Donor Corneal Research Articles

Discrepancies in Endothelial Cell Density Values of Human Donor Corneas Resulting From Comparison Between Specular Microscopes and Endothelial Analysis Methods.

The methods for specular microscopy evaluation across eye banks differ, which may result in variability in endothelial cell density (ECD) values that influence the surgeon's decision about donor tissue. A comparison of instruments and analysis methods is conducted in this study. Specular images were captured from 97 donor corneas using both HAI and Konan specular microscopes. A single best quality image of each cornea from each instrument was graded using the respective inherent software and analysis method (HAI: variable frame method; Konan: center method). All raw specular images were standardized for dimensions and regraded in the CellChek system in a blinded fashion. The grading variances and paired t test were performed between instruments in both inherent and standardized analyses. Correlation and Bland-Altman analyses between instruments were also performed. Using the software inherent within HAI and Konan, the mean ECD readings for the 97 corneas were 2764 ± 583 and 2605 ± 517 cell/mm (P = 0.045), respectively, with a variance of 8.05% (range 0.26%-27.2%). HAI resulted in a higher ECD value in 79 corneas (81.4%). In CellChek software analysis, the mean ECD readings did not differ (2609 ± 514 and 2496 ± 507 cells/mm, respectively, P = 0.127), with a variance of 5.6% (range 0.24%-19.8%). There is a slight statistically significant mean difference between the ECD values obtained from the 2 specular microscopes, which is negated by standardization to a single analysis method. Eye banks and surgeons should use caution in making decisions based only on very small differences in ECD between otherwise equivalent corneal donor tissues.

A standardized methodology for longitudinal assessment of corneal endothelial morphometry in eye banked corneas.

Eye banked research-grade human donor corneas serve as principal ex vivo source for studying the mechanisms that underlie corneal endothelial cell damage/death and survival. Wide-field specular microscopy can be used for corneal endothelial visualization and allows for indirect assessment of endothelial cell function by analyzing endothelial cell density and morphometric parameters. However, a standardized approach is needed to observe corneal endothelial changes over time. This protocol describes reliable ex vivo methods for consecutive analyses of human donor corneal endothelial cell density and morphometric parameters change using a wide-field dual imaging specular microscope. This protocol involves tissue warming, acquisition and analysis of specular endothelial images, assessment of corneal layers with the new Enhance mode, optical pachymetry measurement, and qualitative image quality grading scales. This quantitative and qualitative evaluation of donor corneas allows for a systematic analysis of endothelial dynamic responses to ex vivo induced stress and can be used as a valuable tool to better elucidate specular findings and mechanisms mediating corneal endothelial cell loss in corneal disease and after transplantation.

Awareness and attitudes toward corneal donation among applicants and staff of a driver, vehicle and licensing authority (DVLA) in Ghana

BackgroundCorneal transplantations are surgeries performed for irreparable corneal diseases and damage. However, there is a gap between the number of potential recipients and the number of donor corneas available. The main aim of the study was to determine the awareness and attitudes toward corneal donation among applicants and staff of DVLA, Kumasi-Ghana.MethodsA descriptive cross-sectional study was conducted. One hundred participants were selected using convenient sampling method. A structured questionnaire was used to elicit responses from participants concerning awareness and attitudes toward corneal transplant.ResultsThe mean ± SD age of the participants was 32.05 ± 11.48 years and age range, 18-67 years. Males were 66% whilst females constituted 34%. 32.7% of the participants were aware of corneal donation. Majority of the participants were Christians (83.1%) and Singles (63%). Television was the source of information with the highest preponderance (49.4%). 67.3% were willing to donate their corneas after death. 63.9% were willing to indicate their donor statuses on drivers’ license form which had a significant association with willingness to donate cornea after death (p < 0.05, x2 = 12.187).ConclusionThere is a poor level of awareness (32.7%) of transplant and donation amongst the study population but a good level of willingness to donate organs (67%). Consent via driving license would seem to be a good potential mode of obtaining consent to supplement the harvesting of adequate tissues for transplant if adequate awareness is created.

