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This study describes the surgical outcomes of selective endothelialectomy in Peters anomaly (SEPA), a relatively new technique to manage Peters anomaly (PA).This study included 34 eyes of 28 children who had a visually significant posterior corneal defect due to PA and underwent SEPA between 2012 and 2019. A selective endothelialectomy from the posterior corneal defect was performed while preserving Descemet membrane. The primary outcome measure was the resolution of corneal opacification. The secondary outcome measures were functional vision, complications, and risk factors for failure.At a mean postoperative follow-up of 0.96 ± 0.20 years, 29 eyes (85.3%) maintained a successful outcome. Mean preoperative and postoperative best-corrected visual acuities were 2.55 ± 0.13 and 1.78 ± 0.13 ( P0.0001), respectively. Ambulatory functional visual improvement was seen in 97%, and 23% attained vision ranging between 20/190 and 20/50. Corneal opacification failed to clear in 5 eyes (15%). Risk factors associated with surgical failure were female sex ( P = 0.006), disease severity ( P0.0001), glaucoma ( P = 0.001), and additional interventions after SEPA ( P = 0.002). In multivariate analysis, only disease severity (ie, a type 2 PA) was a significant risk factor for the failure of SEPA. There were no sight-threatening complications.SEPA is a safe and effective technique in select cases of posterior corneal defect due to PA. SEPA could be a potential surgical alternative to pediatric keratoplasty or optical iridectomy in children with central corneal opacification smaller than 7 mm due to PA.

Endothelial dysfunction is one of the leading causes of corneal blindness and one of the common indications for keratoplasty. At present, the standard of treatment involves the replacement of the dysfunctional endothelium with healthy tissue taken from a donor. Because there is a paucity of healthy donor tissues, research on the corneal endothelium has focused primarily on expanding these cells in the laboratory for transplantation in an attempt to reduce the gap between the demand and supply of donor tissues for transplantation. To expand these cells, which are nonmitotic in vivo, various mitogens, substrates, culture systems, and alternate strategies have been tested with varying success. The biggest challenge has been the limited proliferative capacity of these cells compounded with endothelial to mesenchymal transition that alters the functioning of these cells and renders them unsuitable for human transplantation. This review aims to give a comprehensive overview of the most common and successful techniques used in the culture of the cells, the current available evidence in support of epithelial to mesenchymal transition (EMT), alternate sources for deriving the corneal endothelial cells, and advances made in transplantation of these cells.

Purpose The purpose of this study was to evaluate the prevalence of SARS-CoV-2 in human postmortem ocular tissues of asymptomatic donors and its implications on our eye banking protocols. Methods The expression of SARS-CoV-2 RNA was assessed by reverse transcription-polymerase chain reaction in corneal rims and conjunctival tissues from 100 donors who were found suitable for transplantation as per the donor screening guidelines of the Global Alliance of Eye Bank Associations. The donor's clinical history and cause of death were assessed for secondary analysis. Results Of 200 ocular tissues (100 corneal and 100 conjunctival) from the same 1 eye of 100 surgical-intended donors, between September 2020 and April 2021, the overall positivity rate for SARS-CoV-2 was ~1% (2/200). Both the ocular samples that tested positive were conjunctival biopsies (2/100, 2%), whereas corneal samples were negative (0/100, 0%) in both donors. The causes of donor death were trauma in 51 donors, suicide in 33, cardiac arrest in 7, electric shock in 5, metabolic cause in 2, malignancy in 1, and snake bite in 1. None of the donors had a medical history suggestive of COVID infection or possible contact. None of the recipients from the donors were reported to have any systemic adverse event after keratoplasty until the follow-up of 6 weeks. Conclusions The overall prevalence of SARS-CoV-2 was 1% (2% for conjunctival and 0% for corneal samples, P value = 0.5) in the donors who were found suitable for cornea recovery and transplantation. The findings of exceptionally low positive rates in our samples validate the criticality of history-based donor screening and do not support the necessity of postmortem PCR testing as a criterion for procurement and subsequent use for corneal transplantation.

