Congenital Corneal Staphyloma: A Comprehensive Histopathologic Assessment Including Associated Anterior Segment Abnormalities.

Congenital corneal staphyloma is a rare congenital malformation with guarded visual potential. The cornea is opaque, markedly ectatic, and lined by uveal tissue with a variety of associated anterior segment abnormalities. In this case report, the detailed histopathology of this condition is highlighted with an unusual finding of the malformed lens. [J Pediatr Ophthalmol Strabismus. 2024;61(3):e28-e32.].

In Vivo Assessment of Retinal Phenotypes in Axenfeld-Rieger Syndrome.

Purpose: Axenfeld-Rieger syndrome (ARS) is characterized by ocular anomalies including posterior embryotoxon, iridocorneal adhesions, corectopia/iris hypoplasia, and developmental glaucoma. Although anterior segment defects and glaucoma contribute to decreased visual acuity, the role of potential posterior segment abnormalities has not been explored. We used high-resolution retinal imaging to test the hypothesis that individuals with ARS have posterior segment pathology. Methods: Three individuals with FOXC1-ARS and 10 with PITX2-ARS completed slit-lamp and fundus photography, optical coherence tomography (OCT), OCT angiography, and adaptive optics scanning light ophthalmoscopy (AOSLO). Quantitative metrics were compared to previously published values for individuals with normal vision. Results: All individuals demonstrated typical anterior segment phenotypes. Average ganglion cell and inner plexiform layer thickness was lower in PITX2-ARS, consistent with the glaucoma history in this group. A novel phenotype of foveal hypoplasia was noted in 40% of individuals with PITX2-ARS (but none with FOXC1-ARS). Moreover, the depth and volume of the foveal pit were significantly lower in PITX2-ARS compared to normal controls, even excluding individuals with foveal hypoplasia. Analysis of known foveal hypoplasia genes failed to identify an alternative explanation. Foveal cone density was decreased in one individual with foveal hypoplasia and normal in six without foveal hypoplasia. Two individuals (one from each group) demonstrated non-foveal retinal irregularities with regions of photoreceptor anomalies on OCT and AOSLO. Conclusions: These findings implicate PITX2 in the development of the posterior segment, particularly the fovea, in humans. The identified posterior segment phenotypes may contribute to visual acuity deficits in individuals with PITX2-ARS.

Quality assurance in corneal transplants: Donor cornea assessment and oversight.

The cornea is the most frequently transplanted human tissue, and corneal transplantation represents the most successful allogeneic transplant worldwide. In order to obtain good surgical outcome and visual rehabilitation and to ensure the safety of the recipient, accurate screening of donors and donor tissues is necessary throughout the process. This mitigates the risks of transmission to the recipient, including infectious diseases and environmental contaminants, and ensures high optical and functional quality of the tissues. The process can be divided into 3 stages: (1) donor evaluation and selection before tissue harvest performed by the retrieval team, (2) tissue analysis during the storage phase conducted by the eye bank technicians after the retrieval, and, (3) tissue quality checks undertaken by the surgeons in the operating room before transplantation. Although process improvements over the years have greatly enhanced safety, quality, and outcome of the corneal transplants, a lack of standardization between centers during certain phases of the process still remains, and may impact on the quality and number of transplanted corneas. Here we detail the donor screening process for the retrieval teams, eye bank operators. and ophthalmic surgeons and examine the limitations associated with each of these stages.

Repeatability and agreement between a reference Scheimpflug tomographer and a low-cost Scheimpflug system.