330.9: Organ donations made possible through a toll-free information service – the new facet of an Organ Donation Helpline in India.

Background: In 2012 MOHAN Foundation initiated a toll-free helpline facility to answer questions related to organ donation. The service, available 24/7 in 8 Indian languages, manned by trained counselors, receives close to 1200 calls every month. The most frequently asked questions are: - What is organ donation and how can one donate? - How can an organ be obtained? - How can I buy/sell a kidney? Alongside such calls, over the years, the helpline has also started receiving calls from family members expressing their wish to donate the organs/tissues of their deceased relatives. This case study analyses this unexpected outcome and how it could benefit the organ donation scenario. Methods: The period of the study was from January 2017 to December 2018 when a new reporting system was added to the helpline log. An algorithm that allows the counselor to communicate the information received from a caller to a regional coordinator and help the family member in fulfilling their objective was designed. A list of eye banks, skins banks and bone banks was made available to the counselors for reference. Likewise, contact information of medical colleges accepting voluntary body donations were compiled. The counselors were instructed to make note of such calls and write a brief report and the outcome. Follow-up calls were made to gather additional information when required. Results: In 2017, the helpline was instrumental in making 12 cases of donations possible. Two of these were multi-organ DBD and 10 were successful tissue donations. 2018 witnessed 15 donations, of which 13 were tissue donations and the other two, multi-organ DBD. In the organ donation cases, the calls were from the relatives of patients who were admitted in a hospital. The calls were made for seeking further clarifications and possible apprehension about brain stem death, procedures within hospitals, possible delays in handing over the body and the process of organ allocation. Once they were convinced that the hospitals were following approved protocols, consent for donation was given. In case of tissue donations, corneal donation was the most common. In most instances the families had already decided and wished to donate and wanted to know how to proceed further. This outcome of helpline has contributed significantly to the pool of solid organs and tissues. This required training the helpline counselors more rigorously and also led to design of an ‘Organ Donation Helpline App’. It is indeed a positive outcome of the information service that was initiated more than 5 years ago. There is also a positive feel-good factor among the counselors when they report such successful donations and encourages them to go the extra mile to make a difference. Conclusions: The helpline provides information about organ donation and clears misconceptions, and also coordinates actual organ donations. It is indeed a useful tool that has scope for great enhancements to improve the donation rates in a country. State Bank of India Foundation.

The Rapid Transformation of Transplantation for Corneal Endothelial Diseases: An Evolution From Penetrating to Lamellar to Cellular Transplants.

The cornea is the major focusing structure of the human eye and the corneal endothelium maintains the relatively dehydrated state of the cornea required for clarity. The endothelial cells respond to disease or injury by migration and cellular enlargement. Our current understanding is that there is a very limited degree of proliferative or regenerative capacity in the human corneal endothelium. Thus, corneal endothelial diseases may result in corneal edema, significantly impact vision and quality of life. Contemporary surgical transplantation options for treating moderate to advanced endothelial dysfunction include penetrating keratoplasty (PK), Descemet stripping endothelial keratoplasty (DSEK), and Descemet membrane endothelial keratoplasty. Advances in surgical techniques aim to bring faster visual recovery and improve visual outcomes; however, there is still a significant donor cornea shortage worldwide and alternative methods for treatment for corneal endothelial disease are rapidly evolving. Indeed, we are at a pivotal point in corneal transplantation for endothelial disease and novel surgical strategies include using 1 donor for multiple recipients, a minimally attached endothelial graft, and Descemet membrane stripping only. Crucially, forthcoming approaches include the use of Rho-Kinase (ROCK) inhibitors, endothelial cell therapy, tissue engineered grafts, and consideration of stem cell techniques. Ultimately, the choice of technique will be dependent on recipient factors such as age, type of endothelial disease, extent of the disease, and associated ocular disorders. The safety and efficacy of these rapidly developing treatments warrant further investigations. In time, some or all of these alternatives for corneal transplantation will alleviate the reliance on limited corneal donor tissue.

