Utilization rate of corneal tissue obtained from donors over 75 years of age in Western India for keratoplasty

Purpose: To examine the utilization patterns of cornea procured from diseased individuals ?75 years of age at an eye bank in western India. Methods: In this retrospective study, data from 1,217 eyes of 653 donors with age ?75 years were reviewed from October 2008 to December 2019. Donor age, lens status, endothelial cell count (ECD), utilization of the tissue for transplantation or non?clinical purposes (e.g., research, training/discarded), and causes of non?utilization were noted. Results: The mean age of the donors was 80.9 ± 4.6 years and the tissue utilization rate was 36.5% (445 out of 1,217 eyes). The eyes used for keratoplasty procedures had a lower donor age (79.6 ± 5.7 vs. 81.5 ± 5.1; P < 0.001), a higher endothelial cell count (2493 ± 531 vs. 2034 ± 581; P < 0.001), and were more often phakic (61% vs. 36.6%) compared to the unused group. A multivariable logistic regression analysis showed that the likelihood of tissue utilization for keratoplasty was 13% higher with every 100?cell increment in donor ECD (odds ratio [OR] = 1.13, 95% CI = 1.10–1.16, P < 0.001) and 33% lower with having a pseudophakic status in the donor eye (OR = 0.67, 95% CI = 0.52–0.87, P = 0.03). Age was not a significant determinant of tissue utilization when used in the same multivariable model. Conclusion: More than one?third of the eyes (36.5%) can be utilized even when the donors are above 75 years of age. Eyes that were more likely to be utilized for keratoplasty were phakic and had a significantly higher ECD; age was not a determinant in tissue utilization

Postoperative detection of unusual pathology in donor corneal tissue

We present a series of three patients with previously undetected corneal pathology in grafted corneal tissue following keratoplasty for keratoconus. Postoperatively, a faint layer of anterior stromal haze involving the graft was observed in each patient upon slit lamp examination. Anterior segment optical coherence tomography (AS-OCT) confirmed the presence of anterior stromal scarring across the transplanted cornea. However, the ocular and systemic medical histories of the donors were unremarkable. As the suboptimal donor corneal tissue may escape the standard screening protocols, eye banks should consider adding AS-OCT imaging for screening donor corneal tissue before transplantation.

Corneal transplantation in the modern era

Corneal blindness is one of the major causes of reversible blindness, which can be managed with transplantation of a healthy donor cornea. It is the most successful organ transplantation in the human body as cornea is devoid of vasculature, minimizing the risk of graft rejection. The first successful transplant was performed by Zirm, and since then, corneal transplantation has seen significant evolution. It has been possible because of the relentless efforts by researchers and the increase in knowledge about corneal anatomy, improvement in instruments and advancements in technology. Keratoplasty has come a long way since the initial surgeries wherein the whole cornea was replaced to the present day where only the selective diseased layer can be replaced. These newer procedures maintain structural integrity and avoid catastrophic complications associated with open globe surgery. Corneal transplantation procedures are broadly classified as full-thickness penetrating keratoplasty and partial lamellar corneal surgeries which include anterior lamellar keratoplasty [sperficial anterior lamellar keratoplasty (SALK), automated lamellar therapeutic keratoplasty (ALTK) and deep anterior lamellar keratoplasty (DALK)] and posterior lamellar keratoplasty [Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK)] broadly.

Penetration of 0. 3% ciprofloxacin, 0. 3% ofloxacin, and 0. 5% moxifloxacin into the cornea and aqueous humor of enucleated human eyes

We aimed to quantify the penetration of ciprofloxacin, ofloxacin, and moxifloxacin into the cornea and aqueous humor of cadaver eyes. A total of 60 enucleated eyes, not eligible for corneal transplantation, were divided into three groups and immersed in commercial solutions of 0.3% ciprofloxacin, 0.3% ofloxacin, or 0.5% moxifloxacin for 10 min. Whole corneas and samples of aqueous humor were then harvested and frozen, and drug concentrations analyzed by liquid chromatography tandem mass spectrometry. The mean corneal concentration of moxifloxacin was twice as high as ofloxacin, and the latter was twice as high as ciprofloxacin. The mean concentration of moxifloxacin in the aqueous humor was four times higher than the other antibiotics, and the mean concentrations of ciprofloxacin and ofloxacin were statistically similar. The amount of drug that penetrated the anterior chamber after a 10-min immersion was far below the safe limit of endothelial toxicity of each preparation. Moxifloxacin demonstrated far superior penetration into the cornea and anterior chamber of cadaver eyes compared to ciprofloxacin and ofloxacin. One should not expect endothelial toxicity with the commercial eye drops of ciprofloxacin, ofloxacin, and moxifloxacin that reach the anterior chamber through the cornea.

