Corneal Transplantation Activity Over 7 Years: Changing Trends for Indications, Patient Demographics and Surgical Techniques From the Corneal Transplant Epidemiological Study (CORTES)

Changing indications for and trends of keratoplasty in a tertiary comprehensive hospital in northern part of China from 2002 to 2021: a 20-year review

OBJECTIVE

To investigate indications and surgical procedures of keratoplasty in a tertiary comprehensive hospital in northern part of China over a 20-year period.

METHODS

All patients undergoing keratoplasty between January 1, 2002 to December 31, 2021 in a tertiary comprehensive hospital in northern part of China were retrospectively reviewed. The annual proportion of keratoplasty indications and surgical procedures was recorded and analyzed.

RESULTS

A total of 8266 keratoplasty procedures were included. Leading indications were keratoleukoma (n = 2108, 25.50%), followed by regraft (n = 1453 ,17.58%), corneal endothelial dysfunction (n = 1085, 13.13%), and keratoconus (n = 922,11.15%). A decreasing trend was observed for keratoleukoma (P < 0.01) and an increasing trend for corneal endothelial dysfunction (P < 0.01), regraft (P = 0.012), corneal limbal dermoids (P < 0.01) and congenital corneal opacity (P < 0.01). From 2002 to 2021, the proportion of penetrating keratoplasty (PK) had decreased from 73.95% (2002 to 2006) to 53.49% (2017 to 2021). On contrary, anterior lamellar keratoplasty (ALK) (459-705, 26.05-31.96%, P = 0.034) and endothelial keratoplasty (EK) (0-321, 0.00-14.55%, P < 0.01) became more prevalent from 2002 to 2021. For cases with corneal endothelial dysfunction, EK became the preferred technique (74.72%) in the recent 5 years.

CONCLUSION

Over the past 20 years, keratoleukoma and regraft have been the leading indications for keratoplasty. A noticeable shift in surgical preference from PK to DSAEK and ALK is evident, with key indications for keratoplasty including keratoleukoma, regraft, limbal dermoids, endothelial dysfunction, and keratoconus, respectively.

Reliability and reproducibility of an Italian questionnaire on "Knowledge of high social impact Eye Diseases" (KED-IT)

Background

Health literacy plays an important role in public health. Although this has been demonstrated in the field of ophthalmology, there are very few specific instruments available to assess eye health literacy. This work aims to develop an Italian questionnaire on knowledge of eye diseases (Knowledge on Eye Disease, Italian version; KED-IT) and to evaluate its reliability and reproducibility. The KED-IT focuses on diseases with high social impact, specifically glaucoma, macular degeneration, diabetic retinopathy and keratoconus, which is the main cause of corneal transplant in Italy.

Methods

A cross-sectional study was conducted. The KED-IT was self-administered by the study participants twice. The interval between each administration (T0 and T1) was 5 to 8 days. Reliability was assessed using the KR-20 coefficient. The test-retest Cohen's Kappa coefficient was estimated to measure the stability and reproducibility of the results obtained between T0 and T1.

Results

A total of 60 subjects participated in the study. The response rate at T1 was 92%. The KR-20 reliability coefficient of the 14-item KED-IT questionnaire was good with a value of 0.878. The Cohen's kappa value for all 14 items of the KED-IT questionnaire was k = 0.747, indicating good agreement.

Conclusions

The KED-IT is the first specific ophthalmic knowledge questionnaire validated in the Italian language and we hope that it may be a starting point for the study of eye health literacy in the Italian population.

Andalusian Public Eye-Banks: a decade of continuous improvement

OBJECTIVES

To show donation data, number of keratoplasties and the changes in transplant indications and techniques that occurred in Andalusia in the period from 2013 to 2022.

MATERIALS AND METHODS

The present work is a retrospective and descriptive study that included all keratoplasties performed between January 2013 and December 2022 in Andalusia, as well as the evolution of the cornea donation and transplant activity of the public and private hospitals pertaining to the waiting list management system of the Public Health System of Andalusia. Transplants performed in private centers with corneas from outside Andalusia were excluded.

RESULTS

Cornea donation activity in Andalusia in the decade 2013-2022 has experienced a growth of more than 126%, while overall transplant activity has increased by 157% in public hospitals. Penetrating keratoplasty has decreased from 83% in 2013 to 43% in 2022, while lamellar techniques have increased from 17% to 57% in this same period. Since 2018, more lamellar transplants are performed than penetrating transplants. Regarding indications, endothelial conditions already represent the first cause of transplantation. In 2022 alone, the public Andalusian Eye Banks evaluated 1,054 corneas and prepared 281 endothelial grafts.

CONCLUSION

In the decade from 2013 to 2022 in Andalusia there has been an increase in donation activity and the number of keratoplasties. The public Eye Banks implementation in this period has played a key role in the widespread adoption of lamellar keratoplasty techniques and has enabled the transition to perform a greater number of lamellar keratoplasties compared to penetrating keratoplasty.

Effect of Nd:YAG laser capsulotomy on graft endothelium after penetrating keratoplasty

BACKGROUND

To investigate the safety of Nd:YAG laser capsulotomy in eyes with Penetrating Keratoplasty (PK) and its impact on corneal endothelium as well as graft survival.

METHODS

Thirty patients who underwent Nd: YAG laser capsulotomy after PK and 30 pseudophakic control eyes were included in this prospective study. Endothelial cell density (ECD), hexagonality (HEX), coefficient of variation (CV), central corneal thickness (CCT), and the change of these values during follow-up measured at the 1st hour, first week, and first month after the laser and the data were compared between groups.

RESULTS

The mean time passed between the PK procedure and the subsequent YAG laser procedure was i.e. of YAG laser after PK was 30.5 ± 15.2 months (range 6 to 57 months). Baseline ECD was 1648.2 ± 669.77 cells/mm² in the PK group and 2008.27 ± 347.42 cells/mm² in the control group. In the first month, ECD was 1545.2 ± 639.35 cells/mm² in the PK group and 1979 ± 350.95 in the control group. The loss was significantly higher in PK group (-103 ± 153.67 cells/mm²) (6.25%) compare to the control group (-28.73 ± 82.31 cells/mm²) (1.44%) (p = 0.024). A significant increase in CV was observed in the PK group, and not in the control group (p = 0.008, p = 0.255, respectively). There were no significant changes in HEX and CCT values in either group.

CONCLUSION

Nd:YAG laser provides a significant increase in visual acuity in first month in patients with PK with no significant harmful effect on graft transparency. Endothelial cell density measurements during follow-up will be beneficial.

Clearing the path to vision restoration: an analysis of attitudes and associated factors towards cornea donation in Syria

OBJECTIVE

This study aims to assess attitudes and associated factors towards cornea donation among visitors of a main public hospital in Damascus. Findings of this study can contribute to the development of effective donation campaigns and applying cornea donation in Syria.

METHODS

This cross-sectional study included individuals who were above 18 years old and were visitors of Al-Mouwasat University Hospital in Damascus, Syria. Data were gathered using a questionnaire administered through face-to-face interviews with the participants. A validated questionnaire was used and consisted of three sections: demographic information, awareness assessment and evaluation of participants' attitudes towards corneal donation. Associations between participants' demographics and variables were tested using χ² test, and a p value of <0.05 was considered significant.

RESULTS

637 participants were randomly interviewed. 70.8% of the sample were female and 45.7% have heard about cornea donation. 68.3% of the participants accepted donation of their cornea after death, but this decreased to 56.2% when it comes to donation from relatives after their death. The main reasons for refusing and accepting cornea donation were religious beliefs (10.8%) and intention to help others (65.8%), respectively. Women were more likely to accept donation after death than men (71.4% vs 60.8%, p=0.009). Finally, acceptance of cornea donation would increase if participants lived in a more developed country (71.7% vs 68.3%).

CONCLUSION

Despite the high willingness, corneal donation in Syria is still not enough. Corneal donation requires an ensured donation system that supports and organises the processes, a simplified education about the importance of donation, and clarifying the right instructions of religion.

Trends in Keratoplasty Procedures During 2 Decades in a Major Tertiary Referral Center in Finland: 1995 to 2015

PURPOSE

The purpose of this study was to analyze trends in number, age-adjusted frequency, and type of keratoplasty in a major tertiary referral center, relative to patient and graft characteristics.

METHODS

A retrospective registry study of 1574 patients who in 1995 to 2015 underwent keratoplasty in the Helsinki University Eye Hospital (HUEH). Graft type and sequence, patient characteristics, and date of surgery were recorded. Main outcome measures were annual number, type, and age-adjusted frequency of keratoplasty; patient and graft characteristics; graft procurement; and national population-adjusted frequency of keratoplasty.

