Descemet Membrane Endothelial Keratoplasty in Corneal Endothelial Decompensation After a Forceps-Induced Corneal Birth Injury: Case Series and Technique.

PURPOSE: The aim of this study was to describe the efficacy of Descemet membrane endothelial keratoplasty (DMEK) in patients with corneal endothelial decompensation secondary to a forceps-induced corneal birth injury. METHODS: This was a retrospective, noncomparative, interventional case series. Four eyes of 4 patients (1 female and 3 males; mean age, 64.0 ± 4.7 years) with corneal endothelial decompensation due to forceps-induced corneal birth injury were included. DMEK was performed in all cases, using a combined technique, including the use of intraoperative optical coherence tomography, vital staining of Descemet membrane of both host and donor, removal of scarred Descemet membrane with side-port forceps and vitreous cutter to smoothen the posterior corneal surface, epithelial peeling, and illumination for visualization. The examination included preoperative and postoperative ophthalmologic examinations: best-corrected visual acuity (converted to logarithm of the minimum angle of resolution [logMAR]), intraocular pressure, endothelial cell density (ECD), and central corneal thickness. RESULTS: No postoperative complications were noted, and corneal transparency was maintained during follow-up (mean follow-up period, 32.0 ± 27.0 months; range, 3-71 months). The mean best-corrected visual acuity was 0.52 ± 0.35 logMAR preoperatively and 0.15 ± 0.09 logMAR at the last visit. The mean postoperative ECD was 1632 ± 631 cells/mm2 (mean ECD at baseline, 3167 cells/mm2). Central corneal thickness decreased from 640 ± 67 µm preoperatively to 576 ± 58 µm postoperatively. CONCLUSIONS: This study suggests that DMEK can be performed uneventfully in eyes with a forceps-induced corneal birth injury. The combination of surgical techniques may be an effective approach for DMEK.

Incidence of Graft Rejection in Descemet Membrane Endothelial Keratoplasty After COVID-19 mRNA Vaccination.

PURPOSE: The aim of this study was to investigate the Descemet membrane endothelial keratoplasty (DMEK) rejection rate after COVID-19 vaccination with an mRNA vaccine. METHODS: This was a multicenter, retrospective cohort study. A total of 198 patients who underwent DMEK between January 2006 and December 2020 were divided into 2 cohorts: consecutive patients who received at least 1 COVID-19 vaccination in 2021 (vaccination started from February 2021 in Japan) and nonvaccinated patients (control cohort). Patients who had a postoperative observation period of less than 90 days were excluded. The main outcome measurement was the incidence of graft rejection. A Cox proportional hazards regression model was used for comparisons with the nonvaccinated group. RESULTS: Six rejection episodes were observed in 198 patients (124 nonvaccinated and 74 vaccinated patients), with 1 occurring in the nonvaccinated group and 5 in the vaccinated group. In the univariate model, vaccination had a significant effect on rejection episodes ( P = 0.003). The effect of vaccination was also significant ( P = 0.004) after adjusting for covariates. CONCLUSIONS: This study suggests that there may be a higher rejection rate after COVID-19 vaccination in patients who underwent DMEK. Patients should be warned of the rejection risk and its typical symptoms before receiving an mRNA COVID-19 vaccine, although further larger studies are needed to confirm the involvement of vaccination.

Evaluation of corneal nerves and dendritic cells by in vivo confocal microscopy after Descemet's membrane keratoplasty for bullous keratopathy.

This study evaluated changes in corneal nerves and the number of dendritic cells (DCs) in corneal basal epithelium following Descemet membrane endothelial keratoplasty (DMEK) surgery for bullous keratopathy (BK). Twenty-three eyes from 16 consecutive patients that underwent DMEK for BK were included. Eyes of age-matched patients that underwent pre-cataract surgery (12 eyes) were used as controls. In vivo confocal microscopy was performed pre- and postoperatively at 6, 12, and 24 months. Corneal nerve length, corneal nerve trunks, number of branches, and the number of DCs were determined. The total corneal nerve length of 1634.7 ± 1389.1 µm/mm2 before surgery was significantly increased in a time-dependent manner to 4485.8 ± 1403.7 µm/mm2, 6949.5 ± 1477.1 µm/mm2, and 9389.2 ± 2302.2 µm/mm2 at 6, 12, and 24 months after DMEK surgery, respectively. The DC density in BK cornea pre- and postoperatively at 6 months was significantly higher than in the controls, and decreased postoperatively at 12 and 24 months and was significantly lower than that at 6 months postoperatively. Thus, our results suggest that DMEK can repair and normalize the corneal environment.

COMPARISON OF THE RETINAL BLOOD FLOW VELOCITY BETWEEN LASER SPECKLE FLOWGRAPHY AND THE RETINAL FUNCTION IMAGER.

PURPOSE: To compare the retinal blood flow velocity using laser speckle flowgraphy (LSFG) and a retinal function imager (RFI) in healthy Japanese subjects. METHODS: This study included a total of 15 eyes of 15 healthy Japanese subjects (mean age, 41.7 ± 17.0 years). The retinal blood flow velocities were separately measured in arteries and veins around the optic disc using LSFG and an RFI. Linear regression analyses were used to analyze possible correlations of retinal blood flow velocities between the devices. RESULTS: The average blood flow velocities using LSFG as the mean blur rate were 18.6 ± 4.8 in arteries and 18.3 ± 5.5 in veins. The average blood flow velocities using the RFI were 3.4 ± 1.1 mm/second in arteries and 2.9 ± 0.9 mm/second in veins. Although retinal blood flow velocities in arteries and veins using LSFG were nearly the same, there were statistical differences in retinal blood flow velocities between arteries and veins using the RFI (P = 0.701 using LSFG, P = 0.041 using the RFI). Significant correlations were found between LSFG and the RFI in arteries and veins (all, P < 0.001). CONCLUSION: There were strong positive correlations in retinal blood flow velocities between LSFG and the RFI in healthy subjects.