Regulatory T cells promote corneal endothelial cell survival following transplantation via interleukin-10.

The functional competence of corneal endothelial cells (CEnCs) is critical for survival of corneal allografts, but these cells are often targets of the immune response mediated by graft-attacking effector T cells. Although regulatory T cells (Tregs) have been studied for their role in regulating the host's alloimmune response towards the graft, the cytoprotective function of these cells on CEnCs has not been investigated. The aim of this study was to determine whether Tregs suppress effector T cell-mediated and inflammatory cytokine-induced CEnC death, and to elucidate the mechanism by which this cytoprotection occurs. Using 2 well-established models of corneal transplantation (low-risk and high-risk models), we show that Tregs derived from low-risk graft recipients have a superior capacity in protecting CEnCs against effector T cell-mediated and interferon-γ and tumor necrosis factor-α-induced cell death compared to Tregs derived from high-risk hosts. We further demonstrate that the cytoprotective function of Tregs derived from low-risk hosts occurs independently of direct cell-cell contact and is mediated by the immunoregulatory cytokine IL-10. Our study is the first to report that Tregs provide cytoprotection for CEnCs through secretion of IL-10, indicating potentially novel therapeutic targets for enhancing CEnC survival following corneal transplantation.

Six-Month Results of Descemet Membrane Endothelial Keratoplasty in 100 Eyes: First Clinical Results from Turkey

Objectives:To evaluate the 6-month outcomes of Descemet membrane endothelial keratoplasty (DMEK) in patients with pseudophakic bullous keratopathy (PBK) and Fuchs’ endothelial dystrophy (FED) in a single center in Turkey.Materials and Methods:The medical records of patients who underwent DMEK were reviewed retrospectively. Best corrected visual acuity (BCVA), donor corneal endothelial cell density (ECD), donor age, duration in solution after obtaining the donor tissue, and duration after exitus of the donor were evaluated preoperatively and BCVA, ECD, and ECD loss (%) at postoperative 6 months were evaluated postoperatively. Graft detachment, graft failure, and pupillary block were recorded as surgical complications. Patients with cataract and FED underwent combined or staged procedures. Two different graft preparation techniques were utilized: 8 and 9.5 mm.Results:One hundred eyes of 74 patients were included in the study. Fifty-two of the eyes had FED and the remaining 48 had PBK. Mean ECD loss in 6 months was 29.2±4.4% in the FED group and 29.7±5% in the PBK group (p=0.415). Mean BCVA at 6 months was 0.06±0.05 in the patients with FED and 0.07±0.05 in the patients with PBK (p=0.378). Mean ECD loss in 6 months was 28.3±5.3% in the 8 mm group vs. 29.7±4.5% in the 9.5 mm group (p=0.255), and 28.5±5.6% in the combined group vs. 29.8±2.9% in the staged group (p=0.279).Conclusion:Different graft preparation techniques can be utilized with similar efficiency for DMEK surgery. A staged or combined approach can be used efficiently in the management of patients with FED and cataract. Our results are promising both for PBK and FED patients.

Peripheral Reconstructive Lamellar Keratoplasty for Late Ectasia After Penetrating Keratoplasty in Keratoconus Eyes.