The purpose of this study was to compare the corneal endothelial characteristics in Axenfeld anomaly (AXA), Rieger anomaly (RGA), and Axenfeld-Rieger anomaly/syndrome with age-matched healthy controls.This is a retrospective, comparative case-control study of 52 eyes of 30 patients with AXA/RGA and AXA/S and 36 controls.Median age at endothelial imaging was 21.5 years (interquartile range, 13.8-33.3 years). In the study group, the mean endothelial cell density (ECD) was 2112.4 ± 78.5 cells/mm2, the mean cell area (MCA) was 526.9 ± 28.5 μm2, and the coefficient of variation of cell size was 41.2 ± 1.8%. The ECD was significantly (all, P0.0001) lower than controls, while MCA (P0.0001), SD of cell size (P0.0001), and maximum cell area (P = 0.0007) were significantly higher than controls. Four eyes of 3 patients had guttae on slitlamp evaluation and endothelial imaging. There were no differences in the corneal endothelial characteristics among the clinical subtypes.Patients with AXA, RGA, and Axenfeld-Rieger anomaly/syndrome have lower ECD and increased MCA compared with normal eyes. The reduced ECD associated with inherent anterior segment alterations can predispose to the risk of postcataract surgery endothelial decompensation in these eyes. The association of guttae in some eyes needs further investigational studies.

Purpose Xeroderma pigmentosum (XP) is an extreme hypersensitivity to sunlight causing skin freckling and pigmentary changes because of defective DNA repair mechanisms. The purpose of this article is to evaluate the spectrum of ocular and systemic features in XP at a tertiary eye care center in India over 32 years. Methods Data from 418 eyes of 209 patients diagnosed with XP from 1987 to 2018 were reviewed retrospectively for demographics, complaints, ocular features, systemic associations, and their management. Results Median age at diagnosis was 2 years (interquartile range, 0.5-5 years). A total of 124 patients (59.3%) were men. There was parental consanguinity in 74.4% cases. Common ocular complaints were photophobia (47.1%), ocular discomfort (45%), defective vision (36.6%), redness (13.4%), tissue growth (12%), white spot (11.2%), and pain (10.5%). At presentation, 43.5% had corneal scars (45.5% were located inferiorly and 70.9% covered visual axis). Corneal vascularization and limbal stem cell deficiency were noted in 37.4%. A total of 56% of patients had at least 1 tumor, and 6.7% had neurological abnormalities. At least 1 ocular surgery was performed in 37.8% of patients. Ophthalmic surgical interventions included tumor excision (23%), keratoplasty (13.4%), and nontumor ocular surface surgery (3.4%). Conclusions XP is a disorder that has high ocular morbidity in Indian patients. The recognition of common signs and symptoms and relative frequency of various ocular complications with time trends will help in managing and reducing the sequelae of this otherwise untreatable and progressive disease.

Purpose To report the indications, long-term structural and functional outcomes, and prognostic factors for the success of penetrating and lamellar corneal patch grafts. Methods This is a retrospective analysis of 49 patients who underwent the corneal patch graft procedure over 8 years. The baseline, preoperative, and postoperative characteristics along with their outcomes were evaluated. Results Forty-nine eyes (49 patients) with a mean follow-up of 20.3 ± 3.27 months (range 6-48) were included. Thirty-one patients underwent full-thickness grafts for corneal perforation, and 18 underwent lamellar grafts for severe thinning. The most common indication was corneal thinning and/or perforation secondary to microbial keratitis (17 eyes, 34.7%). Anatomic success was achieved in 31 eyes (63.2%), in which no further surgical intervention was required for tectonicity. Functional success was achieved in 22 of 37 eyes (59.5%), where along with anatomic success, significant visual gain was also obtained. Absolute graft failure was noted in 12 eyes (24.5%), which developed recurrence of primary pathology requiring reintervention within the first 6 months. Good prognostic factor for success included sterile corneal perforations. The presence of microbial keratitis was noted to be a guarded prognostic factor for success. Conclusions Corneal patch graft can serve as a good therapeutic modality for corneal ulceration or thinning, not amenable to treatment with tissue adhesive application. Both anatomical success and functional success of 60% was achieved in our series. Those performed for immune-mediated conditions fared the best. Subsequent optical procedures may be performed for further visual rehabilitation at a later stage.

