Indications and techniques employed for keratoplasty in the Eastern province of Saudi Arabia: 6 years of experience

Awareness of Keratoconus and Its Relationship With Eye Rubbing Among the Population of the Eastern Province of Saudi Arabia

BACKGROUND

Keratoconus is an eye condition where the cornea, the clear, dome-shaped front part of the eye, becomes thinner and gradually bulges outward into a cone shape. Keratoconus usually affects both eyes. The exact cause of keratoconus is unknown, but it is believed to involve a combination of genetic and environmental factors.

AIM

This study aims to assess the awareness level of keratoconus and its relation to eye rubbing among the population in the Eastern Province of Saudi Arabia.

METHODS

A cross-sectional study was conducted in the Eastern Province of Saudi Arabia, involving all eligible participants via an online pre-designed questionnaire from March to June 2023. The data were collected through social media.

RESULTS

A total of 388 eligible participants completed the study questionnaire. Participants' ages ranged from 19 to 60 years, with a mean age of 26.2 ± 13.9 years. There were 265 (68.3%) female participants. Regarding public awareness about keratoconus among participants in the Eastern Province of Saudi Arabia, our research revealed a total of 101 (26%) participants had an overall good awareness of keratoconus, while 287 (74%) had a poor awareness level. The most reported source of information included scientific lectures (21.6%). Precisely, 316 (81.4%) of the research subjects rub their eyes primarily because of allergies (7%), strain headaches (25%), and itching (66.5%).

CONCLUSION

Most of the study participants have poor awareness about keratoconus and its relation to eye rubbing. Health education programs for the population should be conducted to enhance public awareness about keratoconus.

Penetrating Keratoplasty: Indications and Graft Survival by Geographic Region

Corneal transplantation, or penetrating keratoplasty (PK), is the most common form of solid-organ transplantation performed worldwide. Here, we evaluated the indications for PK and rates of transplant survival around the world by geographic region. We conducted a literature search of PubMed, MEDLINE, and Google Scholar databases and identified 155 relevant studies from 41 countries published between 1987 and 2021. The most common indications for PK were keratoconus in Europe, Africa, the Middle East, Australia, New Zealand, and Central and South America, bullous keratopathy in North America, and corneal scarring in Asia. The overall global mean graft survival rates at 1-, 2-, 3-, 5-, and 10-years were 88.6%, 81.2%, 78.9%, 72.8%, and 61.2%, respectively. Through this systematic analysis of PK by region, we hope to bring a new perspective to the corneal transplantation literature and to potentially highlight global differences and unmet needs in patient care.

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.

Surgeons preferences in descemet membrane endothelial keratoplasty (DMEK)

AIM

To explore the attitudes, preferences, and barriers of DMEK among corneal specialists in Saudi Arabia.

METHOD

An anonymous survey was sent through an online platform to members of the Saudi Ophthalmological Society. The survey was designed to capture data covering: demographic data, practice patterns of keratoplasty techniques, DMEK technique preferences, barriers, and facilitators to performing DMEK.

RESULTS

Thirty-five (33% response rate) surgeons participated in the questionnaire. Sixty-eight percent were in practice for less than or equal to 10 years. Thirteen surgeons were performing DMEK. Participating in any training capacity was observed among surgeons who performed DMEK (92%). The main selection criteria for this procedure were patients with normal anterior chamber anatomy (77%). The main barrier against DMEK adoption among surgeons who do not perform the procedure was the lack of experience (91%). Strategies to help begin performing DMEK were eye banks support (prepared grafts, backup tissue for inadvertent loss), access to wet-lab training courses, and higher surgical volume.

CONCLUSION

DMEK is not highly performed among corneal specialists in Saudi Arabia; however, there is evident interest in adopting this technique. Strategies toward filling the gap of lacking experience would facilitate the adoption of the procedure. Eye banks play a crucial role by providing prepared tissues, which would lessen part of the technical difficulty.

Outcomes of Descemet Membrane Endothelial Keratoplasty in Bangkok, Thailand

Purpose

To investigate the medium-term clinical outcomes and risk factors for primary graft failure after Descemet membrane endothelial keratoplasty (DMEK) in Thai patients.

Patients and Methods

This is a single-center retrospective cohort study. Sixty-two eyes of 62 patients who underwent DMEK at Ramathibodi Hospital, Bangkok, Thailand, with a minimum of 24-month follow-up were recruited. Preoperative donor and recipient characteristics, intraoperative data, and postoperative outcomes including best-corrected visual acuity (BCVA), graft clarity, endothelial cell density (ECD), central corneal thickness (CCT), and complications were evaluated at 1, 3, 6, 12, and 24 months after surgery.

