injection further decreased to 1683 ± 291 cells/mm2 in group A and to 1651 ± 292 cells/mm2 in group B. Endothelial cell loss after graft stripping and graft injection was not statistically significant between groups A and B (P = 0.29 and P = 1, respectively). Conclusions: The bubble-in-the-roll technique for injection and unfolding of the graft is a safe method for graft delivery into the anterior chamber guaranteeing orientation of the graft without harming the endothelium.