To describe outcomes of customized peripheral anterior lamellar keratoplasty (PALK) for late ectasia of the donor-recipient junction after penetrating keratoplasty (PK) for keratoconus. This was a single-center, retrospective review of 33 eyes (28 patients) that developed ectasia restricted to the graft-host junction; 17 eyes underwent PALK using lamellar resections of 8- to 11-mm width starting at the external margin of the previous PK and suturing a same-size donor graft (annular or segmental). Five eyes were excluded from analysis because of postoperative complications unrelated to the technique. The average time between PK and diagnosis of secondary ectasia was 28 years (range 9-49 years). Slit-lamp examination showed localized thinning and elongation of the scar at the graft-host junction with well-defined biomicroscopic limits. Preoperatively, the mean keratometric measures were K1: 44.8 ± 4.8 D and K2: 54.1 ± 4.8 D and postoperatively K1: 47.5 ± 3.5 D and K2: 50.8 ± 2.6 D. The mean improvement in corrected visual acuity was 10 lines, and mean cylinder improved from 9.3 ± 2.1 D to 3.3 ± 1.4 D. All cases showed anatomical and refractive improvement. With long-term follow-up, late post-PK ectasia becomes an increasing problem. PALK can be a successful surgical option to reinforce the ectatic area while preserving a functional clear PK. By adding donor corneal tissue, PALK restores the ectatic area, improves visual acuity, keratometric values, and astigmatism, and preserves the functional graft while avoiding the higher risks of a larger diameter PK.

Quantitative assessment of human donor corneal endothelium with Gabor domain optical coherence microscopy.

.We report on a pathway for Gabor domain optical coherence microscopy (GD-OCM)-based metrology to assess the donor’s corneal endothelial layers ex vivo. Six corneas from the Lions Eye Bank at Albany and Rochester were imaged with GD-OCM. The raw 3-D images of the curved corneas were flattened using custom software to enhance the 2-D visualization of endothelial cells (ECs); then the ECs within a circle of -diameter were analyzed using a custom corner method and a cell counting plugin in ImageJ. The EC number, EC area, endothelial cell density (ECD), and polymegethism (CV) were quantified in five different locations for each cornea. The robustness of the method (defined as the repeatability of measurement together with interoperator variability) was evaluated by independently repeating the entire ECD measurement procedure six times by three different examiners. The results from the six corneas show that the current modality reproduces the ECDs with a standard deviation of 2.3% of the mean ECD in every location, whereas the mean ECD across five locations varies by 5.1%. The resolution and imaging area provided through the use of GD-OCM may help to ultimately better assess the quality of donor corneas in transplantation.

Biologic stromal ring to manage stromal melting after intrastromal corneal ring segment implantation

We report a new technique to replace a manufactured poly(methyl methacrylate) (PMMA) ring with a biologic stromal ring fashioned from human corneal donor tissue in eyes with stromal melting above the PMMA ring. The biologic stromal ring is prepared using manual or femtosecond laser trephination of a donor cornea to obtain a 360-degree ring that is denuded and adjusted to match the PMMA ring being replaced. The biologic ring is attached to the PMMA ring. The PMMA ring is pushed and retrieved from the other side, which installs the biologic ring in place. Six biologic stromal rings were implanted successfully in 5 eyes of 5 patients with previous stromal melting; no complications were reported up to 6 months postoperatively. The biologic stromal ring stopped and healed the melting, prevented further ring complications, and preserved the therapeutic refractive effect of the previously implanted PMMA ring.

Knowledge and attitude regarding eye donation among the people of rural area in Kinaye, Belagavi: a cross sectional study

Background: Corneal diseases are the second major cause of blindness. Corneal transplantation is the most effective treatment with high rate of success but there is a shortage of corneal donors. The study analyzed various factors affecting the willingness to donate cornea.Methods: This community based cross sectional study was conducted among the adults residing in 9 sub-centres under PHC Kinaye, Belagavi in Karnataka, India. The participants (n=400) answered questionnaires which included details such as the demographic profile and, awareness and willingness to donate eyes. Univariate logistic regression analysis was performed for the data.Results: Out of 400 participants, 80.5% were aware of eye donation among which 52% were willing to donate. Univariate analysis showed that adults who were less than 40 years were more aware when compared to those who were more than 40 years (p=0.0001) and more educated adults were willing to donate than illiterate. Adults from joint family were more aware when compared to those from nuclear family (p=0.005). Religious beliefs influenced the willingness of adults for donation as 83.6% denied willingness to donate.Conclusions: The results of our study strongly suggest that there are a lot of misconceptions regarding eye donation in most parts of our country. It is evident from our study that education and involvement of those in health sector, will help to spread knowledge about eye donation and to eliminate misconceptions and ignorance about corneal donation.

