Changing indications and techniques for corneal transplantations at a tertiary referral center in Turkey, from 1995 to 2014

Endothelial keratoplasty: indications and outcomes in a tertiary care center in Lebanon

OBJECTIVE

This study aims to assess the indications and outcomes of Descemet membrane endothelial keratoplasty (DMEK) surgeries in Lebanon, where tissues are imported. Focusing on visual acuity (VA) and central corneal thickness (CCT).

METHODS

This retrospective chart review analyzed 86 DMEK surgeries performed on 78 patients between 2016 and 2023, examining CCT and VA measured preoperatively and up to one-year post-DMEK. Variables of interest included the rate of rebubbling, intraocular pressure (IOP), tissue preparation methods (preloaded, surgeon-prepared, or pre-stripped/precut tissue), donor age, donor endothelial cell count, time from death to preservation, time from preservation to surgery, and time from death to transplant. The goal was to explore the relationships between these variables and the clinical outcomes.

RESULTS

The most common indication for DMEK was pseudophakic or aphakic bullous keratopathy (PBK), followed by graft failure and Fuchs' endothelial corneal dystrophy (FECD). Significant improvements in VA and CCT were observed postoperatively (p < 0.001 and p ≤ 0.015 respectively). The mean IOP was 16.8 mmHg at baseline and 17.2 mmHg at 1 year post-operatively. The mean LogMAR score was 1.46 ± 0.16 at baseline, improving to 0.87 ± 0.21 at the 1-year follow-up. The rebubbling rate was 28.7%. Patients who required rebubbling had significantly higher central corneal thickness (CCT) during the first month (p = 0.027), but this difference was not observed over the course of the entire year. However, a notable incidence of postoperative new onset elevation in IOP was documented, affecting approximately 36.5% of patients.

CONCLUSION

Despite challenges posed by limited resources and economic constraints in Lebanon, DMEK surgery has shown promising outcomes in improving VA and CCT. Vigilant monitoring and management of postoperative complications, particularly elevated IOP, is essential. Addressing systemic barriers to healthcare access and enhancing corneal transplantation infrastructure are crucial for ensuring equitable delivery of advanced ophthalmic care in resource-limited settings.

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.

Revisiting the oil droplet sign in keratoconus: Utility for early keratoconus diagnosis and screening

PURPOSE

An annular dark shadow (ADS) reflex has been observed while performing direct ophthalmoscopy on subjects with keratoconus. This study describes a method that may serve as a diagnostic technique for early keratoconus and may be used as a quantitative measure of severity.

METHODS

Healthy keratoconic subjects and keratoconus suspects underwent corneal tomography and a full ocular examination. Keratoconus severity was graded based on Belin ABCD criteria. An iPhone camera was connected to a direct ophthalmoscope to take a picture of the eye. The height of the ASD was measured using the AutoCAD software. Differences between subject groups were evaluated by chi-squared and Mann-Whitney tests. Spearman correlation compared ocular parameters and the height of the ADS. A multiple stepwise linear regression was used to predict the height of the ADS based on clinical parameters.

RESULTS

Fifty-eight subjects participated in this study: 37 healthy controls (37 eyes) and 21 keratoconics or keratoconus suspects (37 eyes). The ADS was present in all keratoconic and keratoconus-suspect eyes but in none of the controls. The height of the ADS was significantly correlated with keratoconus severity. Front corneal surface root mean square of higher order aberrations, sphere and anterior radius of curvature from the front apex curve are significant predictors of the height of the ADS.

CONCLUSIONS AND RELEVANCE

The ADS may be a useful method to diagnose keratoconus and keratoconus-suspect cases and serve as a grading and follow-up method for tracking disease severity.

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.

Changing trends in the corneal transplantation and the impact of the COVID-19 pandemic on corneal transplant recipient selection

PURPOSE

The aim of this study was to analyze the trends in the major indications and types of keratoplasty over a 15-year period and to determine the effect of the coronavirus disease-2019 (COVID-19) pandemic on the selection of corneal transplant recipients at a tertiary referral center in Turkey.

METHODS

We retrospectively reviewed the data of patients who underwent keratoplasty at the center from January 2006 to March 2021. The keratoplasty indications and types of surgery were evaluated after classification into three groups (period I - January 2006-December 2012; period II - January 2013-March 2020; COVID-19 period - April 2020-March 2021).

RESULTS

A total of 5016 corneal transplants were performed in 3862 patients. Lamellar keratoplasty (LK) techniques were found to demonstrate a statistically significantly increasing trend compared to penetrating keratoplasty in the period between 2006 and 2021 (χ² = 240.55, P < 0.001). The top 4 indications over the 15-year period were aphakic/pseudophakic bullous keratopathy (BK) (1105, 22%), keratoconus (1085, 21.6%), regraft (1084, 21.6%), and keratitis (645, 12.8%). The most common keratoplasty indication during the COVID-19 period was regraft (27, 54.0%), followed by BK (13, 26.0%) and corneal perforation (5, 10%).

CONCLUSION

BK was the most common keratoplasty indication at our clinic during the 15-year period. LK rates have been found to increase in recent years, although still not reaching the rates of developed countries. There was a marked decrease in the number of keratoplasties during the COVID-19 pandemic and patients requiring urgent keratoplasty or those who suffered from a painful eye were prioritized.