PURPOSE To describe the clinical profile and demographic distribution of corneal dystrophy in patients presenting to a multitier ophthalmology hospital network in India. METHODS This cross-sectional hospital-based study included 2,151,584 new patients presenting between March 2012 and December 2019 (∼8 year period). Patients with a clinical diagnosis of corneal dystrophy in at least 1 eye were included as cases. The data were collected by using an electronic medical record system. RESULTS Overall, 4198 new patients (0.20%) were diagnosed with corneal dystrophy. The prevalence rates were 0.19% in children (age < 16 years) and 0.20% in adults. Most patients were women (51.86%). The mean age of the patients was 43.61 ± 21.39 years. Most patients (18.79%) were between 61 and 70 years of age. The most common anatomical location of the dystrophy was endothelium (51.71%), followed by stroma (43.55%) and Bowman membrane/epithelium (4.73%). The most common corneal dystrophy was Fuch endothelial corneal dystrophy (41.89%). Most eyes had mild or no visual impairment (43.43%). Of the 8193 eyes, 998 eyes (12.18%) underwent a corneal surgery. Among those who underwent surgical intervention, endothelial keratoplasty was the most commonly performed surgical procedure (52%), followed by penetrating keratoplasty (22%). CONCLUSIONS Corneal dystrophy is a rare disease, affecting patients seeking eye care in India. Endothelial dystrophies were the most common, followed by stromal dystrophies. Among the stromal dystrophies, macular dystrophy was the most common. At initial presentation, visual impairment was mild to moderate in most patients, and surgical intervention was needed in 12.18% of the eyes during the study period.

PURPOSE: The tri-folded, endothelium-in approach to Descemet membrane endothelial keratoplasty (DMEK) facilitates tissue insertion into the anterior chamber. We hypothesized that pre-loading tri-folded donor grafts in a cartridge for 48 hours prior to insertion would induce biomechanical changes that decrease their scrolling tendency, compared to tri-folded donor grafts loaded immediately before insertion. METHODS: Ten Descemet membrane donor grafts, peeled and cut to 8.0mm, were prepared by a single eye bank technician. Each graft was tri-folded and pulled into a DMEK cartridge and stored for 48 hours. They were then pulled with microforceps into a petri dish filled with balanced salt solution. A video was taken of the graft becoming a scroll over a 2-minute period. Each graft, serving as its own control, was then tri-folded, pulled into the cartridge, and the process repeated. Images from 1, 5, 10, 60, and 120 seconds were extracted from video recording of the procedures. Scroll width was analyzed by graders blinded to group assignment. A paired t-test was used to determine differences in scroll width at each time point between the 48-hour and instant tri-folding conditions. RESULTS: All grafts scrolled after removal from the cartridge into balanced salt solution. We measured a significant difference at all time points, through 120 seconds (4.02 preloaded vs. 2.91mm instant tri-fold, p=0.035). CONCLUSIONS: Preloading DMEK grafts in a tri-folded configuration for 48 hours reduces the scrolling tendency of Descemet membrane for at least two minutes.

PURPOSE This study was to report the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) in managing corneal endothelial disorders in children less than 14 years of age. METHODS Medical records of 180 DSAEK performed, between 2008 and 2020, on 167 eyes of 111 children who had a visually significant endothelial dysfunction were retrospectively reviewed for the primary etiology of corneal decompensation, time of the onset and duration of cloudiness, preoperative visual acuity, the technique of endothelial keratoplasty, surgical modifications, and reintervention. RESULTS Median age at surgical intervention was 7.9 years (interquartile range, 5.2-11.2 years). At a median postinterventional follow-up of 2.5 years (interquartile range, 0.9-3.4 years), 86.2% (144 of 167 eyes, 95% confidence interval 79.9%-90.1%) maintained a clear graft. Median best-corrected visual acuity (logarithm of the minimum angle of resolution) improved from 1.45 ± 0.70 preoperatively to 0.90 ± 0.06 at the last follow-up visit (P < 0.0001). The cumulative overall long-term graft survival was 92.7%, 86.5%, and 77.7% at 1, 3, and 7 years, respectively. Cox proportional hazards regression analysis showed that the indication for DSAEK (P = 0.007; hazards ratio: 2.17 ± 0.62), age at surgery (P = 0.02; hazards ratio: 0.87 ± 0.05), and any subsequent intervention after DSAEK (P = 0.003; hazards ratio: 0.11 ± 0.08) were significant risk factors for DSAEK failure. The endothelial cell loss was 40.1% at 6 months, 45.4% at 1 year, 55.2% at 5 years, and 61.9% at 7 years. CONCLUSIONS DSAEK is a safe and effective surgical strategy in managing endothelial disorders among the pediatric age group.