Biocompatibility evaluation of bioprinted decellularized collagen sheet implanted in vivo cornea using swept-source optical coherence tomography.

Corneal transplantation by full‐thickness penetrating keratoplasty with human donor tissue is a widely accepted treatment for damaged or diseased corneas. Although corneal transplantation has a high success rate, a shortage of high‐quality donor tissue is a considerable limitation. Therefore, bioengineered corneas could be an effective solution for this limitation, and a decellularized extracellular matrix comprises a promising scaffold for their fabrication. In this study, three‐dimensional bioprinted decellularized collagen sheets were implanted into the stromal layer of the cornea of five rabbits. We performed in vivo noninvasive monitoring of the rabbit corneas using swept‐source optical coherence tomography (OCT) after implanting the collagen sheets. Anterior segment OCT images and averaged amplitude‐scans were acquired biweekly to monitor corneal thickness after implantation for 1 month. The averaged cornea thickness in the control images was 430.3 ± 5.9 μm, while the averaged thickness after corneal implantation was 598.5 ± 11.8 μm and 564.5 ± 12.5 μm at 2 and 4 weeks, respectively. The corneal thickness reduction of 34 μm confirmed the biocompatibility through the image analysis of the depth‐intensity profile base. Moreover, hematoxylin and eosin staining supported the biocompatibility evaluation of the bioprinted decellularized collagen sheet implantation. Hence, the developed bioprinted decellularized collagen sheets could become an alternative solution to human corneal donor tissue, and the proposed image analysis procedure could be beneficial to confirm the success of the surgery.

A physical biomarker of the quality of cultured corneal endothelial cells and of the long-term prognosis of corneal restoration in patients.

Dysfunction of the corneal endothelium reduces the transparency of the cornea and can cause blindness. Because corneal endothelial cells have an extremely limited proliferative ability in vivo, treatment for corneal endothelial dysfunction involves the transplantation of donor corneal tissue. Corneal endothelium can also be restored via intraocular injection of endothelial cells in suspension after their expansion in vitro. Yet, because quality assessment during the expansion of the cells is a destructive process, a substantial number of the cultured cells are lost. Here, we show that the 'spring constant' of the effective interaction potential between endothelial cells in a confluent monolayer serves as a biomarker of the quality of corneal endothelial cells in vitro and of the long-term prognosis of corneal restoration in patients treated with culture-expanded endothelial cells or with transplanted corneas. The biomarker can be measured from phase contrast imaging in vitro and from specular microscopy in vivo, and may enable a shift from passive monitoring to pre-emptive intervention in patients with severe corneal disorders.

Phototherapeutic keratectomy

Phototherapeutic keratectomy is an excimer laser–based surgical procedure widely performed by corneal surgeons for treating anterior corneal stromal pathologies. Phototherapeutic keratectomy helps by ablating the corneal stroma, thereby improving corneal clarity and smoothening the surface. Transient discomfort and induced hyperopia from corneal flattening are the immediate postoperative concerns. The long-term course is often marked by the recurrence of original corneal pathology and corneal haze formation. Phototherapeutic keratectomy, however, allows for repeat stromal ablation for managing recurrences, as the corneal thickness permits, without affecting the outcome of future keratoplasty. Adjunctive methods such as topical mitomycin-C may be additionally used to reduce recurrence rates. Also, various masking agents such as carboxymethyl cellulose, sodium hyaluronate, and dextran are used in eyes with irregular corneal surface to allow for uniform stromal ablation. Overall, phototherapeutic keratectomy has provided corneal surgeons an additional surgical tool, particularly those residing in developing nations where the availability of donor corneal tissue is an important limiting factor.