RESULTS

In HUEH, from 1995 to 2015, a total of 2191 keratoplasties were performed with 48% of the grafts procured intramurally; 76% were primary and 24% regrafts. The age-adjusted frequency of primary penetrating keratoplasty decreased by 52% from 0.96 to 0.46 per 100,000. The corresponding frequency of primary Descemet stripping automated endothelial keratoplasty increased by 367% from 0.3 to 1.4 after 2006, finally accounting for 68% of primary grafts. Men underwent primary penetrating keratoplasty (median 48 vs. 67 yrs, P = 0.0001) and anterior lamellar keratoplasty (median 37 vs. 46 yrs, P = 0.0015) at a younger age than women. Interval to the first regraft was comparable between sexes (median 2.2 vs. 1.9 yrs, respectively, P = 0.17). The national median population-adjusted frequency of keratoplasties was 3.2 per 100,000 from 2009 to 2015, and HUEH accounted for a median of 69% of them.

CONCLUSIONS

The increased frequency of keratoplasty in HUEH resulted from rapid adoption of Descemet stripping automated endothelial keratoplasty after 2006 and was facilitated by centralizing graft procurement to HUEH and the National Cell and Tissue Center Regea.

Indications and techniques of corneal transplants performed in one center in Southern Poland, in the years 2001–2020

Purpose

The study aimed to evaluate changes over a period of time in techniques and indications for corneal transplantation in a single center in Poland.

Methods

Retrospective analysis of corneal transplants performed at the Ophthalmology Department of the District Railway Hospital in Katowice in 2001–2020. Data on indications and surgical technique were collected.

Results

A total of 3021 corneal transplantations were performed in the years 2000–2020. The most common technique was penetrating keratoplasty (69,54%), then lamellar grafts—both anterior and posterior (19,63%), and limbal grafts (10,82%). Only in 2007 the number of lamellar keratoplasties exceeded the number of penetrating grafts and accounted for 108 (54,55%), including 85 (42,93%) of Descemet Stripping Automated Endothelial Keratoplasty. The only noticeable trend in changing techniques was a decrease in the number of performed deep anterior lamellar keratoplasties (r 2 = -0.21) over the last seven years. Main indications included bullous keratopathy (23,22%), following keratoconus (18,59%), leukoma (14,67%), keratitis and perforation (14,3%), Fuchs dystrophy (11,4%), and regrafts (7,22%). Leukoma and bullous keratopathy as an indications for corneal transplant have been declining over the years (r2 = 0.60 and r2 = 0.30 respectively). Consecutively, indications such as fuchs dystrophy, regraft and keratitis perforation have increased (r2 = 0.05, r2 = 0.50, r2 = 0.33)

Conclusions

The number of keratoplasties gradually increased from 2001 to 2020. It could be possible that the development and spread of new therapeutic alternatives, like corneal cross-linking and scleral lenses, have contributed to the decrease in deep anterior lamellar keratoplasty performed. There was an increasing trend in the percentage of penetrating keratoplasties for failed grafts, Fuchs dystrophy and infectious keratitis.

Trends in Corneal Transplantation in a Tertiary Hospital in Brazil

PURPOSE

The purpose of this study was to analyze the evolving trends of surgical techniques and indications of corneal transplantation (CT) at a tertiary hospital in Brazil.

METHODS

The medical records of all patients who underwent CT at the Hospital Oftalmológico de Sorocaba (Sorocaba Eye Hospital) from the Banco de Olhos de Sorocaba (Sorocaba Eye Bank) group in Sorocaba, Brazil, from January 1, 2012, to December 31, 2019, were analyzed. Data regarding age, sex, transplant indication, and surgical technique were collected.

RESULTS

A total of 16,250 CTs were performed. There was a statistically significant decreasing trend of keratoconus-related CT ( P < 0.0001), with rates dropping from 41.7% among all CTs in 2012 to 25.5% in 2019. Penetrating keratoplasty, anterior lamellar keratoplasty, and endothelial keratoplasty (EK) accounted for 59.3%, 27.1%, and 7.8% of the CTs performed in 2012 and 33.3%, 16.4%, and 39.9% in 2019, respectively. A statistically significant decreasing trend was observed for penetrating keratoplasty ( P < 0.0001) and anterior lamellar keratoplasty ( P < 0.0001), whereas EK showed a statistically significant increasing trend during the period ( P < 0.0001). Among EKs, Descemet membrane EK increased statistically significantly from 12.8% in 2012 to 74.4% in 2019 ( P < 0.0001).

CONCLUSIONS

This study shows relevant evolving trends in indications and preferred CT techniques in a tertiary hospital in Brazil.

Optimization of the Ocular Surface Through Treatment of Ocular Surface Disease Before Ophthalmic Surgery: A Narrative Review

Ocular surface disease commonly exists in individuals requiring ophthalmic surgery and may compromise the structure and function of ocular surface components. Ophthalmic surgery may further affect the ocular surface by injuring the epithelium and sensory nerves, disrupting the tear film, or causing local inflammation. Medical management of ocular surface disease prior to ophthalmic surgery aids in reducing inflammation, resolving infection, improving epithelial pathology, stabilizing the tear film, and easing patient symptoms, promoting positive long-term outcomes and minimizing the incidence of postoperative complications. This review summarizes frequently encountered ocular surface diseases and available preoperative medical management options, discusses common ophthalmic surgeries and their effects on the ocular surface, examines potential postoperative complications, and defines recommendations for postoperative ocular surface maintenance.

The Neuropeptide Alpha-Melanocyte-Stimulating Hormone Is Critical for Corneal Endothelial Cell Protection and Graft Survival after Transplantation

Corneal transplantation is the most common form of tissue transplantation. The success of corneal transplantation mainly relies on the integrity of corneal endothelial cells (CEnCs), which maintain tissue transparency by pumping out excess water from the cornea. After transplantation, the rate of CEnC loss far exceeds that seen with normal aging, which can threaten sight. The underlying mechanisms are poorly understood. Alpha-melanocyte-stimulating hormone (α-MSH) is a neuropeptide that is constitutively found in the aqueous humor with both cytoprotective and immunomodulatory effects. The curent study found high expression of melanocortin 1 receptor (MC1R), the receptor for α-MSH, on CEnCs. The effect of α-MSH/MC1R signaling on endothelial function and allograft survival in vitro and in vivo was investigated using MC1R signaling-deficient mice (Mc1re/e mice with a nonfunctional MC1R). Herein, the results indicate that in addition to its well-known immunomodulatory effect, α-MSH has cytoprotective effects on CEnCs after corneal transplantation, and the loss of MC1R signaling significantly decreases long-term graft survival in vivo. In conclusion, α-MSH/MC1R signaling is critical for CEnC function and graft survival after corneal transplantation.

Trends in Corneal Transplantation and Characteristics of Donors in the Chongqing Eye Bank, China: A Retrospective Study, 1999-2018

Aim: This study aimed to analyze corneal transplantation trends and voluntary donor characteristics at the Chongqing Eye Bank in China.

Methods: We retrospectively reviewed and analyzed data from January 1, 1999, to December 31, 2018, covering 5,397 preregistered voluntary donors, 1,955 actual donors, 3,910 donated tissues, and 2,374 corneal transplantations.

Results: The 5,397 preregistered donors included 13 ethnic groups, with an overall mean age of 39.6 years (SD 21.5) and 3,010 were women (55.8%). The most prevalent education level was college and above (2,546, 47.2%), and the most common ethnic group was Han (5,335, 98.85%). Of the 1,955 actual donors, the male-to-female ratio was 3.3, and the mean age was 57.1 (SD 23.0 years). Based on population size in 2018, Jiangbei county was the most active in donation willingness, with ~60 × 10⁻⁶ per capita, and the Yuzhong county was the most active in cornea donations, with ~451 × 0⁻⁶ per capita. Of the 3,910 donated corneas, 2,540 (65.0%) were clinically used. Of those not used, 978 (71.4%) were rejected for poor corneal quality. The 2,374 (93.5%) corneal transplantation procedures were done at the Department of Ophthalmology of the First Affiliated Hospital of Chongqing Medical University and the rest (n = 166, 6.5%) were performed in other centers. Of those 2,374 corneal transplantations, there were 1,671 penetrating keratoplasty (70.39%), 700 anterior lamellar keratoplasty (29.49%), and three corneal endothelial transplantations in our center (0.13%). The number of annual corneal transplantations increased by nearly 10 times, from 35 cases in 1999 to 327 cases in 2018. Among them, cases of penetrating keratoplasty and anterior lamellar keratoplasty increased from 27, and eight cases in 1999 to 230 and 94 cases in 2018, respectively. Infectious keratitis (37.0%) was the leading indication for keratoplasty, followed by corneal scar (19.8%). Over the study period, corneal scars dropped from the first (41.1% in 1999–2003) to the second indication (20.5% in 2014–2018), while infectious keratitis advanced to take the lead, ranging from 12.2% in 1999–2003 to 26.3% in 2014–2018.