PURPOSE: To assess the repeatability and agreement between Scheimpflug-based corneal topographers, Scansys and Pentacam, in measuring ocular parameters in myopic eyes. SETTING: Grade-A tertiary hospital in Beijing, China. DESIGN: Cross-sectional study. METHODS: The following measurements were performed in 204 subjects undergoing preoperative examinations for refractive surgery from the corneal curvature, astigmatism, corneal thickness, corneal volume, corneal asphericity, anterior chamber depth (ACD) and volume (ACV), and pupil diameters. Repeatability was determined using intraclass correlation coefficient with 95% CI, Cronbach α, coefficient of variation, within-subject SD, test-retest repeatability, and 1-way analysis of variance (1-way analysis of variance). The interdevice agreement was determined using paired t test and Bland-Altman plots. RESULTS: Scansys showed good repeatability in the anterior and posterior corneal flattest meridian (Kf), steepest meridian (Ks), and mean (Km); axis of anterior corneal Ks; anterior corneal astigmatism; pupil central corneal thickness (CCT); CCT; corneal apex thickness; thinnest corneal thickness; corneal volume; photopic pupil diameter; ACD; and ACV. In the agreement study, Bland-Altman plots showed that 95% limit of agreement of corneal curvature, pupil CCT, corneal apex thickness, thinnest corneal thickness, and corneal volume generated by Scansys and Pentacam were narrow. There were no statistically significant differences in the anterior corneal Kf and Km. CONCLUSIONS: Scansys showed good repeatability in measuring corneal curvature of anterior and posterior surfaces, anterior corneal astigmatism, corneal thickness, corneal volume, photopic pupil diameter, ACV, and ACD. Scansys and Pentacam can only be used interchangeably in measuring anterior corneal curvature.

Economic appraisal of prosthetic replacement of ocular surface ecosystem in Canada.

OBJECTIVE: To perform an economic appraisal of the Prosthetic Replacement of Ocular Surface Ecosystem (PROSE; BostonSight, Needham Heights, Mass.) lens in patients with a distorted corneal surface or ocular surface disease in Canada. DESIGN: Retrospective observational cohort study with cost, cost-utility, and benefit-cost analyses. PARTICIPANTS: Patients who received PROSE from the only PROSE clinic in Canada from 2018 to 2020. METHODS: Visual acuity (VA) outcomes of the participants were assessed. Benefits were defined as VA improvements that were converted into utilities and then quality-adjusted life years. Economic values were derived via government statements, clinic financial statements, and published literature. RESULTS: Average best-corrected VA (BCVA) improvement was -0.42 ± 0.41 logMAR (p = 2.68 × 10-13) or Snellen 20/53 for the overall cohort, -0.51 ± 0.48 (p = 5.42 × 10-8) or Snellen 20/65 for distorted corneal surface patients, and -0.31 ± 0.30 (p = 1.30 × 10-7) or Snellen 20/41 for ocular surface disease patients. This corresponded to discounted quality-adjusted life year gains of 0.51, 0.65, and 0.42, respectively, over an estimated 5-year PROSE device lifespan. Average cost to fit a patient with PROSE was USD$5 469.85 (CAD$7 087.28), of which USD$4 971.38 (CAD$6 441.42) was clinic cost and USD$498.47 (CAD$645.87) was patient cost. Cost-utility was USD$10 256.47 (CAD$13 289.31) for the overall cohort, USD$8 439.79 (CAD$10 935.44) for distorted corneal surface patients, and US$13 069.90 (CAD$16 934.67) for ocular surface disease patients. The benefit-cost ratio was 34.4 for all, 43.8 for distorted corneal surface patients, and 28.3 for ocular surface disease patients. CONCLUSIONS: Our economic appraisal demonstrated that PROSE treatment provides a significant, cost-effective benefit to Canadian patients with distorted corneal surfaces and ocular surface diseases. This indicates that PROSE clinics are an efficient investment.

Assessment of corneal and limbal epithelial thickness by spectral-domain optical coherence tomography in brachycephalic and non-brachycephalic dogs.