Allogenic corneal tissue transplantation in substitution for extruded intracorneal rings: A case series

We describe a case series of four eyes of four keratoconus patients with extruded intracorneal ring segments (ICRS) in whom donor corneal tissue was used to substitute for the extruded ICRS in an attempt to preserve its effect. In all patients, the extruded intracorneal ring was removed through the exposed area. Donor corneal tissue (tailored to the size and shape of the ICRS) was inserted into the empty ICRS tunnel and fixed in place using 10-0 nylon sutures. At three months follow-up, all patients had a healed graft and displayed a stable Kmax, best corrected visual acuity (BCVA) and corneal topography comparable to the preoperative values. Replacing extruded intracorneal rings with donor tissue grafts in keratoconus patients appears to be a promising technique in preserving the effect of the corneal ring and possibly in treating primary keratoconus with donor tissue segments. Refinement of the technique, longer follow-up, and a larger study population is warranted.

Prelamellar Dissection Donor Corneal Thickness Is Associated With Descemet Stripping Automated Endothelial Keratoplasty Operative Complications in the Cornea Preservation Time Study.

To identify donor and recipient factors, including eye bank tissue observations, predictive of operative complications in the Cornea Preservation Time Study. One thousand three hundred thirty study eyes undergoing Descemet stripping automated endothelial keratoplasty for Fuchs dystrophy or pseudophakic/aphakic corneal edema were randomized to receive a donor cornea with preservation time (PT) of 0 to 7 days (N = 675) or 8 to 14 days (N = 655). Donor factors included demographics, prelamellar corneal and postlamellar lenticule dissection thickness, central endothelial cell density, and tissue processing time. Recipient factors included demographics, intraocular pressure, and glaucoma medications or surgery (trabeculectomy, laser trabeculoplasty). Eye bank observations included donor tissue folds, pleomorphism/polymegethism, and endothelial cell abnormalities. Possible tissue-related operative complications were recorded including difficult donor lenticule unfolding and positioning. Multivariable logistic regression with backward selection was used to identify statistically significant (P < 0.01) associations between factors and operative complications. The only factor predictive of operative complications [58 (4.4%) of 1330 surgeries] was prelamellar dissection donor corneal thickness (P = 0.002). For every 50 μm of donor corneal thickness prior to lamellar dissection, operative complication odds increased by 40% (odds ratio [99% confidence interval (CI)]: 1.40 [1.06-1.83]) adjusting for PT and whether the epithelium was on or off. The estimated mean prelamellar dissection donor corneal thickness for PT 0 to 7 days was 537 μm (99% CI: 516 μm-558 μm) compared with 567 μm (99% CI: 546 μm-588 μm) for PT 8 to 14 days (P < 0.001). Thicker donor tissue (prelamellar dissection) is associated with operative complications and should be considered in tissue selection for Descemet stripping automated endothelial keratoplasty lenticule preparation.

Increasing Povidone-Iodine Exposure in Endothelial Keratoplasty Tissue Processing and Fungal Infection Impact.

To evaluate the effect on donor rim cultures and postoperative infections of doubling the povidone-iodine exposure time during corneal tissue recovery before its use in keratoplasty. Consecutive donor cornea recoveries were evaluated for positive donor corneal rim cultures and postoperative infections before and after a protocol change of doubling the exposure time of povidone-iodine during donor preparation. In 631 consecutive cornea donor recoveries, 18 (2.9%) had positive fungal rim cultures and 41 (6.5%) had positive bacterial rim cultures. Three (0.48%) developed postoperative fungal infections, and no bacterial infections occurred. After doubling the povidone-iodine exposure time during the recovery process, 725 consecutive corneas were reviewed. Four (0.6%) had positive fungal rim cultures, and 29 (4.0%) had positive bacterial rim cultures. No postoperative fungal or bacterial infections occurred. No noticeable increase in epithelial toxicity developed between the 2 groups. Increasing the povidone-iodine exposure time during the donor cornea recovery process decreased the rate of positive donor corneal rim fungal cultures (P = 0.001), positive donor corneal rim bacterial cultures (P = 0.04), and postoperative fungal infections (P = 0.06).