Conclusion: Our study reports corneal donation and transplantation trends in Chongqing over 20 years, showing that infectious keratitis is a leading indication for keratoplasty and that penetrating keratoplasty and anterior lamellar keratoplasty show upward trends. The analysis further suggests that a potential preregistered cornea donor is a female Han, with a higher education level.

Predictors of Receiving Keratoplasty for Keratoconus

PURPOSE

To identify sociodemographic factors and comorbid conditions associated with receiving keratoplasty for keratoconus (KCN).

DESIGN

Retrospective, cross-sectional study.

METHODS

Health records of KCN patients <65 years of age from 2011 to 2018 were obtained from the IBM MarketScan Database. A multivariable model adjusted for potential confounders was used to examine factors associated with the risk of receiving keratoplasty.

RESULTS

Of 42,086 total patients with KCN identified, 1282 (3.0%) patients had keratoplasty to treat KCN. In the fully adjusted analysis, female sex (odds ratio [OR] 0.87 [95% confidence interval {CI} 0.78-0.98]) and living in metropolitan areas (OR 0.75 [95% CI 0.63-0.90]) were associated with lower odds of receiving keratoplasty. Compared with individuals 10 to 19 years of age, those 20 to 29 years of age (OR 1.77 [95% CI 1.31-2.41]) and 30 to 39 years of age (OR 1.61 [95% CI 1.19-2.17]) were more likely to have keratoplasty, while individuals in the older age groups (50-64 years of age) did not show statistically significant associations. Conditions associated with higher odds of receiving keratoplasty were corneal hydrops (OR 4.87 [95% CI 4.07-5.82]), Leber congenital amaurosis (OR 2.41 [95% CI 1.02-5.71]), sleep apnea (OR 1.46 [95% CI 1.25-1.71]), diabetes mellitus (OR 1.32 [95% CI 1.13-1.54]), and depression (OR 1.22 [95% CI 1.03-1.44]). Conditions associated with lower odds were previous contact lens usage (OR 0.61 [95% CI 0.50-0.74]) and a history of glaucoma (OR 0.60 [95% CI 0.49-0.73]).

CONCLUSIONS

This analysis of a large sample of patients with KCN reveals previously unidentified risk factors associated with receiving keratoplasty including Leber congenital amaurosis, depression, and diabetes. Future research should examine if young patients with these conditions may benefit from more frequent follow-up and/or early crosslinking to reduce the need for subsequent keratoplasty.

Trends of Corneal Transplantation in Adults from 2010 to 2019 in East China: A 10-Year Experience

INTRODUCTION

The aim of the study was to provide an overview of trends in the indications and surgical techniques for corneal transplantation in adults in East China from 2010 to 2019.

METHODS

The medical charts of all patients (aged ≥18 years old) undergoing keratoplasty at the Eye, Ear, Nose and Throat Hospital of Fudan University between January 2010 and December 2019 were retrospectively reviewed. The indications for keratoplasty and the surgical techniques were collected.

RESULTS

A total of 2,929 cases were included. Acquired nontraumatic corneal diseases (n = 1,927, 65.8%) have been the leading indication for corneal transplantation during the past decade. Although infectious keratitis was still the leading indication among acquired nontraumatic diseases, its absolute number and proportion gradually decreased during this decade (p < 0.001). In contrast, the proportion of endothelial dysfunction/bullous keratopathy increased from 7.8% in 2010 to 12.4% in 2019 (p = 0.029). Penetrating keratoplasty (PKP) has been the predominant surgical technique (n = 1,854, 63.3%), followed by deep anterior lamellar keratoplasty (DALK) (n = 361, 12.3%) and endothelial keratoplasty (EK) (n = 305, 10.4%). Nevertheless, the proportion of PKP decreased from 77.6% in 2010 to 56.9% in 2019 (p = 0.002) and was gradually replaced by DALK (from 7.8% to 16.3%, p < 0.001) and EK (from 3.4% to 10.4%, p = 0.009).

CONCLUSIONS

Over the past decade, infectious keratitis and endothelial dysfunction/bullous keratopathy have been the leading indications for keratoplasty in adults. Preferred surgical techniques for keratoplasty have been shifting from PKP to more customized lamellar keratoplasties.

Recent indications of endothelial keratoplasty at a tertiary eye care center in South India

PURPOSE

To describe the patient demographics and recent clinical indications of endothelial keratoplasty (EK) in patients presenting to a tertiary eye care center in India.

METHODS

This cross-sectional hospital-based study included 2,182 patients who underwent EK between Jan 2016 and Dec 2019 (4 years period). The data were collected using an electronic medical record system.

RESULTS

Overall, 2,632 eyes of 2,182 patients underwent EK during the study period. Median age was 62 (IQR: 48-70) years and adults (94.45%) comprised most of the cohort. More commonly, the patients were male (55.59%) and from the higher socioeconomic strata (67.51%). The corneal signs included corneal edema (70.93%), corneal scarring (29.60%), corneal vascularization (16%) and guttae (12.88%). The major indications of EK were post-cataract surgery corneal edema in 1331 (50.57%) patients, endothelial dystrophy in 537 (20.4%) patients, failed graft in 535 (20.33%) patients causing a vision impairment of > 20/400-20/1200 in about a half (45.55%) of the patients. Descemet stripping endothelial keratoplasty (DSEK) and Descemet membrane endothelial keratoplasty (DMEK) were performed in 2075 (78.84%) and 557(21.16%) patients, respectively.

CONCLUSION

EK is commonly performed during the sixth decade of life and in males. The most performed procedure is DSEK. The commonest indication was post-cataract surgery corneal edema.

Corneal transplantation activity in Catalonia, Spain, from 2011 to 2018: Evolution of indications and surgical techniques

Purpose

To report corneal transplant activity carried out in Catalonia (Spain) and the evolving indications for keratoplasty over an 8-year period.

Methods

Annual reports from the Catalan Transplant Organization, Spain, on corneal graft indications and techniques from 2011 to 2018 were reviewed.

Results

A total of 9457 keratoplasties were performed in Catalonia, from January 2011 to December 2018. The most frequent indications were bullous keratopathy (BK; 20.5%), Fuchs endothelial dystrophy (FED; 17.9%), re-graft (13.7%), and keratoconus (11.3%). Penetrating keratoplasty (PKP) accounted for 63.4% of all performed keratoplasties. Since the introduction of eye bank precut tissue for Descemet stripping automated endothelial keratoplasty (DSAEK) in 2013 and for Descemet membrane endothelial keratoplasty (DMEK) in 2017 the number of endothelial keratoplasties has drastically increased. An increasing trend of posterior lamellar techniques over the total of keratoplasties was found (p<0.001). Endothelial keratoplasties for different endothelial diseases indications (BK, FED, and re-graft), also showed and increasing trend (p<0.001). DMEK is the technique with the highest increase (statistically significantly different from linearity) over other endothelial keratoplasties in FED (p<0.001) but not in BK (p = 0.67) or re-grafts (p = 0.067).

Conclusion

Endothelial diseases represented the top indication for keratoplasty over the 8-year period. PKP is still the most used technique in Catalonia, but endothelial keratoplasties and especially DMEK showed a significant increasing trend over the last years. This is congruent with the main rationale nowadays for keratoplasties: to customize and transplant as less tissue as possible. Therefore, the availability of precut tissue could have definitely enforced such approach.

Pediatric keratoconus - Current perspectives and clinical challenges

Keratoconus is an ectatic corneal disease characterized by progressive stromal thinning, irregular astigmatism, and defective vision. It can be unilateral or bilateral with asymmetric presentation. It starts at puberty and either progresses rapidly to an advanced stage of the disease or stops in case of delayed onset and slow progression. Pediatric keratoconus is more aggressive than in adults and the management protocols differ because of various rationales such as accelerated progression, advanced stage of disease at the time of diagnosis and co-morbidities. It poses a burden to the society as it affects the quality of life, social, and educational development in children. Hence early diagnosis, recognition of progression, and timely intervention with collagen crosslinking is imperative to arrest the worsening. Association with systemic syndromes and ocular comorbidities can be of concern in pediatric keratoconus. Severe ocular allergy when associated hastens progress and complicates timely intervention of crosslinking treatment and compliance to contact lens wear. Keratoplasty in pediatric keratoconus has good outcomes but can encounter frequent suture-related concerns. This article discusses the epidemiology, etiopathogenesis, clinical challenges, and current perspectives of management of pediatric keratoconus.