Results

The mean age of the patients was 67.2 ± 9.9 years, and 52% were female. The mean follow-up time was 37.5 ± 11.0 months. The most common indications for DMEK were Fuchs' endothelial corneal dystrophy (FECD) (53.2%) and pseudophakic bullous keratopathy (PBK) (17.7%). Nearly half of patients had triple-DMEK. The median preoperative BCVA was 20/400. Postoperative BCVA of ≥ 20/40 was reached in 37.1% and of ≥ 20/20 in 6.5% after 1 month which increased to 54.8% and 17.7% after 3 months; and to 67.7% and 27.4% after 24 months. Endothelial cell loss (ECL) at 3, 6, 12, and 24 months was 30.5%, 33.8%, 44.4%, and 45.9%, respectively. Graft diameter was the single factor, showing a significant relationship with postoperative ECD. Most frequent postoperative complications included graft detachment (22.6%), increased IOP/glaucoma (17.7%), and primary graft failure (16.1%). In univariate analysis, death-to-operation time and the diagnosis of PBK were significantly associated with the occurrence of primary graft failure.

Conclusion

DMEK is a safe, effective, and feasible treatment for endothelial failure in Asian eyes. Careful case selection, use of relatively fresh donor tissues, and appropriate surgical techniques can prevent primary graft failure and facilitate optimal outcomes following surgery.

Changing Indications for Penetrating Keratoplasty in Bahrain in a Tertiary Referral Centre

PURPOSE

To study the changing indications for Penetrating keratoplasty in Bahrain and to compare them with published data.

PATIENTS AND METHODS

A Retrospective review of available records of patients who underwent penetrating keratoplasty at a tertiary center in Bahrain (1996-2015). The trend of each indication was analyzed. The study was subdivided into three periods for correlation purposes. Pearson Coefficient r and the p values were used for interpretation of data. The results were compared with similar studies.

RESULTS

A total of 298 patients underwent keratoplasty in the study period, which is from 1996 until 2015 (missing data 2009-2011). Keratoconus was found to be the leading indication, accounting for 33% of the total cases, followed by trachoma 27%, followed by aphakic and pseudophakic bullous keratopathies 13%. Trachoma showed a statistically significant decreasing trend (p < 0.001), Keratoconus had an increasing trend (p<0.001). Bullous keratopathy showed an increasing trend (p = 0.001) with an abrupt rise after 2012.

CONCLUSION

Corneal scarring due to old trachoma was the leading indication for keratoplasty 20 years ago in Bahrain. However, due to improvement of health awareness, hygiene, and the socioeconomic status, this has regressed with keratoconus becoming the leading indication from 2002 onwards. A surge of bullous keratopathy was noted after 2012, placing it as the second commonest indication. This may be due to the introduction of phacoemulsification technique for cataract surgery, and perhaps because the nature of the institute being a teaching hospital. Keratoconus is the leading indication and showed an increasing trend. It is recommended to perform a keratoconus screening program for early detection and prevention.

Indications, surgical procedures and outcomes of keratoplasty at a Tertiary University-based hospital: a review of 10 years' experience

OBJECTIVE

To investigate keratoplasty outcomes in a university-based hospital.

METHODS

Medical records of all patients undergoing keratoplasty at King Abdulaziz University Hospital, Riyadh, Saudi Arabia, between January 1, 2006, and December 31, 2015, with a minimum follow-up period of three months were reviewed retrospectively. Indications, surgical procedures, complications and outcomes of all surgeries were collected and analyzed.

MAIN OUTCOME MEASURES

Graft survival and visual acuity.

RESULTS

Data were available for 488 grafts in the study period, including 313 optical penetrating keratoplasty (PKP), 42 therapeutic/tectonic PKPs, 72 deep anterior lamellar keratoplasty, 58 Descemet's stripping automated endothelial keratoplasty and 3 Descemet's membrane endothelial keratoplasty. A total of 389 (79.7%) grafts survived, whereas 99 (20.3%) grafts failed. The projected 1-year, 3-year and 5-year cumulative survival rates for the entire study group were 85.8%, 74.9% and 71.1%, respectively. Corneal ectasia was the commonest surgical indication accounting for 48% of the cases. The best long-term survival rates were observed in the stromal dystrophy and corneal ectasia groups. The worst survival rates were noticed in the congenital corneal opacities group. Vision improved in in 57.5% of grafted eyes, remained the same in 39.8% and deteriorated in 2.7%. Postoperative complications occurred in 36% of the grafts with rejection being the most common, and its mere occurrence increased the risk of graft failure by 20-fold.