PURPOSE To report the outcomes of corneal transplantation using donor corneas retrieved from snakebite victims. METHODS This study was a retrospective analysis of 30 corneal transplants performed from 2014 to 2016 using donor corneas retrieved from snakebite victims. The details of the donor corneal characteristics and the transplant recipients were collected from the eye bank and the medical records department. RESULTS The mean age of the donors was 30.4 ± 17.5 years. The median death-to-preservation time was 3.3 hours [interquartile range: 1.3-5.6 hours]. Ninety percent (27/30) of the corneas were evaluated as optical grade, and 10% (3/30) of the corneas were deemed as therapeutic grade. The mean endothelial cell density on specular microscopy of the donor corneas was 2943 ± 615 cells/mm, and median corneal thickness was 514 μm (interquartile range: 506-520). Seventy-five percent of the corneas transplanted had cleared, with a mean follow-up duration of 1.5 ± 1.0 years (range: 0.4-3.7) years and mean logarithm of the minimum angle of resolution (LogMAR) visual acuity of 0.51 ± 0.27 (range: 0-1.2) at the last follow-up. CONCLUSIONS The donor corneas retrieved from snakebite victims are apparently safe and suitable for transplantation, and screening for such donor corneas should include a thorough examination of ocular adnexa to rule out local envenomation before corneal retrieval in addition to the routine evaluation protocol.

Purpose To compare corneal endothelial damage associated with 2 techniques for preloaded Descemet membrane endothelial keratoplasty (DMEK): a tri-folded graft stored in a plastic cartridge designed for DMEK and a scrolled graft stored in a modified Jones Tube, at the time of preparation and after shipping. Methods DMEK grafts were prepared at the Rocky Mountain Lions Eye Bank. The grafts were either tri-folded and loaded in a plastic cartridge or scrolled and loaded into a modified Jones Tube. In each group, the grafts were then either immediately removed from the cartridges or shipped for 48 hours. The grafts were then stained with Calcein AM and imaged using a fluorescent microscope. Endothelial cell loss (ECL) was determined using trainable segmentation in Fiji by 2 graders. At each time point, rates of ECL loss were compared across the 2 groups. To explore the role of donor characteristics, a multivariable regression model was produced to account for method (tri-folding vs. scroll), donor age, donor gender, death-to-preservation time, death-to-preparation time, and shipping. Results A total of 40 grafts were prepared, processed, imaged, and analyzed. No significant difference in cell loss was seen between groups at either time point alone. In the multivariate model, no significant increase in cell loss was associated with either tri-folding (3.7% less ECL; P = 0.051) or shipping (4.3% less ECL; P = 0.049). Conclusions All techniques used resulted in clinically acceptable levels of ECL. Tri-folded tissue in a plastic cartridge did not result in ECL inferior to a scroll when prepared either immediately or preloaded for 48 hours.

PURPOSE To study the causes of non-utilization of donor corneas and assess whether non-utilized tissues differ from utilized tissues with regard to age and endothelial cell density (ECD). METHODS Aretrospective, cross-sectional analyses of all donor corneas collected from a network of 4 eye banks of a tertiary eye care institute in India during a 1-year period (January to December 2019) was conducted. All donor corneas were assessed for tissue quality by slit lamp evaluation, donor age, and specular microscopy. The causes of non-utilization and effect of donor age and ECD on tissue utilization were studied. RESULTS A total of 10,969 corneas were harvested during the study period; 4618 (42.1%) tissues were discarded. The main causes of non-utilization were poor tissue quality accounting for 86.16% (n = 3979) of all discarded corneas. The mean donor age was 50.7 ± 2.9 years and 63.3 ± 2.3 years for used and discarded corneas, respectively (P < 0.0001). The mean ECD of donor tissues was significantly (P < 0.0001) higher in the utilization group (2787.3 ± 77.4 cells/mm2) than that in the non-utilization group (2394.4 ± 82.5 cells/mm2). Donor age and ECD and their interaction were significant (P < 0.001) predictors of tissue utilization rate. CONCLUSIONS Donor age and ECD and their interaction were significantly associated with the rate of utilization of donor corneal tissues.