[Comparison of visual acuity, complications and patient satisfaction between outpatient and inpatient keratoplasty surgery]

INTRODUCTION

Our objective in this work was to compare visual acuity, complication rate, rate of unplanned visits in the month following the procedure, and patient satisfaction between patients who received a corneal transplant as an outpatient or inpatient.

PATIENTS AND METHODS

Our work focused on 19 patients (6 inpatients and 13 outpatients), who had undergone unilateral keratoplasty between May 2018 and December 2018. The indications for corneal transplant were keratoconus, Fuchs dystrophy and graft rejection.

RESULTS

All patients who were followed for at least one month had an improvement in their VA. There were on average as many postoperative consultations in the inpatient group as in the outpatient group. Complications occurred in 77% of inpatients versus 40% of outpatients. The rate of consultations in the month following the operation was similar in both groups. Patients were satisfied with outpatient management.

DISCUSSION

No similar studies have been conducted to our knowledge. This preliminary work is limited by the small number of patients and questionnaires received and the length of follow-up. The criteria for outpatient care are very important to limit complications. For corneal transplantation, hospitalisation is most often performed with an average stay of 2 to 5 days. Outpatient management seems, according to our preliminary work, to be able to be extended into more centres without changing the postoperative follow-up or increasing the rate of complications, allowing lower cost and patient satisfaction.

CONCLUSION

The previous lack of this type of study, as well as the encouraging results of this work, open the way to larger scale prospective comparative as well as medico-economic studies.

Fuchs endothelial corneal dystrophy: The vicious cycle of Fuchs pathogenesis

Fuchs endothelial corneal dystrophy (FECD) is the most common primary corneal endothelial dystrophy and the leading indication for corneal transplantation worldwide. FECD is characterized by the progressive decline of corneal endothelial cells (CECs) and the formation of extracellular matrix (ECM) excrescences in Descemet's membrane (DM), called guttae, that lead to corneal edema and loss of vision. FECD typically manifests in the fifth decades of life and has a greater incidence in women. FECD is a complex and heterogeneous genetic disease where interaction between genetic and environmental factors results in cellular apoptosis and aberrant ECM deposition. In this review, we will discuss a complex interplay of genetic, epigenetic, and exogenous factors in inciting oxidative stress, auto(mito)phagy, unfolded protein response, and mitochondrial dysfunction during CEC degeneration. Specifically, we explore the factors that influence cellular fate to undergo apoptosis, senescence, and endothelial-to-mesenchymal transition. These findings will highlight the importance of abnormal CEC-DM interactions in triggering the vicious cycle of FECD pathogenesis. We will also review clinical characteristics, diagnostic tools, and current medical and surgical management options for FECD patients. These new paradigms in FECD pathogenesis present an opportunity to develop novel therapeutics for the treatment of FECD.

[Change of corneal radii after Descemet membrane endothelial keratoplasty measured by optical coherence tomography and Scheimpflug tomography]

BACKGROUND

The aim of the study was to compare the measurement of corneal radii using Scheimpflug tomography (Pentacam®, Oculus, Wetzlar, Germany) and optical coherence tomography (OCT, Optovue® XR-Avanti, Fremont, CA, USA) in eyes of patients with Fuchs' endothelial dystrophy (FED) before and after Descemet membrane endothelial keratoplasty (DMEK).

MATERIAL AND METHODS

In a retrospective analysis 35 eyes with (FED) that underwent DMEK were included. Pentacam® and Optovue® corneal measurements were performed preoperatively and at least 3 months postoperatively. The four primary objectives were the radii of the anterior and posterior corneal surfaces, the corneal thickness and the posterior to anterior corneal curvature radii ratio. The change in the primary targets after DMEK was analyzed and the measurement results of both methods were compared. A Bland-Altman plot was created to graphically illustrate the correlation between the two measuring methods.

RESULTS

A significant decrease in corneal thickness was observed after DMEK with both methods. The radii of the anterior corneal surface, measured with Scheimpflug as well as with OCT showed no significant changes after surgery, while the radii of the posterior corneal surface significantly decreased (Pentacam®: preoperative = 7.24 mm ± 0.99 mm; postoperative = 6.38 mm ± 0.40 mm, P < 0.001; Optovue®: preoperative = 7.63 mm ± 1.43 mm; postoperative = 6.57 mm ± 0.43 mm, P < 0.001). The Bland-Altman plots of all primary objectives showed a better agreement postoperatively compared to the preoperative measurements.

CONCLUSION

Both Scheimpflug and OCT showed a significant decrease in the radius of the posterior corneal surface after DMEK. The postoperative measurements showed a higher agreement between the devices than those performed preoperatively.

Changing trends in penetrating keratoplasty indications at a tertiary eye care center in Budapest, Hungary between 2006 and 2017

AIM

To analyze the changing trends in penetrating keratoplasty (PKP) indications.

METHODS

This retrospective study included all patients with PKP between 2006 and 2017. Patients were classified using histological diagnoses. Our groups were as the following: pseudophakic or aphakic bullous keratopathy, regraft, acute necrotizing and ulcerative keratitis, keratoconus, Fuchs' dystrophy, corneal dystrophy other than Fuchs', corneal scar, other diagnoses and failed endothelial keratoplasty graft. Additionally, two different time-periods (2006-2012 and 2013-2017) were analysed.

RESULTS

Totally 1721 histological analyses of 1214 patients were available for review. The diagnoses were pseudophakic or aphakic bullous keratopathy in 487 (28.3%), regraft in 443 (25.7%), acute necrotizing and ulcerative keratitis in 313 (18.2%), corneal scar in 153 (8.9%), keratoconus in 140 (8.1%). Fuchs' dystrophy in 61 (3.5%), corneal dystrophy other than Fuchs' in 46 (2.7%), other diagnoses in 44 (2.6%) and failed endothelial keratoplasty graft in 34 (2.0%) cases. From the first to the second analysed time-period, incidence of acute necrotizing and ulcerative keratitis, corneal scar, Fuchs' dystrophy increased (P≤0.032 for all) and incidence of keratoconus significantly decreased (P=0.015).

CONCLUSION

Pseudophakic or aphakic bullous keratopathy is the leading indication for PKP, followed by regraft and acute necrotizing and ulcerative keratitis.

Three-Year Outcomes of Tri-Folded Endothelium-In Descemet Membrane Endothelial Keratoplasty With Pull-Through Technique

PURPOSE

To assess the 3-year outcomes of tri-folded endothelium-in Descemet membrane endothelial keratoplasty (DMEK) using bimanual pull-through delivery technique.

DESIGN

Interventional case series.

METHODS

In this single-center study, we included 153 consecutive eyes that underwent DMEK for various indications (Fuchs endothelial corneal dystrophy [FECD]: n = 111; bullous keratopathy [BK]: n = 24; and failed graft: n = 18). DMEK grafts were loaded into a disposable cartridge in a tri-folded, endothelium-in configuration and delivered using bimanual pull-through technique. Main outcome measures were graft preparation and unfolding times, best spectacle-corrected visual acuity (BSCVA), endothelial cell density (ECD), and graft survival.

RESULTS

Mean graft preparation time was 5.9 ± 1.1 minutes; and mean graft unfolding time was 2.9 ± 0.9 minutes. Excluding eyes with comorbidities, logarithm of minimum angle of resolution BSCVA improved significantly from baseline preoperative values of 0.92 ± 0.58 to 0.02 ± 0.07 at 1 year (P < .001) and remained stable up to 3 years. Mean postoperative ECD decreased significantly (P < .001) from eye bank values to 1,818 ± 362, 1,675 ± 372, and 1,580 ± 423 cells/mm² at 1, 2, and 3 years, respectively. No significant differences in ECD were observed between eyes with FECD and BK, but ECD was significantly lower in eyes with previous failed graft (P < .05). Three-year cumulative graft survival rate was significantly (P < .001) lower for eyes with previous failed graft (71%) than for FECD (97%) and BK (92%).

CONCLUSIONS

Tri-folded endothelium-in DMEK requires minimal time for graft unfolding, which is the surgical step considered most challenging by corneal surgeons. Visual outcomes and complication rates are not adversely affected by the modification of the surgical technique.