OBJECTIVE: To investigate the variance in corneal epithelial thickness (CET) and limbal epithelial thickness (LET) according to the age and skull type by using spectral-domain optical coherence tomography (SD-OCT) in normal dogs. ANIMALS AND PROCEDURES: This study used an eye each from 46 dogs (24 brachycephalic and 22 non-brachycephalic dogs) assessed to have clear corneas. Each dog was classified according to age into groups 1 (0-5 years), 2 (6-10 years), and 3 (>11 years). OCT imaging was performed on the central cornea for CET and perpendicular to the quadrant of the limbus for LET. The average of the maximum LET (maxLET) value was measured in four eye quadrants. RESULTS: Corneal epithelial thickness was not significantly different according to age in brachycephalic and non-brachycephalic dogs. Visualization of the limbal invagination was better when the maxLET was thick. Nasal and temporal maxLETs were significantly thicker than superior and inferior maxLETs in non-brachycephalic dogs. In brachycephalic dogs, there was a significant decrease in nasal maxLET with age (rs  = -0.489, p = .015). Significant differences between brachycephalic and non-brachycephalic dogs were observed in nasal maxLET (p = .024) and temporal maxLET (p = .011). CONCLUSIONS: Invagination was better visualized in the nasal and temporal limbal quadrants of non-brachycephalic dogs compared with brachycephalic dogs, and the maxLETs of the regions were thicker than those of the brachycephalic dogs. CET and LET measurements using SD-OCT can help in clinical assessment and research on ocular surface diseases in dogs.

Application of data mining algorithms to study data trends for corneal transplantation.

PURPOSE: To utilize data mining for analysis of corneal transplantations (CT) in Florida from 2005-2014, segmented by demographics, geography, and transplantation technique. METHODS: A retrospective, database study was performed utilizing data queried from the Healthcare and Cost Utilization Project using Current Procedural Terminology codes for lamellar keratoplasty (ALK), endothelial keratoplasty (EK), and penetrating keratoplasty (PKP). Payer status, ethnic group, age, gender, and geography (urban versus rural) was extracted from each surgical encounter and reconfigured to provide a "clean", congruous dataset for statistical analysis. This Institutional Review Board-approved study did not utilize identifiable patient information; thus, individual informed consent was not required. RESULTS: From 2005-2014, CT (n=28,607) represented less than 1% of the total ambulatory surgeries (n=12,695,932) performed in Florida. EK volume increased while PKP and ALK volume decreased, year-over-year. Statistical significance was found between transplantation technique by sex (P<0.001) and ethnic group (P<0.001). The largest sex discrepancy was EK (59% female, 41% male). White patients underwent relatively fewer PKP than EK (71% vs. 83% of totals), while Black patients underwent relatively more PKP than EK (14% vs 6% of totals). Statistical significance was found between techniques by payer (P<0.001). Medicare was the most common payer for all techniques, but ALK and PKP had higher percentages of private insurance and self-pay. No statistical significance was found between techniques by geographic location. Corneal edema (22.4%), endothelial dystrophy (17.5%), and bullous keratopathy (10.9%) were erroneously coded as indications for ALK. Corneal scars (2.5%) and corneal opacity (1.7%) were erroneously coded as indications for EK. CONCLUSIONS: CT rates in Florida appear to overrepresent the female sex and underrepresent ethnic minorities, with propensities between PKP and African Americans, EK and female patients, and EK and Medicare reimbursement. Our study further confirms the utility of data mining for providing efficient, detailed, and practical insights into ophthalmology procedures, while highlighting the intrinsic challenges of large datasets.

Effectiveness of a Tele-Ophthalmology Vision Center in Treating Corneal Disorders and Its Associated Economic Benefits.