Purpose To evaluate the long-term outcomes of Descemet-stripping endothelial keratoplasty (DSEK) in 52 eyes with iridocorneal endothelial (ICE) syndrome. Methods Retrospective study of 52 eyes of 52 patients who were diagnosed with ICE syndrome and underwent DSEK between January 2010 and December 2019 with a follow-up of at least 6 months. Results The mean age was 48.8 +/- 10.8 years. Female patients (n = 33) constituted 63.5%. The median duration of follow-up was 2.4 years (range, 0.5-9.1 yrs). The mean best-corrected visual acuity improved significantly after surgery and remained stable (~20/50) through 5 years. The mean endothelial cell loss was 28%, 37.9%, 43.6%, and 56.9% at 6 months and at 1, 2, and 3 years, respectively. Graft rejection was noted in 5 eyes (9.6%). Postoperatively, increased intraocular pressure (IOP) was seen in 17 eyes (32.7%), and 10 eyes (19.2%) underwent glaucoma surgeries. Fourteen eyes (26.9%) had secondary graft failures. The estimates of graft success were 93.6% +/- 3.6% at 1 year, 85.6% +/- 5.5% at 2 years, 79.3% +/- 6.7% at 3 years, 69.0% +/- 8.9% at 4 years, and 59.1% +/- 11.9% at 5 years. Postoperative increased IOP was found to be the only significant (P = 0.05) risk factor (hazard ratio 8.92) associated with graft failure. The clinical variant of ICE syndrome did not seem to influence the graft survival (P = 0.68). Conclusions In this study, DSEK had a success rate of ~60% at 5 years. Increased IOP post-DSEK is a significant risk factor for graft failure. Graft survival is not affected by the clinical variant of ICE syndrome.

PURPOSE The aim of this study is to determine the presence of oxidative stress markers in the aqueous humor (AH) and corneal tissues of patients with congenital hereditary endothelial dystrophy (CHED). METHODS Interventional prospective study was undertaken to quantify levels of ascorbic acid and glutathione in the AH of patients with CHED. AH was collected from patients undergoing keratoplasty and levels of ascorbic acid and glutathione were determined using biochemical assays and measured spectrophotometrically. AH collected from pediatric patients with cataract were used as control. Corneal sections of patients who underwent penetrating keratoplasty were obtained, and presence of glutathione peroxidase 1, catalase, and superoxide dismutase was determined by immunohistochemistry. Tissue sections obtained from cadaveric corneas unsuitable for clinical transplant were used as control. RESULTS Significantly increased ascorbic acid levels were determined in patients with CHED (605.6 ± 158.9 μM) compared with those in controls (190.5 ± 74.72 μM). However, a trend toward reduced level of glutathione was detected in patients with CHED compared with that in the controls. Increased glutathione peroxidase 1 staining and reduced expression of catalase was detected in corneal tissues of patients with CHED compared with those in control corneal tissues. There was no apparent changes observed in the expression of superoxide dismutase in the corneal sections obtained from patients with CHED. CONCLUSIONS To the best of our knowledge, this is the first study to determine the levels of ascorbic acid and glutathione in AH of patients with CHED. Our data suggest the presence of oxidative stress in CHED that might be responsible for the pathological changes in patients with CHED.

PURPOSE To evaluate Descemet membrane (DM) morphology in eyes with primary congenital glaucoma (PCG) in vivo using high-definition anterior segment optical coherence tomography (ASOCT) and on histopathology. METHODS Corneal scans of patients with PCG (22 eyes of 15 patients) were evaluated for DM morphology and anterior chamber angle using ASOCT. The DM thickness in PCG eyes was compared with fellow eyes (8 eyes) of unilateral patients with PCG and healthy controls (12 eyes) on ASOCT. The DM morphology was also compared on the histopathology of corneal tissues (9) obtained from PCG eyes after keratoplasty and enucleated eyes of retinoblastoma (6 controls) on light microscopy with immunostaining for collagen IV. RESULTS On ASOCT, all affected eyes showed the presence of either a thickened DM complex or a hyper-reflective double layer representing the thickened DM and pre-Descemet layer (PDL), unlike a single membrane in the controls and fellow eyes. On ASOCT, among patients with PCG, the DM showed significant thickening (32.0 ± 11.2 μm) versus fellow eyes (14.4 ± 3.3 μm) and controls (11.5 ± 1 μm) (P < 0.001; analysis of variance). The thickened DM complex continued peripherally into the trabecular meshwork as an abnormal membrane in 16/22 affected eyes. On histopathology, thickening of DM was also more among PCG eyes (median: 67.9 μm range: 27.2-214.9) versus controls (median: 27.7 μm, range: 22.1-36.1; P = 0.005) as also of PDL (median: 14 μm, range: 5.9-30.5) of PCG versus (median 3.5, range: 1.3-6.7 μm) in controls; P = 0.014. CONCLUSIONS Thickening of DM and PDL occurs in eyes with PCG and is seen to have a peripheral extension upto the angle recess.