Intrastromal corneal ring segments delay corneal grafting in patients with keratoconus / Segmentos de anéis intracorneanos protelam o transplante de córnea em pacientes com ceratocone

ABSTRACT Purpose: To assess the impact of intrastromal corneal ring segments (ICRS) as a surgical alternative to corneal grafting in patients with keratoconus who were scheduled for a corneal transplant. Methods: This single-surgeon, single-center, retrospective, observational case series study included 19 eyes of 18 patients (mean age, 23.36 ± 6.22 years) with a confirmed diagnosis of keratoconus. These patients were enrolled from the State of Goiás, Brazil corneal graft waiting list. Following extensive pre-operative testing, including the measurement of best-corrected visual acuity (BCVA), applanation tonometry, biomicroscopy, funduscopy, pachymetry, and corneal topography, patients were implanted with Keraring® ICRS. Patients underwent clinical examination at postoperative days 1, 7, 30, 90, and 180 and were examined again 2 years following surgery. Results: At the 2-year cut-off following ICRS implantation (mean follow-up, 28.72 ± 4.71 months), there was a statistically significant improvement in BCVA (logMAR) from 0.59 ± 0.35 preoperatively to 0.35 ± 0.45 postoperatively ( p <0.01). Three of 19 eyes (15.8%) still required keratoplasty. In the remaining patients (84.2%), BCVA was managed with spectacles (52.6%) or contact lenses (31.6%). One patient developed infectious keratitis, requiring removal of ICR at the first postoperative visit. Conclusion: ICRS implantation may be a surgical alternative to keratoplasty in patients with keratoconus. This procedure may delay or even eliminate the need for keratoplasty in such patients.

RESUMO Objetivo: Avaliar o impacto do implante de anéis corneanos intraestromais como alternativa cirúrgica à ceratoplastia, em pacientes com ceratocone previamente inscritos na fila de espera para transplante de córnea. Métodos: Este estudo unicêntrico, retrospectivo, observacional analisou prontuários de 19 olhos de 18 pacientes (idade média de 23,36 ± 6,22) com diagnóstico de ceratocone, incluídos na lista de espera para transplante de córnea do estado de Goiás, Brasil. Após realização de exame oftalmológico completo pré-operatório, incluindo acuidade visual (AV) corrigida, tonometria de aplanação, biomicroscopia, fundoscopia, paquimetria e topografia corneana, os pacientes foram submetidos a cirurgia para implante de anel intracorneano Keraring®. Os mesmos foram submetidos a exame oftalmológico no 1o, 7o, 30o, 90o, 180o dias de pós-operatório, e também após 2 anos da cirurgia. Resultado: Após a visita final de 2 anos de acompanhamento (média de seguimento de 28,72 ± 4,71 meses), houve melhora estatisticamente significativa da AV corrigida (logMAR): 0,59 ± 0,35 no pré-operatório para 0,35 ± 0,45 do pós-operatório ( p <0,01). Três dos 19 olhos (15,8%) permaneceram com a indicação de ceratoplastia. A conduta para os demais (84,2%) foi correção óptica com óculos (52,6%) ou lente de contato (31,6%). Um paciente evoluiu com ceratite infecciosa no pós-operatório, tendo seus anéis removidos. Conclusão: O implante de anéis intraestromais mostrou ser uma alternativa eficaz ao transplante de córnea nesta série de casos. Esse procedimento pode ajudar a retardar ou eliminar a necessidade de indicação de ceratoplastia em pacientes com ceratocone.

Donor and tissue profile of a community eye bank in Eastern India.

Purpose: The purpose of this study is to analyze the donor and tissue profile of a community eye bank in Eastern India. Materials and Methods: Eye bank records were analyzed for the period July 2007-June 2011. Variables analyzed included donor demographics (age, gender, and ethnicity), donor cause of death, consent for recovery, death‑to‑preservation interval, preservation‑to‑utilization interval, endothelial cell density (ECD), corneal suitability for transplantation, and corneal tissue utilization. Results: During this study period, 743 corneal tissues were retrieved from 373 donors (male:female = 263:110). The mean age of donors was 52 ± 21 years (range: 3-95 years). The most common donor age group was 41-50 and 71- 80 years. Most of the donors belonged to one religious faith (99%). The most common causes of death were cardiorespiratory failure (34%) followed by road traffic accident (30%). Majority donors were motivated (n = 320; 86%), and remaining (n = 53; 14%) were voluntary. Most of the consents were given by sons or daughters of the deceased (45%) followed by siblings (18%). Mean death‑to‑preservation interval was 3.9 ± 1.9 h. Mean preservation‑to‑utilization interval was 56.0 ± 24.4 h. The mean ECD of donor corneal tissue was 2857 ± 551 cells/mm2 and the median value was 2898 cells/mm2. Of harvested corneas 556 (75%) corneal tissues were utilized. The most common causes of nonutilization were septicemia in donor (n = 56; 30%) and poor quality of tissue (n = 55; 30%). Conclusions: Although, there is significant corneal tissue utilization, there is a need for increased awareness among people in order to augment voluntary donations.