PURPOSE: The aim of this study was to study the clinical and economic impact of a teleophthalmology-based vision center (VC) in the management of corneal diseases in rural south India. METHODS: Data of patients with corneal disorders who visited the VC in the year 2019 were analyzed for the total number of outpatient visits, the proportion of corneal cases that were treated at the VC, those referred to the base hospital (BH), and the costs of treatment. RESULTS: In 2019, 1131 (10%) of 10,850 patients who visited the VC were diagnosed with corneal disorders. Of these, 950 (84%) patients were treated at the VC itself and did not require to be referred. The remaining 181 (16%) were referred to the BH. Of these 1131 patients, 836 (74%) patients presented with a painful acute corneal disorder. The most common painful acute corneal disorders included corneal foreign body (376, 33%), epithelial abrasions (205, 18%), and infectious keratitis (124, 11%). A patient can save approximately a minimum of INR 1200 (USD 16) by attending the VC rather than the BH. In 2019, by treating 950 patients, the VC saved approximately INR 114,0000 (USD 15,200) for the community. A similar calculation extrapolated to a 10-year period (2009-2019) revealed that by providing care for these corneal disorders at the community level, the VC saved approximately INR 705,8400 (USD 94,112) for the community. CONCLUSIONS: VC reduces the barriers to care by increasing the accessibility and affordability of treatment for patients with corneal disorders, resulting in a significant cost saving to the community.

Economic, clinical and social impact of simple limbal epithelial transplantation for limbal stem cell deficiency.

AIMS: To report the global uptake of simple limbal epithelial transplantation (SLET) and compare the economic, clinical and social outcomes of SLET with those of cultured limbal epithelial transplantation (CLET). METHODS: A comprehensive literature review and an online survey of eye surgeons were conducted to understand the efficacy and current uptake of SLET surgery. A de novo economic model was developed to estimate the cost savings with SLET compared with CLET. Our economic analysis is conducted from an Indian perspective, as this is where the technique originated. A scenario analysis using the UK cost data and a user-friendly Excel model is included to allow users to input the costs from their setting to estimate the cost savings with using SLET compared with using CLET RESULTS: The anatomical success with SLET in adults (72.6% (range 62%-80%)) was the same as CLET (70.4% (range 68%-80.9%)). For children, the outcome for SLET (77.8% (range 73%-83%)) was better than with CLET (44.5% (range 43%-45%)). In response to our informal questionnaire, 99 surgeons reported to have performed SLET on 1174 patients in total. They appreciated that SLET negates the requirement for costly tissue engineering facilities. Results of economic analysis suggested that SLET provided an estimated cost-savings of US$6470.88 for adults and US$6673.10 for children. In broad terms, the cost of SLET is approximately 10% of the cost of CLET for adults and 8% for children. CONCLUSION: SLET offers a more accessible and financially attractive alternative to CLET to treat limbal stem cell deficiency.

Assessment of the Role and Timing of Glaucoma Surgery in Boston Keratoprosthesis Type 1 Patients.

PURPOSE: To determine the role and optimal timing of glaucoma surgery in relation to Boston keratoprosthesis type 1 (KPro) implantation. DESIGN: Retrospective, comparative, nonrandomized clinical study. METHODS: Single-center study of a total of 100 eyes (100 patients) implanted with a KPro between 2008 and 2017, and diagnosed with glaucoma before or after KPro. Patients were separated into 2 groups: those with preexisting glaucoma and those who developed de novo glaucoma after KPro. Groups were then divided based on whether patients were medically or surgically managed. Glaucoma surgery included glaucoma drainage device (GDD) implantation, trabeculectomy, and cyclophotocoagulation (CPC). Primary outcomes included best-corrected visual acuity (BCVA), glaucoma progression, and complications. Differences in outcomes were compared using parametric and nonparametric tests, as well as log-rank test to compare time-to-outcome events. RESULTS: Among 72 eyes with preexisting glaucoma, 27 (38%) had glaucoma surgery before KPro (18 GDD), whereas 45 (62%) were medically managed only. Among the latter, 19 (42%) needed glaucoma surgery post-KPro (16 GDD). Among 28 eyes with de novo glaucoma, 12 (43%) had glaucoma surgery post-KPro (9 GDD). For eyes with preexisting glaucoma, glaucoma progression was greater with glaucoma surgery performed post-KPro (100%) compared with pre-KPro (74%, P = .016) and to medical management (54%, P = .002). No increase in complications were observed with glaucoma surgery compared to medications only (P > .05), whereas fewer eyes maintained a BCVA of 20/200 or better over time with medical management (P = .013). Eyes with de novo glaucoma had similar progression, BCVA, and complications between medical and surgical care (P > .05). CONCLUSIONS: Glaucoma surgery should be performed before or at the same time as KPro implantation in eyes with preexisting glaucoma. Complication rates are not increased when glaucoma surgery is performed in KPro eyes with either preexisting or de novo glaucoma. To ensure optimal glaucoma control, glaucoma surgery should be performed as early as possible in KPro eyes with good visual potential.