Endothelial Cell Loss After Descemet's Membrane Endothelial Keratoplasty for Fuchs' Endothelial Dystrophy: DMEK Compared to Triple DMEK

PURPOSE

This study compared the outcomes after Descemet's membrane endothelial keratoplasty (DMEK) in pseudophakic patients with the outcomes after DMEK combined with cataract surgery (triple-DMEK) in patients with Fuchs' endothelial dystrophy (FED).

DESIGN

Retrospective, single-institution, interventional, consecutive case series.

METHODS

Outcomes of 114 DMEKs in patients with FED at a minimum of 1-year follow-up were reviewed. A total of 34 eyes (29 patients) were pseudophakic and underwent only DMEK (DMEK-only), and 80 eyes (56 patients) underwent triple-DMEK. Main outcome measurements included endothelial cell loss (ECL), best-corrected visual acuity (BCVA), central corneal thickness (CCT), and complications.

RESULTS

At 1 month, ECL was 25% (±16%) and 35% (±15%) in DMEK-only and triple-DMEK groups, respectively. At 1 year, ECL was 33% (±13%) and 41% (±16%) in DMEK-only and triple-DMEK groups, respectively. There was statistically significantly less ECL after DMEK-only than after triple-DMEK at both 1 month (95% confidence interval [CI]: 1.67-15.02; P = .016) and 1 year (95% CI: 1.06-14.07; P = .034). CCT was significantly lower after DMEK-only than after triple-DMEK at 1 month but not at 1 year. BCVA was excellent and similar in the 2 groups. There were no cases of graft failure. Graft rejection and rebubbling rates were similar in DMEK-only and triple-DMEK groups: rejection occured in 8.8% and 8.75% of cases respectively (P = .50), and rebubbling in 2.9% and 2.5% respectively (P = .44).

CONCLUSIONS

Both the DMEK-only and the triple-DMEK groups had low rebubbling rates and good visual outcomes, but the combined triple-DMEK procedure resulted in significantly greater loss of endothelial cells than DMEK-only surgery at both 1 month and 1 year.

Changing trends in corneal transplantation: a national review of current practices in the Republic of Ireland

BACKGROUND

First Irish National Corneal Transplant Registry report.

AIM

To report about current corneal transplantation practices in Ireland including patient demographics, indications and types of transplant performed and to compare the findings with other developed countries.

METHODS

Nationwide retrospective review of the corneal transplants performed in Ireland between 2016 and 2019.

RESULTS

Overall, 536 keratoplasties were carried out: 256 (47.8%) Penetrating Keratoplasties (PK), 212 (39.6%) Descemet Stripping Automated Endothelial Keratoplasties (DSAEK), 30 (5.6%) Descemet Membrane Endothelial Keratoplasties (DMEK), and 25 (4.7%) Deep Anterior Lamellar Keratoplasties (DALK). The most common indication was Keratoconus (KC, 19%), followed by Fuchs endothelial dystrophy (FED, 18.8%), and Pseudophakic bullous keratopathy (PBK, 17%). KC (34%) and re-grafting (17%) were the leading indications for PK, whereas FED and PBK were the major indications for DSAEK (38% and 33%) and DMEK (67% and 20%), respectively. During the period studied, the number of transplants increased from 11.3 to 14 grafts per month. The number of PKs remained stable, whereas Endothelial Keratoplasties, DSAEK and DMEK, increased (3.8 to 5.6 and 0.2 to 1.6 per month, respectively), becoming the most commonly performed grafts since 2018. Only a small number of DALK were performed.

CONCLUSIONS

Corneal transplantation in Ireland is following international trends as endothelial procedures have become the most common approach since 2018. However, a low overall number of transplants is performed in Ireland compared with other countries suggesting that care pathways should be implemented to improve access to corneal transplantation.

Preparation of endothelial keratoplasty lenticules with Gebauer SLc Original versus Moria CBm Carriazo-Barraquer and Moria One-Use Plus microkeratomes

Purpose

To investigate endothelial keratoplasty lenticules prepared from fresh whole eyes via Gebauer SLc Original (SLc) versus Moria CBm Carriazo-Barraquer (CBm), and those prepared from corneoscleral buttons via SLc versus Moria One-Use Plus (OUP) in terms of eye bank preparation criteria.

Methods

Fresh whole eyes-dissected endothelial keratoplasty lenticules with SLc were compared with CBm in terms of thickness profile measurements, over/under dissection values, endothelial cell loss, and postoperative graft failures. A similar comparison was made between corneoscleral buttons-dissected endothelial keratoplasty lenticules with SLc and OUP.

Results

Means of central thicknesses and increase of thickness toward periphery were not significantly different between 33 fresh whole eyes-dissected endothelial keratoplasty lenticules with SLc and 33 fresh whole eyes-dissected ones with CBm. There was no significant difference between 19 corneoscleral buttons-dissected endothelial keratoplasty lenticules with SLc and 19 corneoscleral buttons-dissected ones with OUP in terms of mean central thickness and post-cut endothelial cell loss. However, in the corneoscleral buttons-dissected endothelial keratoplasty lenticules, a mean increase of thickness was significantly different from central to two pericentral locations with OUP (P = 0.001) and from central to two peripheral parts with SLc (P = 0.011). Both CBm and OUP systems showed deeper dissection depths than head descriptions as compared to SLc (P < 0.001).

Conclusion

Unlike fresh whole eyes-dissected endothelial keratoplasty lenticules with SLc or CBm, thickness profiles of corneoscleral buttons-dissected endothelial keratoplasty lenticules with both SLc and OUP systems showed a partial asymmetric increase of thickness toward the periphery. A high agreement was observed between endothelial keratoplasty lenticules thicknesses and SLc nomograms.

A 27-Year Report from the Central Eye Bank of Iran

Purpose

To report the 27-year statistical data from the Central Eye Bank of Iran (CEBI) and its activity.

Methods

All CEBI records regarding procured eyes, tissue utilizations, corneal transplants per capita, and indications for keratoplasty from 1991 to 2017 were analyzed.

Results

In total, 115,743 whole eyes were donated during the 27-year period. Out of the 114,169 eyes donated between 1994 and 2017, 95,314 eyes were distributed for transplantation, and 95,057 corneas were actually transplanted. The mean annual rate of corneal transplants per capita was 55.10 - 6 ± 27.10 - 6 . Although penetrating keratoplasty (PKP, 70%) was the most common technique of corneal transplantation during the study period, it exhibited a decreasing trend between 2006 and 2017 (P = 0.048). It was in contrast to Descemet stripping automated endothelial keratoplasty (DSAEK) that demonstrated an increasing trend during the same period (P < 0.001). Keratoconus (KCN, 39.70%) was the most leading indication for keratoplasty over the last three decades followed by bullous keratopathy (BK, 18.5%), corneal scar and opacities (15.7%), and graft failure (GF, 7.5%), with an increasing trend for BK, GF, and KCN. A majority of scleral tissues (83.7%) were utilized for orbital implant protection.

Conclusion

An increasing trend in the number of procured eyes was observed over the past 27 years in Iran. The most leading indications for corneal transplantation were KCN and BK. While PKP was the most common keratoplasty technique, DSAEK showed an increasing trend over the last 12 years.

Changing Trends in Penetrating Keratoplasty Indications between 2011 and 2018 - Histopathology of 2123 Corneal Buttons in a Single Center in Germany

Purpose: To analyse the changing trends in penetrating keratoplasty indications between January 2011 and December 2018, at the Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar, Germany. Patients and Methods: This is a retrospective review of 2123 corneal buttons of 1776 patients (1993 eyes, 56.0% males, age at the time of surgery 57.6 ± 18.7 years), who underwent penetrating keratoplasty (PKP) between January 2011 and December 2018. The classification was performed based on histological analysis and using the priority scheme of Brady et al., supplemented by a group of "failed endothelial keratoplasty grafts". Our groups were the following: pseudophakic or aphakic bullous keratopathy, regraft, failed endothelial keratoplasty graft, acute necrotizing and ulcerative keratitis, keratoconus, Fuchs' dystrophy, corneal dystrophy other than Fuchs', corneal scars and other diagnoses. Results: Between 2011 and 2018, keratoconus was the leading indication for PKP in 455 (21.5%) cases, followed by acute necrotizing and ulcerative keratitis in 384 (18.1%), regraft in 367 (17.3%), corneal scars in 350 (16.5%), pseudophakic or aphakic bullous keratopathy in 225 (10.6%), Fuchs' dystrophy in 194 (9.1%), other diagnoses in 64 (3.0%), corneal dystrophy other than Fuchs' in 52 (2.4%), and failed endothelial keratoplasty graft in 32 (1.5%) cases. Conclusions: With the introduction of posterior lamellar keratoplasty, keratoconus remains the leading PKP indication in our center with excimer laser-trephination on a routine basis. A trend towards increasing numbers can be observed regarding acute necrotizing and ulcerative keratitis patients and regrafts. However, the incidence of Fuchs' dystrophy decreased dramatically within PKP patients, with the introduction of posterior lamellar keratoplasty.