CONCLUSION

The outcome of grafting in a university-based hospital can be excellent in low-risk grafts and fair to low in high-risk grafts. Our results are relatively comparable to nationally and internationally reported outcomes.

Corneal dystrophies

Corneal dystrophies are broadly defined as inherited disorders that affect any layer of the cornea and are usually progressive, bilateral conditions that do not have systemic effects. The 2015 International Classification of Corneal Dystrophies classifies corneal dystrophies into four classes: epithelial and subepithelial dystrophies, epithelial-stromal TGFBI dystrophies, stromal dystrophies and endothelial dystrophies. Whereas some corneal dystrophies may result in few or mild symptoms and morbidity throughout a patient's lifetime, others may progress and eventually result in substantial visual and ocular disturbances that require medical or surgical intervention. Corneal transplantation, either with full-thickness or partial-thickness donor tissue, may be indicated for patients with advanced corneal dystrophies. Although corneal transplantation techniques have improved considerably over the past two decades, these surgeries are still associated with postoperative risks of disease recurrence, graft failure and other complications that may result in blindness. In addition, a global shortage of cadaveric corneal graft tissue critically limits accessibility to corneal transplantation in some parts of the world. Ongoing advances in gene therapy, regenerative therapy and cell augmentation therapy may eventually result in the development of alternative, novel treatments for corneal dystrophies, which may substantially improve the quality of life of patients with these disorders.

Artificial corneas versus donor corneas for repeat corneal transplants

BACKGROUND

Individuals who have failed one or more full thickness penetrating keratoplasties may be offered repeat corneal surgery using an artificial or donor cornea. An artificial or prosthetic cornea is known as a keratoprosthesis. Both donor and artificial corneal transplantations involve removal of the diseased and opaque recipient cornea (or the previously failed cornea) and replacement with another donor or prosthetic cornea.

OBJECTIVES

To assess the effectiveness of artificial versus donor corneas in individuals who have had one or more failed donor corneal transplantations.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2019, Issue 11); Ovid MEDLINE; Ovid Embase; LILACS (Latin American and Caribbean Health Sciences Literature database); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 4 November 2019.

SELECTION CRITERIA

Two review authors independently assessed reports from the electronic searches to identify randomized controlled trials or controlled clinical trials. Any discrepancies were resolved by discussion or consultation.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. For discussion purposes, we summarized findings from relevant comparative case series. We performed no data synthesis.

MAIN RESULTS

We did not identify any randomized controlled trials or controlled clinical trials comparing artificial corneas with donor corneas for repeat corneal transplantations.

AUTHORS' CONCLUSIONS

The optimal management for those individuals who have failed a conventional corneal transplantation is unknown. Currently, in some centers, artificial corneal devices are routinely recommended after just one graft failure, while in other centers, they are not recommended until after multiple graft failures, or not at all. To date, there have been no controlled trials comparing the visual outcomes and complications of artificial corneal devices (particularly the Boston type 1 keratoprosthesis, which is the most commonly implanted artificial corneal device) with repeat donor corneal transplantation, in order to guide surgeons and their patients. Such a trial is needed and would offer significant benefit to an ever-increasing pool of people with visual disability due to corneal opacification, most of whom are still in productive stages of their lives.

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.

The correlation between keratoconus and eye rubbing: a review

Keratoconus is a non-inflammatory disorder which is gradual in development; corneal thinning and ectatic protrusion characterizes it. Keratoconus prevalence varies between different regions depending on several factors that affecting its prevalence. There are risk factors for developing keratoconus such as demographic and environmental factors. It was suggested that eye rubbing was associated with the development of keratoconus. The main aim of this review was to summarize the literature data about keratoconus and to identify the role of eye-rubbing in the aetiology of the disease. A number of 24 articles was reviewed through the PubMed, Google Scholar and Research Gates. There are many keywords used such as keratoconus, aetiology of keratoconus, eye rubbing, keratoconus prevalence, keratoconus and eye rubbing correlation. We concluded that eye rubbing causes the thinning of keratocyte, and the degree of effect of eye rubbing depends on the period and force of performing eye rubbing. It is recommended to avoid eye rubbing to prevent keratoconus, this can be achieved by avoiding itching and treating dryness of the eye and avoiding wearing eye lenses.

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.