Comparing ProKera With Amniotic Membrane Transplantation: Indications, Outcomes, and Costs.

PURPOSE: The aim of this study was to compare the outcomes of ProKera versus amniotic membrane transplantation (AMT) in managing ocular surface disease. METHODS: This study is a retrospective case series of patients who received either ProKera or sutured AMT for ocular surface disease. Patient demographics, treatment indications, retention time, percentage healed area, changes in visual acuity, and costs to the health care system were analyzed. RESULTS: Fourteen patients were identified and analyzed for each group. The main indications for using ProKera and AMT were similar, including corneal ulcer or epithelial defect due to chemical burns, neurotropic state, or herpes zoster keratitis. The average time to dissolution or removal was 24.8 days in the ProKera group, compared with 50.1 days in the AMT group. The average percentage of healed corneal area was 59% for ProKera and 73% for AMT. There was no significant difference between the initial and the final visual acuity within groups and when comparing both groups. In our expense analysis, ProKera had a total cost of 699.00 Canadian dollars (CAD), whereas the cost of suture AMT was 1561.52 CAD. ProKera priced at 11.85 CAD for each percentage healed surface area and at 21.39 CAD for AMT. CONCLUSIONS: ProKera allowed for a faster corneal healing than sutured AMT, although its total healed area was less than the latter. Moreover, ProKera is more cost-effective than AMT, thus reducing financial burden to our health care system.

Cost-effectiveness of Descemet stripping automated endothelial keratoplasty versus penetrating keratoplasty in patients with endothelial dysfunction in India.

PURPOSE: The aim of this study was to compare the cost-effectiveness and perform cost-utility analysis of Descemet stripping automated endothelial keratoplasty (DSAEK) vs. penetrating keratoplasty (PK) in Indian population. METHODS: This was an institutional, ambispective, observational study. Patients who underwent PK or DSAEK for endothelial dysfunction were included and followed up for 2 years; those with other ocular comorbidities were excluded. The analysis was performed from the patient's perspective receiving subsidized treatment at a tertiary care hospital. Detailed history, ophthalmic examination, total expenditure by patient, and clinical outcomes were recorded. The main outcome measures were best spectacle-corrected visual acuity (BSCVA), graft survival (Kaplan-Meier survival estimates), incremental cost-effectiveness ratio (ICER), and incremental cost-utility ratio (ICUR). Utility values were based on quality-adjusted life years (QALYs) associated with visual acuity outcomes. Statistical analysis was performed using SPSS software package, version 12.1; a value of P < 0.05 was considered statistically significant. RESULTS: A total of 120 patients (PK: 60, DSAEK: 60) were included. At 2 years, for a similar logMAR BSCVA, [PK (0.32 ± 0.02), DSAEK (0.25 ± 0.02); P = 0.078], the overall cost for PK (13511.1 ± 803.3 INR) was significantly more than DSAEK (11092.9 ± 492.1 INR) (difference = 1952.6 INR; P = 0.01). ICER of DSAEK relative to PK was -39,052 INR for improvement in 1 logMAR unit BSCVA. ICUR of DSAEK relative to PK was -1,95,260 INR for improvement in 1 QALY. CONCLUSION: DSAEK was more cost-effective than PK in patients with endothelial dysfunction at 2 years.