Proposed risk factors for failure of transplanted eye bank-prepared descemet stripping automated endothelial keratoplasty tissues

To investigate the possible risk factors for failure of transplanted eye bank-prepared Descemet stripping automated endothelial keratoplasty (DSAEK) tissues. In a retrospective study between March 2011 and March 2019, all the failed DSAEK cases (131 cases) reported to the Central Eye Bank of Iran were compared with a surgeon-matched successful DSAEK group (control, 126 cases) in terms of the donor, DSAEK tissue, and recipient characteristics. Univariate analysis indicated that the DSAEK tissue preparation from excised corneoscleral tissues (OR 2.17; P = 0.026) and donor conjunctival hyperemia (OR 1.62; P = 0.042) were more common in the re-DSAEK group than in the controls. Other donor and recipient characteristics as well as other DSAEK tissue criteria were not significantly different between the re-DSAEK and control groups. DSAEK lenticules in both re-DSAEK and control groups demonstrated symmetric contours. Subgroup analyses in the re-DSAEK group revealed a higher rate of surgeons' low to moderate experience in comparison to those of high experience (P < 0.001). Additionally, failed DSAEK was observed more commonly in donors aged over 50 years than among those under 30 years (P < 0.001). Our study showed that DSAEK tissues prepared from excised corneoscleral tissues and from donors with conjunctival hyperemia were associated with higher rates of re-DSAEK due to failed DSAEK. An increasing trend of re-DSAEK was observed with shorter surgeons' experience and more advanced donor's age.

Indications for penetrating keratoplasty and anterior lamellar keratoplasty during 2010-2017

AIM

To review the indications of penetrating keratoplasty (PK) and anterior lamellar keratoplasty (ALK) at Qingdao Eye Hospital, Shandong Eye Institute, Qingdao, China, from 2010 to 2017.

METHODS

The data of all patients undergoing PK or ALK from January 2010 to December 2017 was retrospectively reviewed, with the indications during 2010-2013 and 2014-2017 compared.

RESULTS

A total of 1869 eyes were included, among which 1405 eyes (75.2%) had PK and 464 eyes (24.8%) had ALK. The leading indications were suppurative keratitis (36.8%), keratoconus (15.5%), herpes keratitis (13.1%), and regraft (10.5%). In eyes undergoing PK, the top four indications were suppurative keratitis (38.7%), herpes keratitis (15.3%), keratoconus (12.6%), and regraft (12.5%) during 2014-2017, with the proportion of suppurative keratitis and herpes keratitis decreased while regraft and keratoconus increased compared with 2010-2013. In eyes with ALK, suppurative keratitis (30.8%), keratoconus (24.1%), corneal dystrophies and degenerations (10.6%), and corneal dermoid tumor (9.7%) were the top four indications, and there was no significant difference for the proportion of each indication between 2010-2013 and 2014-2017.

CONCLUSION

Suppurative keratitis is the most common indication for PK and ALK at Qingdao Eye Hospital during 2010-2017, followed by keratoconus, herpes keratitis, and regraft. In eyes treated with PK, the proportion of suppurative keratitis and herpes keratitis decrease while regraft and keratoconus increase during 2014-2017 compared with 2010-2013.

Fuchs endothelial corneal dystrophy and corneal endothelial diseases: East meets West

Fuchs endothelial corneal dystrophy (FECD) is amongst one of the most common indications for endothelial keratoplasty worldwide. Despite being originally described among Caucasians, it is now known to be prevalent among a large number of populations, including Asians. While the FECD phenotype is classically described as that of central guttate and pigment deposits associated with corneal endothelial dysfunction, there are subtle yet important differences in how FECD and its phenocopies may present in Caucasians vs Asians. Such differences are paralled by genotypic variations and disease management preferences which appear to be geographically and ethnically delineated. This article provides a succinct review of such differences, with a focus on diagnostic and management issues which may be encountered by ophthalmologists practicing in the different geographic regions, when evaluating a patient with FECD.

Topical Rho-Associated Kinase Inhibitor, Y27632, Accelerates Corneal Endothelial Regeneration in a Canine Cryoinjury Model

PURPOSE

Corneal endothelial cell regeneration varies by species, with nonhuman primates (NHPs) and rabbits displaying low and high proliferative capacities, respectively. Recent studies report that topical application of rho-associated kinase (ROCK) inhibitors accelerates corneal endothelial wound healing in animal models and human patients with endothelial dysfunction. This study determines the regenerative capacity of canine corneal endothelial cells in vivo and their response to a topical ROCK inhibitor, Y27632, after transcorneal freezing.

METHODS

Right eyes of 6 beagles underwent transcorneal freezing; 10 mM ROCK inhibitor Y27632 or vehicle control was applied topically to both eyes at least 4 times daily for 56 days. Endothelial cell density was evaluated by in vivo confocal microscopy, and corneal thickness was measured by Fourier-domain optical coherence tomography (FD-OCT) and ultrasound pachymetry.

RESULTS

Transcorneal freezing induced severe central corneal edema in dogs, with restoration of transparency occurring within 4 weeks. Y27632 significantly decreased corneal thickness by FD-OCT and ultrasound pachymetry in the acute phase and significantly increased endothelial cell density at days 28 and 42 post-cryoinjury, suggesting faster restoration of endothelial cell recovery.

CONCLUSIONS

Canine corneal endothelial function recovers at a similar rate as NHPs but more slowly than rabbits after cryoinjury. Faster corneal endothelial wound healing was observed by in vivo confocal microscopy and FD-OCT in dogs treated with Y27632 versus vehicle controls. Thus, a canine cryoinjury model may be a useful alternative to NHPs in detecting a response to therapies directed at endothelial regeneration.

Public attitudes toward corneal donation in northern Jordan

Purpose

The aims of this study were to assess the knowledge and attitude toward corneal donation among Jordanian population and to report the reasons which may influence subject’s decision and attitude toward corneal donation.

Methods

A self-designed questionnaire was developed. The participants were asked about reasons for both willingness and unwillingness to donate their corneas. These reasons were stated in the questionnaire and the participants had to express their agreement by one of five options: strongly disagree, disagree, neutral, agree, or strongly agree.

Results

A total of 500 participants (218 males and 282 females) completed the questionnaire. The average age (±SD) of the study participants was 32.8 (±11.7) years. About 67.2% of the subjects were willing to donate their corneas, whereas 32.8% were not willing to do so. The main motive for willingness was doing a good deed by helping others to see. On the other hand, fear of the body being treated badly and that other organ might be taken than the ones specified for donation were the main reasons for unwillingness to donate corneas. The age of participants, gender, and the monthly income did not significantly influence the willingness to donate (P>0.05). However, the level of education had a significant influence on people’s decision to donate their corneas.

Conclusion

Many Jordanians have positive attitude toward corneal donations. Ethical factors need to be addressed to promote for corneal donation. In addition, increasing the awareness of donation and its benefits may help increase the supply of corneal tissues.

Descemet's membrane endothelial keratoplasty (DMEK) versus Descemet's stripping automated endothelial keratoplasty (DSAEK) for corneal endothelial failure

BACKGROUND

Corneal endothelial transplantation has become the gold standard for the treatment of corneal endothelial dysfunctions, replacing full thickness transplantation, known as penetrating keratoplasty. Corneal endothelial transplantation has been described using two different techniques: Descemet's membrane endothelial keratoplasty (DMEK) and Descemet's stripping automated endothelial keratoplasty (DSAEK). Both are still performed worldwide.

OBJECTIVES

To compare the effectiveness and safety of Descemet's membrane endothelial keratoplasty (DMEK) versus Descemet's stripping automated endothelial keratoplasty (DSAEK) for the treatment of corneal endothelial failure in people with Fuch's endothelial dystropy (FED) and pseudophakic bullous keratopathy (PBK).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 7); MEDLINE Ovid; Embase Ovid; LILACS BIREME; the ISRCTN registry; ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). The date of the search was 11 August 2017.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and non-randomised paired, contralateral-eye studies in any setting where DMEK was compared with DSAEK to treat people with corneal endothelial failure.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, assessed trial quality and extracted data using the standard methodological procedures expected by Cochrane. Our primary outcome was best corrected visual acuity (BCVA) measured in logarithm of the Minimum Angle of Resolution (logMAR). Secondary outcomes were endothelial cell count, graft rejection, primary graft failure and graft dislocation. We graded the risk of bias of non-randomised studies (NRSs) using ROBINS-I.