Microbiological Screening of Hypothermic Preserved Donor Corneas in Keratoplasty

ABSTRACTPurpose: To determine the prevalence, risk factors and microbial profiles of donor corneal contamination and its association with postoperative infection.Materials and Methods: 1348 hypothermic preserved donor corneas were screened during keratoplasty to assess the impacts of donor age, gender, cause of death and corneal preservation time on the contamination risk. The microbial spectrum and antibiotic sensitivity of causative microorganisms and the prognostic role of corneoscleral rim cultures were analyzed.Results: 111 donor corneas (8.2%) had positive microbial cultures, with 84 contaminated by bacteria, 25 by fungi and 2 by both. Acinetobacter baumannii complex (19.8%) and Candida spp. (9.0%) were the most commonly isolated bacteria and fungi, respectively. Two patients (1.8%) who received contaminated corneal buttons developed postoperative infections. Death due to cardiac disease led to more corneal contaminations than death due to brain disease (odds ratio (OR) = 2.59, P = .009). Longer preservation time was associated with a trend toward increasing contamination rate (from 8.3% to 15.0%). Moreover, fungal-contaminated corneas were preserved longer than bacterial-contaminated corneas (6.6 ± 4.5 versus 10.2 ± 5.4 days, P = .001). Corneas from donors who died from cardiac diseases and trauma showed the highest prevalence of bacterial (10.9%) and fungal (2.6%) contamination, respectively. Antibiotic sensitivity testing revealed that the third-generation fluoroquinolone levofloxacin had high rates of susceptibility to both gram-positive (G+) (60.0%) and gram-negative (G-) (44.6%) bacteria.Conclusions: The causes of donor corneal contamination are multifactorial. The antibiotic resistance rate of contaminating microbes seems to be increasing. Whether antibiotic usage in storage medium and postoperative prophylaxis should be updated accordingly warrants further investigation.

Descemet\u2019s membrane endothelial keratoplasty for pseudoexfoliation syndrome: a case series

BackgroundTo evaluate the clinical outcomes and features of Descemet’s membrane endothelial keratoplasty (DMEK) for eyes with pseudoexfoliation syndrome (PEX).MethodsIn this retrospective study, 37 DMEK cases were reviewed from available medical records. Patients who exhibited endothelial dysfunction derived from PEX or Fuchs endothelial corneal dystrophy (FECD) and successfully underwent cataract surgery about four weeks before DMEK were enrolled. The best spectacle-corrected visual acuity (BSCVA), central corneal thickness (CCT), endothelial cell density (ECD), and incidence of intra-operative/post-operative complications of DMEK were analyzed.ResultsThis study included 14 eyes of 14 patients (PEX: n = 6, FECD: n = 8). There was no primary graft failure. In the PEX group, BSCVA improved from 0.67 ± 0.28 at the preoperative point to 0.43 ± 0.14 at 1 month, 0.27 ± 0.10 at 3 months, and 0.19 ± 0.08 at 6 months after DMEK. The donor corneal ECD was 2704 ± 225 cells/mm2 at the preoperative point and decreased to 1691 ± 498 cells/mm2 at 1 month, 1425 ± 366 cells/mm2 at 3 months, and 1281 ± 340 cells/mm2 (52.7 ± 11.7% less than ECD of the donor graft) at 6 months after DMEK. None of the patients required rebubbling. When compared with the FECD group, no statistical difference was observed in CCT (p = 0.821); BSCVA (p = 0.001) and the reduction rate of ECD (p = 0.010) were relatively worse.ConclusionsDMEK is effective for the treatment of endothelial dysfunction due to PEX.

Comparing Knowledge of Corneal and Organ Transplantation and Attitudes towards Corneal and Organ Donation among University Health Students in Kumasi - Ghana

Comparing Knowledge of Corneal and Organ Transplantation and Attitudes towards Corneal and Organ Donation among University Health Students in Kumasi - Ghana