Medication Adherence Among Patients With Corneal Diseases.

PURPOSE: Medication nonadherence is a ubiquitous problem. However, the adherence of patients to medications to manage corneal conditions is unknown. A prospective cohort study investigated the patterns of eye drop adherence among patients with corneal conditions. METHODS: Patients older than or equal to 18 years taking prescription eye medications were recruited from an academic center's corneal clinic. Data collected included age, sex, total doses of eye medications, and category of primary corneal diagnosis. Participants completed adapted versions of the 12-question Adherence to Refills and Medications Scale (ARMS) and the 3-question Voils' Medication Adherence Scale (VMAS). Survey data were dichotomized as "adherent" and "nonadherent," and subscales reported for reasons of nonadherence. Logistic regression analyses were used to test associations with adherence. RESULTS: A total of 199 participants were surveyed from February to March 2019 (95% response rate). Participants were aged 19 to 93 years with a mean age of 59 years (SD 17.8). The percent of participants considered nonadherent was 72% by the ARMS and 33% by the VMAS. Older age was associated with higher adherence by the ARMS (odds ratio = 1.48, 95% confidence interval, 1.14-1.93, P = 0.004) and by the VMAS (odds ratio = 1.24, confidence interval, 1.04-1.48, P = 0.012). Adherence was not significantly associated with race, sex, education, total doses of eye medications, or primary cornea diagnosis. CONCLUSIONS: Medication adherence was lower than expected, particularly on the ARMS scale that asks more detailed questions. Clinicians should engage in conversations about adherence, especially with younger patients, if they are not seeing an expected clinical response.

Ophthalmic Assessment in Patients With Darier Disease.

PURPOSE: To assess the prevalence of ophthalmic findings in patients with Darier disease, an autosomal dominant genetic skin disorder, in an effort to evaluate the need for eye examinations in the management of the disease. DESIGN: Prospective observational case series. METHODS: Thirty-six individuals with Darier disease were evaluated by both ocular assessment questionnaire and a comprehensive ophthalmic examination (visual acuity, refraction, external examination, and slit-lamp examination) with emphasis on the eyelids, conjunctiva, and cornea. In addition, questionnaire-based medical interview and skin examination were conducted. RESULTS: According to the medical questionnaire, 39% of patients reported eye problems, 36% dry eye, and 42% eye fatigue after prolonged reading. Ocular examination revealed Darier disease lesions on the eyelids in 55% of the patients, blepharitis in 44%, conjunctival hyperemia in 28%, and short tear film break-up time in 83%. There was no significant relationship between any of these ophthalmic findings and systemic retinoid therapy, sex, or age. CONCLUSIONS: The high prevalence of blepharitis and dry eye highlights the importance of ophthalmologic evaluation of patients with Darier disease.

Ocular surface assessment in times of sanitary crisis: What lessons and solutions for the present and the future?

PURPOSE: To describe the immediate consequences of SARS-CoV-2 and the COVID-19 pandemic on the ocular surface and eye-care professionals, and to discuss the need for a mandatory switch from currently performed tele-screening to true teleconsultation for remote ocular surface assessment. MAIN FINDINGS: Ophthalmologists have been largely impacted by the COVID-19 sanitary crisis, due to both the ocular manifestations of SARS-CoV-2 and to the high contagiousness of the virus. The proximity of ophthalmologists to their patients have pushed eye-care providers to readapt their practices and develop alternatives to face-to-face consultations. However, teleconsultation has some major limitations and drawbacks, especially for ocular surface assessment that relies on high-quality graphic data for adequate diagnosis. Tele-screening, on the other hand, emphasizes on the importance of history-taking and listening to the patient in order to adequately prioritize appointments based on the presumed degree of emergency. CONCLUSION: Despite all the enthusiasm, tele-screening as currently performed with the available tools is still not capable of completely replacing a standard ophthalmic examination for the assessment of ocular surface diseases. While waiting for new emerging technologies and future implementation of imaging modalities and artificial intelligence, decision making algorithms can help eye-practitioners remotely screen their patients to assess the optimal time for follow-up appointments.