MAIN RESULTS

We did not identify any RCTs but found four non-randomised studies (NRSs) including 72 participants (144 eyes), who had received DSAEK in the first eye followed by DMEK in the fellow eye. All the studies included adult participants where there was evidence of FED and endothelial failure requiring a corneal transplant for the treatment of visual impairment. We did not find any studies that included PBK. The trials were published between 2011 and 2015, and we assessed them as high risk of bias due to potential unknown confounding factors since DSAEK preceded DMEK in all participants. Two studies reported results at 12 months, one at 6 months, and one between 6 and 24 months. At one year, using DMEK in cases of endothelial failure may result in better BCVA compared with DSAEK (mean difference (MD) -0.14, 95% confidence interval (CI) -0.18 to -0.10 logMAR, 4 studies, 140 eyes, low-certainty evidence). None of the participants had severe visual loss (BCVA of 1.0 logMAR or more; very low-certainty evidence). Regarding endothelial cell count data (4 studies, 134 eyes) it is hard to draw any conclusions since two studies suggested no difference and the other two reported that DMEK provides a higher cell density at one year (very low-certainty evidence). No primary graft failure and only one graft rejection were recorded over four studies (144 eyes) (very low-certainty evidence). The most common complications reported were graft dislocations, which were recorded in one or two out of 100 participants with DSAEK but were more common using DMEK, although this difference could not be precisely estimated (risk ratio (RR) 5.40, 95% CI 1.51 to 19.3; 4 studies, 144 eyes, very low-certainty evidence).

AUTHORS' CONCLUSIONS

This review included studies conducted on people with corneal endothelium failure due to FED for whom both DMEK and DSAEK can be considered, and found low-certainty evidence that DMEK provides some advantage in terms of final BCVA, at the cost of more graft dislocations needing 're-bubbling' (very low-certainty of evidence).

New trends in corneal transplants at the University of Toronto

OBJECTIVE

To assess trends in surgical procedures and indications for all corneal transplants performed at the University of Toronto.

DESIGN

Retrospective cross-sectional study.

PARTICIPANTS

One thousand one hundred and four consecutive corneal transplants performed at the Kensington Eye Institute (KEI).

METHODS

Demographic, clinical, and pathological data retrieved from the Ophthalmic Pathology Laboratory on all corneal transplants performed at the KEI from January 2014 to December 2016.

RESULTS

Over 3 years, partial-thickness lamellar keratoplasties were performed in 880 cases (80%) while full-thickness penetrating keratoplasties (PKP) accounted for 224 cases (20%). Leading causes of corneal transplant were Fuchs' dystrophy (42%), graft failure (17%), bullous keratopathy (15%), and keratoconus (15%). Graft failure (40%) and keratoconus (31%) were the leading causes for PKP. Descemet's membrane endothelial keratoplasty (DMEK) accounted for 37% of cases, Descemet's stripping automated endothelial keratoplasty (DSAEK) for 30%, and deep anterior lamellar keratoplasty (DALK) for 13%. By 2016, partial-thickness procedures had increased by 10%, accounting for 85% of all procedures. In addition, DMEK increased by 26%, DSAEK decreased by 13%, and PKP decreased by 11%. Fuchs' dystrophy remained the leading indication for DMEK (67%) and DSAEK (42%) procedures. In 2016, 73% of DALK procedures were for the treatment of keratoconus.

CONCLUSIONS

Partial-thickness corneal transplants now account for 85% of all current graft procedures, and DMEK has emerged as the procedure of choice. Graft failure continues to be the leading indication for full-thickness grafts. Longitudinal studies are needed to determine whether these new trends persist and their future impact on graft failures.

Corneal transplantation trends in France from 2004 to 2015: A 12-year review

Purpose:

The aim of this study was to report the 12-year longitudinal trends in indication and corneal transplantation techniques in France from 2004 to 2015.

Results:

The records of all corneal transplantations performed from 2004 to 2015 in France were retrospectively reviewed. The patient indications and types of transplant performed were analyzed. A total of 46,658 corneal transplantations were performed between 2004 and 2015, with 34,187 (73.3%) penetrating keratoplasty and 10,452 (22.4%) lamellar keratoplasty. The leading surgical indications were secondary endothelial failure (24.3%), keratoconus (18.8%), regraft (13.5%), and Fuchs endothelial corneal dystrophy (15.1%). Endothelial keratoplasty became the preferred technique for endothelial diseases and deep anterior lamellar keratoplasty the preferred technique for keratoconus, surpassing penetrating keratoplasty in 2013.

Conclusion:

Secondary endothelial failure is the top indication for performing a keratoplasty over the 12-year period. There was a shift from penetrating keratoplasty to endothelial keratoplasty performed for Fuchs endothelial corneal dystrophy and secondary endothelial failure, and to deep anterior lamellar keratoplasty, performed for keratoconus. This highlights an important shift in managing corneal diseases toward the application of selective and more conservative surgeries and changes in indications in corneal transplantation.

Analysis of penetrating keratoplasty in Northern Alberta, Canada, from 2000 to 2015

OBJECTIVE

To study indications for penetrating keratoplasty (PK) at a single site. The trends in the causative organisms for infectious keratitis requiring surgery were also evaluated.

DESIGN

Retrospective observational study.

PARTICIPANTS

A total of 1181 eyes of 935 patients undergoing PK between January 2000 and December 2015 in Northern Alberta, Canada.

METHODS

Indications for PK were evaluated over the 16-year study period, and the trends in these indications were compared over 5-year intervals. The microbiology of infectious keratitis cases requiring surgery was similarly evaluated.

RESULTS

The most common indications for PK from 2000 to 2015 were keratoconus (23%), re-graft (22%), and corneal scar (12%). There was a decline in the percent of total surgeries done for Fuchs' dystrophy (p = 1.1 × 10^-3) and pseudophakic bullous keratopathy (p = 5.6 × 10^-5), whereas a corresponding increase in keratoconus (p = 3.2 × 10^-5), trauma (p = 2.1 × 10^-3), and infectious keratitis cases (p = 0.010) was observed. The most common causes for infectious keratitis cases were viral (45%), bacterial (18%), parasitic (11%), and fungal (9%). There was a significant increase in the percent of infectious keratitis cases due to a viral etiology from 2005 to 2010 (p = 6.4 × 10^-3).

CONCLUSIONS

The indications for PK are comparable with other centres in North America. Nearly half of all infectious keratitis cases requiring surgery are viral. The increase in viral cases requiring surgery may reflect improved diagnostics or recurrent cases.

[Riboflavin UVA crosslinking in progressive keratoconus]

In patients with keratoconus, a progressive, ectatic disease of the cornea, the shape of the cornea is continuously changing leading to a reduction in visual acuity by progressive myopia and more and more (irregular) astigmatism. The symptomatic treatment consists of the prescription of glasses or special gas-permeable rigid contact lenses. Corneal tomography is generally used for diagnosis. After initial diagnosis of keratoconus, regular tomographic follow-ups should be performed. If clinically significant progression is found and confirmed by repeated measurements, riboflavin UVA collagen crosslinking should be offered to the patients. The aim of riboflavin UVA collagen crosslinking is to halt the progression of the disease to avoid further complications. The therapeutic principle is a combined effect of the photosensitizer riboflavin and UVA light. This stiffening effect of the corneal tissue halts the progression of keratoconus. The efficacy of this treatment has been demonstrated in various randomized, controlled trials.

An 11-Year Review of Keratoplasty in a Tertiary Referral Center in Turkey: Changing Surgical Techniques for Similar Indications

OBJECTIVES

Study aims to evaluate the indications and surgical techniques for corneal transplantation and to report changes in trends for preferred keratoplasty surgical techniques.

METHODS

Clinical records of 815 consecutive corneal transplantations between January 1, 2004 and December 31, 2014 in Haydarpasa Numune Training and Research Hospital Eye Clinic were analyzed and classified into seven broad groups according to indications. Main outcome measures were change of leading indications and trends for surgical techniques.