Purpose Preloaded, trifolded grafts in Descemet membrane endothelial keratoplasty require transfer of the trifolding process from the corneal transplant surgeon to the eye bank technician. We sought to assess whether trifolding may be safely conducted by an eye bank technician with cell loss comparable to standard peeling and lifting. Methods A total of 10 grafts were stained, peeled, and transferred directly onto a bed of Calcein-AM and Amvisc Plus by an eye bank technician. Five grafts were removed and stained as a scroll, and 5 grafts were trifolded with the endothelium in before transfer. Photographs were acquired with an inverted fluorescence microscope, and image segmentation was performed. A t test was conducted to compare differences in endothelial cell loss across groups. Results Mean cell loss in the scroll group was 18.5% [95% confidence interval (CI): 15.2%-21.9%] compared with 7.6% of the trifolded group (95% CI: 1.7%-13.5%). A 2-tailed t test indicated decreased cell loss in the trifolded group (P = 0.013). Conclusions Despite additional manipulation of the graft, trifolding of Descemet membrane and endothelium may be performed by an eye bank technician without significantly increased cell loss relative to graft preparation as a scroll.

Purpose To evaluate parents of probands affected with autosomal recessive congenital hereditary endothelial dystrophy (CHED) for clinical signs of Fuchs endothelial corneal dystrophy (FECD) and to determine the genotypes of the SLC4A11 gene in the probands and their parents. Methods This study involved 9 patients affected with CHED from 8 families. The parents of such probands were examined to investigate for possible signs of FECD although they did not present with any visual complaints. Blood samples were collected after obtaining consent, from all 9 cases and the parents of each proband, for genetic analysis. Genomic DNA isolated from blood leukocytes was used for genetic analysis. Screening of the coding regions of the SLC4A11 gene for mutations was carried out by standard procedures using polymerase chain reaction (PCR) amplification and sequencing. Sequences were checked against the human SLC4A11 reference sequence to detect alterations and in normal control samples available in the laboratory. Results The probands had characteristic signs of CHED, whereas one of the parents of each of the probands showed early signs of FECD, characterized by the presence of guttae in the central cornea corroborative with the diagnosis of FECD, and were otherwise asymptomatic at that time. The CHED-affected probands were homozygous for various SLC4A11 mutations, and their parents were heterozygous for the same. The mutations included missense mutations in 6 probands and nonsense mutations in 2 cases. Conclusions Heterozygosity for SLC4A11 mutations in the parents of children with autosomal recessive CHED appears to be a risk factor for the development of FECD in these cases.

PURPOSE To evaluate the relationship between endothelial cell density (ECD) and mean corneal diameter (MCD) in eyes with uveal coloboma associated with microcornea. METHODS Corneal endothelial cell imaging was performed using specular microscopy on 22 eyes of 18 subjects diagnosed with uveal coloboma associated with microcornea. The MCD was noted as the average of horizontal and vertical corneal diameters, which were measured using the ruler tool of the slit-lamp biomicroscope and Castroviejo calipers. RESULTS Mean age of the study subjects was 29.7 ± 10.4 years (range, 14-46 years). The MCD was 7.3 ± 1.1 mm (range, 4.9-9 mm). Mean ECD (3436 ± 316.2 cells/mm) of the study subjects was significantly (P < 0.0001) higher than the mean ECD (2761.8 ± 140.9 cells/mm) of age-matched (range, 10-40 years) normal eyes with no ocular pathology. The pleomorphism and polymegathism were comparable between the 2 groups. Regression analysis showed that MCD had a significant negative (R = -0.55; P = 0.02) relationship with ECD. CONCLUSIONS Eyes with congenital uveal coloboma associated with microcornea have increased ECD. Increased ECD may be partly due to a reduced posterior corneal surface area in microcornea.