The utility of anterior segment optical coherence tomography angiography for the assessment of limbal stem cell deficiency.

PURPOSE: To determine the utility of anterior segment optical coherence tomography angiography (AS-OCTA) in assessing limbal stem cell deficiency (LSCD). METHODS: Twenty-six eyes of 24 LSCD patients, classified clinically into stage I, II and III, and 12 eyes of 12 healthy subjects were included. AS-OCTA images were analyzed by two masked observers, measuring the maximum corneal vascular extension (CoVE) from the limbus to the furthest vessel over the cornea, and corneal vascular thickness (CoVT) from the most superficial to the deepest corneal vessel. RESULTS: CoVE was 0.27 ± 0.10, 0.79 ± 0.21, 1.68 ± 0.89 and 2.53 ± 0.82 mm in controls, stage I, II and III LSCD, respectively (p < 0.001). The CoVT was 51.0 ± 19.4, 113.7 ± 36.6, 129.7 ± 39.3 and 336.0 ± 85.0 µm, respectively (p < 0.001). There was a significant difference in CoVE and CoVT between all stages compared to controls, and between stage I and III LSCD (p < 0.001). Further, CoVE showed a significant difference between stage I and II, whereas CoVT showed a significant difference between stage II and III LSCD (p < 0.001). BCVA showed strong correlation with CoVT (r = 0.765, p < 0.001) and moderate correlation with CoVE (r = 0.547, p = 0.001). AS-OCTA parameters showed excellent intra- and inter-class correlation coefficients (>0.900). CONCLUSION: LSCD demonstrates significant changes in CoVE and CoVT as early as stage I LSCD in comparison to controls. CoVE and CoVT strongly correlate to both disease severity and BCVA. AS-OCTA may provide novel quantitative and non-invasive parameters to assess LSCD.

SARS-CoV-2: Impact on, Risk Assessment and Countermeasures in German Eye Banks.

INTRODUCTION: Since the beginning of the COVID-19 pandemic there has been some debate regarding the risk of transmission through tissue transplantation and tissue banking processes. AIM OF THE STUDY: To analyze the changes that SARS-CoV-2 has caused regarding the harvesting of corneal donor tissue and eye bank activities in Germany. METHODS: A questionnaire was provided to 26 eye banks in Germany, consisting of questions about adaptations made in the screening of potential donors and the harvesting of corneal tissue following the pandemic spread of SARS-CoV-2. RESULTS: Eighteen eye banks actively reduced recruitment of donors and two banks ceased all activity. Additional diagnostic screening was performed in eight banks, using conjunctival swabs and/or nasopharyngeal swabs. In six eye banks, additional protective measures, such as FFP2 masks and/or facial shields, were implemented. Overall, a mean reduction in the number of obtained donor tissues of 17% was observed. DISCUSSION: Conjunctival and/or nasopharyngeal swabs of donors have been implemented by a minority. Reasons for not performing additional tests may be moderate sensitivity and lack of validation for postmortem use of RT-PCR testing. Also, the hazard of SARS-CoV-2 entering the corneal donor pool with subsequent transmission might be perceived as theoretical. Face shields provide a sufficient barrier against splash and splatter contamination but may be insufficient against aerosols. Additional face masks would provide support against aerosols, but it remains debatable if corneal harvesting can be considered an aerosol-producing procedure. In the future we expect to see changes in current guidelines because of a surge in scientific activities to improve our understanding of the risks involved with cornea donation in the COVID-19 pandemic, and because current practice may reduce the availability of donor corneas due to new exclusion criteria while the demand remains unchanged.