RESULTS

Leading indications for keratoplasty were keratoconus (KCN) (27.7%), bullous keratopathy (BK) (23%), postinfectious corneal scars (13.5%), regrafts (13.1%), corneal dystrophies (12.1%), and noninfectious corneal scars (5.4%). Regrafts were the only indication with a significantly increasing trend (P<0.01). Since the introduction of lamellar keratoplasty (LK) techniques including deep anterior lamellar keratoplasty (DALK) and Descemet stripping automated endothelial keratoplasty (DSAEK), there was a significant increasing trend in number and percentage of both LK techniques (DALK; P=0.001 and P=0.007, and DSAEK; P<0.001 and P<0.001, respectively) and a significant corresponding decline in the percentage of penetrating keratoplasty (PK) (P<0.01). Similarly, DALK and DSAEK replaced PK as the preferred surgical technique for KCN and BK indications, (P=0.007 and P=0.01, respectively). Although PK was the most common surgical technique over the 11-year period (54.7%), both anterior and posterior LK techniques showed an emerging trend as the procedures of choice when indicated.

CONCLUSIONS

No major shift was observed in the clinical indications for corneal transplantation over the previous 11 years, except for regrafts. Lamellar keratoplasty techniques largely overtook the PK technique, but PK was still the overall preferred technique in the era when both LK techniques were used.

Tuck-in Lamellar keratoplasty with an lenticule obtained by small incision lenticule extraction for treatment of Post- LASIK Ectasia

Corneal ectasia is a rare but serious post-operative complication of LASIK. Our main aim was to describe and evaluate the efficacy and safety of tuck-in lamellar keratoplasty with an lenticule obtained by SMILE for treatment of Post LASIK Ectasia. Tuck-in lamellar keratoplasty was performed on three post-LASIK cornea ectasia patients (three eyes) with central corneal thickness less than 400 µm. Each patient was monitored for at least 12 months. Our primary outcomes measured pre and post-operatively included: Anterior segment optical coherence tomography(AS-OCT), corneal topography and monitored by slit-lamp microscopy. The mean total corneal thickness preoperatively and 1 day, 1 month, 3 months and 12 months post-op were 360.00 ± 32.07 µm, 590.00 ± 10.00 µm, 536.67 ± 11.54 µm, 523.33 ± 37.85 µm, 466.67 ± 41.63 µm. The mean lenticule implanted 1 day, 1 month, 3 months and 12 months post-op were 173.33 ± 41.63 µm,136.67 ± 25.16 µm, 133.33 ± 40.41 µm, 130.00 ± 17.32 µm. There was no evidence of immune rejection or other complications. Tuck-in lamellar keratoplasty with an lenticule obtained by SMILE seems to be a safe and alternative surgical approach in the treatment of post - LASIK cornea ectasia, especially for severe cases with cornea thickness less than 400 μm.

Trends in Corneal Transplantation in Keratoconus

PURPOSE

To determine recent trends in and sociodemographic/comorbid conditions associated with penetrating keratoplasty (PK) and lamellar keratoplasty (LK) for keratoconus (KCN).

METHODS

Patients with KCN and subsequent PK and LK procedures were identified using International Classification of Diseases, 9th revision (ICD-9) and Current Procedural Terminology (CPT) billing codes. The change in surgical rates was calculated over a decade, and multivariate analysis demonstrated factors associated with undergoing surgery.

RESULTS

A total of 21,588 patients with KCN underwent 1306 PK procedures and 109 LK procedures during the study period. Individuals were significantly less likely to undergo PK from 2009 to 2012 compared with 2001 to 2008 [odds ratio (OR) 0.57, 95% confidence interval (CI) 0.47-0.68, P < 0.001]. Multivariate analysis revealed the factors that increased the likelihood of PK alone and included age 20 to 40 (OR 1.90, 95% CI, 1.19-3.04, P < 0.001), black race (OR 1.36, 95% CI, 1.06-1.74, P = 0.01), and education less than a bachelor's degree or only a high school diploma (OR 1.94-2.84, P < 0.001 for all comparisons). Female sex (OR 0.74, 95% CI, 0.63-0.88, P < 0.001) and household net worth either between 150 and 249k (OR 0.64, 95% CI, 0.48-0.84, P < 0.001) or more than $500,000 (OR 0.71, 95% CI, 0.51-0.99, P = 0.03) were traits associated with decreased odds of PK. No significant associations for LK were observed.

CONCLUSIONS

The rate of PK in KCN is decreasing in the United States. The third or fourth decade of life, male sex, black race, lower education, and greater household net worth are associated with increased odds of PK.

Clinical and epidemiological aspects of cornea transplant patients of a reference hospital

Objective:

clinically characterizing cornea transplant patients and their distribution according to indicated and post-operative conditions of cornea transplantation, as well as estimating the average waiting time.

Method:

a cross-sectional, descriptive and analytical study performed for all cornea transplants performed at a reference service (n=258). Data were analyzed using Statistical Package for the Social Sciences, version 20.0.

Results:

the main indicator for cornea transplant was keratoconus. The mean waiting time for the transplant was approximately 5 months and 3 weeks for elective transplants and 9 days for urgent cases. An association between the type of corneal disorder with gender, age, previous surgery, eye classification, glaucoma and anterior graft failure were found.

Conclusion:

keratoconus was the main indicator for cornea transplant. Factors such as age, previous corneal graft failure (retransplantation), glaucoma, cases of surgeries prior to cornea transplant (especially cataract surgery) may be related to the onset corneal endothelium disorders.

Changes in Technique and Indications for Keratoplasty in Poland, 1989 to 2014: An Analysis of Corneal Transplantations Performed at Saint Barbara Hospital, Trauma Center, Sosnowiec, Poland

BACKGROUND

The purpose of this work was to study the evolving trends in techniques and indications for corneal transplantation in Poland.

METHODS

This retrospective, descriptive analysis of corneal transplantations was performed at the Ophthalmology Department of Saint Barbara Hospital, Trauma Center, Sosnowiec, Poland, between 1988 and 2014. Structure of indications and surgery type rates over 26 years were tabulated by means of 5-year intervals.

RESULTS

Between 1989 and 2014, 1762 corneal transplantations were performed, including 1375 (78%) cases of penetrating keratoplasty, 137 (8%) lamellar keratoplasty, 112 (6%) patch grafts, and 138 (8%) keratolimbal allografts. The major indications and their respective overall percentage were corneal leucoma (24%), pseudophakic/aphakic bullous keratopathy (22%), Fuchs dystrophy (13%), keratoconus (13%), re-graft (11%), keratitis (9%), and limbal stem cell deficiency (8%), with changes in relative frequency of the leading indications over the following time intervals. The number of corneal transplantations gradually increased during the years reviewed. The rates of lamellar, keratolimbal, and patch grafts have grown dynamically since 2010, reaching 20%, 17%, and 12%, respectively, of procedures performed during 2010 to 2014.

CONCLUSIONS

Over the past quarter of a century, there has been evolution in corneal transplantation service, from the first penetrating keratoplasty to the wide spectrum of procedures, including femtosecond laser-assisted keratoplasty. Although, since 2010, the rates of lamellar and keratolimbal allografts have grown rapidly, penetrating keratoplasty has remained the leading technique.

Refractive outcomes of penetrating keratoplasty and deep anterior lamellar keratoplasty in fellow eyes for keratoconus

PURPOSE

To compare the refractive outcomes following penetrating keratoplasty and deep anterior lamellar keratoplasty in fellow eyes in patients with keratoconus.

METHODS

This is an observational retrospective review of consecutive patients with keratoconus first managed with penetrating keratoplasty in one eye and then with lamellar keratoplasty in the fellow eye, between 2002 and 2007. Data collection was based on patients' hospital records. Information related to assessment before surgery and at 1, 3, 6, 12, 24, and 48 months after keratoplasty were retrieved and considered in the analysis. Clinical evaluations included patients' medical histories and diagnosis of keratoconus, uncorrected and best corrected visual acuity, spherical equivalent, refractive cylinder, topographic cylinder, and high-order aberrations, complications, and adverse reactions. Data on contrast sensitivity, central corneal thickness, and central residual bed thickness (only for lamellar keratoplasty) were retrieved from anterior segment optical coherence tomography observation performed at 48 months.

RESULTS

Sixteen patients (32 eyes), 7 males and 9 females, were included in the analyses. After 4 years from transplantation, at the end of follow-up, no statistically significant differences were found in visual acuity and refractive measures between the two keratoplasties. Perforating keratoplasty showed significant differences for contrast sensitivity at 6 cpd with maximum glare (p = 0.026) and without glare (p = 0.015). Deep anterior lamellar keratoplasty showed a negative correlation between central residual bed thickness and best corrected visual acuity (R = -0.414, p < 0.001).

CONCLUSIONS

The manual pre-descemetic deep anterior lamellar keratoplasty used in this study showed refractive and visual results comparable to those obtained with penetrating keratoplasty. Such results indicated that leaving healthy stroma attached to Descemet's membrane does not compromise the clinical outcome in the short and long term after surgery.