Corneal Blindness in Asia: A Systematic Review and Meta-Analysis to Identify Challenges and Opportunities.

PURPOSE: To describe the causes and prevalence of moderate-to-severe visual impairment (MSVI) and blindness from corneal diseases, as well as corneal transplantation across Asia. METHODS: A meta-analysis of the published literature to identify population-based surveys conducted from 2008 to 2019 in 22 Asian countries regarding the prevalence and causes of MSVI and blindness from corneal disease, and a review of national corneal transplant data and eye bank statistics. RESULTS: A total of 5307 records were screened to identify 57 reports that were used to estimate a prevalence of MSVI and blindness caused by corneal diseases in Asia of 0.38% (95% confidence interval, 0.29%-0.48%). The most frequent corneal diseases were infectious keratitis, trauma, and pseudophakic bullous keratopathy. As expected, these represented the most common indications for corneal transplantation, although the percentages in each country differed based on the level of economic development, with pseudophakic bullous keratopathy being the most common indication in countries with higher gross national income per capita. Despite this, endothelial keratoplasty is not the most commonly performed form of corneal transplantation in any Asian country and represents only a small percentage of keratoplasty procedures performed in most countries. CONCLUSIONS: The prevalence of MSVI and blindness from corneal disease in Asia is approximately 0.4%, with a nearly 20-fold difference in the national prevalence across the region. The indications for keratoplasty, reflective of the causes of corneal dysfunction, also vary, more so according to the gross national income than to geographic location, and only a few Asian countries have rates of corneal transplantation above international means.

Postoperative Complications in Medicare Beneficiaries Following Endothelial Keratoplasty Surgery.

PURPOSE: To determine national-level incidence rates of major postoperative complications following endothelial keratoplasty (EK) procedures and to stratify these rates based on EK indications over an 8-year period using Medicare claims data. DESIGN: Retrospective, cohort study. METHODS: Setting: population-based; study population: Medicare beneficiaries aged ≥65 years who underwent EK procedures; main outcome measurements: 1) occurrence of major postoperative complications (i.e., endophthalmitis, choroidal hemorrhage, infectious keratitis, cystoid macular edema [CME], retinal detachment [RD], or RD surgery) following EK surgery; 2) time-to-event analysis for glaucoma surgery; and 3) occurrence of graft complications. RESULTS: A total of 94,829 EK procedures (n = 71,040 unique patients) were included in the analysis. Of the total, 29% of patients had pre-existing glaucoma. The overall 90-day cumulative incidence of postoperative endophthalmitis and choroidal hemorrhage following EK was 0.03% and 0.05%, respectively. The overall 1-year cumulative rates of RD or RD surgery, infectious keratitis, and CME were 1.0%, 0.8%, and 4.1%, respectively. Approximately 7.6%, 12.2%, and 13.8% of all eyes in this study needed glaucoma surgery at 1-, 5-, and 8-years of follow-up, respectively. The probability of glaucoma surgery among patients with pre-existing glaucoma was 29% vs. 8% among those without pre-existing glaucoma at 8 years. The cumulative probabilities of developing any graft complications were 13%, 23.2%, and 27.1% at 1, 5, and 8 years, respectively, of follow-up. On average, patients undergoing EK procedures for a prior failed graft had the highest rate of complications, whereas those with Fuchs' corneal endothelial dystrophy had the lowest. CONCLUSIONS: The incidence of major postoperative complications including endophthalmitis, retinal detachment, and choroidal hemorrhage following EK procedures is low. A high proportion of eyes undergoing EK eventually require glaucoma surgery and experience graft-related complications. Postoperative outcomes are typically worse for patients undergoing EK for prior failed grafts than for those undergoing EK for Fuchs' corneal endothelial dystrophy.