Detailed phenotypic description of stromal corneal dystrophy in a large pedigree carrying the uncommon TGFBI p.Ala546Asp pathogenic variant

PURPOSE

The purpose of this study is to describe the corneal clinical spectrum and the intrafamilial phenotypic differences in an extended pedigree suffering from stromal corneal dystrophy due to the rare p.Ala546Asp mutation in TGFBI.

METHODS

A total of 15 members from a four-generation Mexican family were ascertained for clinical and genetic assessment. All individuals underwent slit-lamp biomicroscopic examination and an extensive ophthalmological examination including corneal topography (OCULUS Pentacam® AXL), corneal biomechanics (OCULUS Corvis ST), and corneal confocal biomicroscopy (Heidelberg Engineering®). A total of 10 individuals carried the heterozygous c.1637C>A (p. Ala546Asp) mutation at TGFBI exon 12.

RESULTS

Nine out of 10 mutation positive patients were available for clinical characterization. The mean age was 35.5 years, with the youngest and the eldest ones being 3 years old and 62 years old, respectively. The median age of onset of the symptoms was 19.7 years. Five (55.6%) patients presented with a predominantly granular corneal dystrophy type 2 (GCD2) phenotype, one presented with a lattice corneal dystrophy (LCD) phenotype, and one with a granular corneal dystrophy type 1 (GCD1) phenotype. Interestingly, two mutation positive subjects had no clinical deposits in the cornea, demonstrating incomplete penetrance of the disorder in this family.

CONCLUSIONS

Clinical differences in corneal phenotypes within this CD family and with other pedigrees carrying the same TGFBI genetic defect could be explained by the age of clinical examination of individual patients and/or by the presence of genetic and/or environmental modifiers.

Changing Indications for Corneal Transplantations in Southern Taiwan From 2008 to 2018

OBJECTIVES

To investigate the changing indications for corneal transplantations in southern Taiwan from 2008 to 2018 and compare the results with those of other previous studies.

METHODS

We retrospectively reviewed the records of patients who underwent corneal transplantations from January 2008 to December 2018 at Kaohsiung Veterans General Hospital. The patients' age, sex, indication for corneal transplantation, and the surgical technique were recorded and analyzed.

RESULTS

In total, 336 patients (421 eyes) were included in our study from January 1, 2008, to December 31, 2018. The mean age was 63.6±15.3 years; 371 penetrating keratoplasty (88.1%), 35 deep anterior lamellar keratoplasty (8.3%), and 15 Descemet-stripping automated endothelial keratoplasty (3.6%) were performed. The leading indication for corneal transplantation was regraft (n=103, 24.5%), followed by bullous keratopathy (n=82, 19.5%), corneal scar and opacity (n=79, 18.8%), keratitis (n=59, 14.0%), corneal dystrophy (n=58, 13.8%), other indications (n=26, 6.2%), and keratoconus (n=14, 3.3%).

CONCLUSION

The indications for corneal transplantations changed with time in Taiwan. Regraft was the leading indication, but there was a decreasing trend over time. The proportion of bullous keratopathy increased significantly over the past decade and is the second most common indication, similar to the most developed countries. Both corneal scar and opacity, and keratitis showed a decreasing trend of occurrence compared with a previous study in Taiwan. The proportion of keratoconus remained low, making it the least common indication for corneal transplantation.

Resuturing after penetrating keratoplasty without trauma: Indications and results

PURPOSE

To determine the indications, frequency, influential factors and clinical outcomes of resuturing in an atraumatic setting after penetrating keratoplasty (PK).

METHODS

Medical records of all patients who underwent resuturing in the absence of traumatic wound dehiscences after PK between January 1, 2007 and December 31, 2015 were reviewed. The cases were divided into 2 groups: patients with suture-related problems underwent mandatory resuturing (mandatory group), and patients with post-PK ectasia or a progressive increase in K values and surgically induced astigmatism underwent optional resuturing (Optional group). Patient demographics and surgical indications for PK, reasons for and frequency of resuturing, time between PK and resuturing, and clinical outcomes were evaluated.

RESULTS

The frequency of resuturing was 9.03% (59 of 633), and the mean age was 39.15±17.80 years. The most common indication for PK was keratoconus (42.4%) and the interval between PK and resuturing ranged from 0.03 to 32 months. The underlying cause leading to resuturing was suture-related problems in 43 eyes (72.9%), development of ectasia or progressive steepening of the K values and surgically induced astigmatism in 16 eyes (27.1%). The mean visual acuity increased, the K value and astigmatism decreased significantly following resuturing in both the mandatory group and the Optional group (P≤0.2). The decrease in astigmatism and K values was more marked in the Optional group, as expected (P≤0.001).

CONCLUSION

While resuturing is essential in order to obtain wound integrity in the setting of dehiscence, it is effective in terms of achieving higher visual acuities and lower astigmatism and K values in high astigmatism and post-PK ectasia cases.

Indications and Surgical Techniques for Corneal Transplantation at a Tertiary Referral Center

Purpose

The study aimed to review the indications and techniques for corneal transplantation at a tertiary referral center over a 5-year period.

Methods

Records of patients who underwent corneal transplantation at Khalili Medical Center, Shiraz, Iran from September, 2012 to September, 2017 were reviewed.

Results

A total of 1149 eyes of 956 patients underwent corneal transplantation. The most common indication was infectious corneal ulcers (n = 296, 25.8%), followed by keratoconus (n = 243, 21.1%), bullous keratopathy (n = 219, 19.1%), failed grafts (n = 117, 10.2%), non-herpetic corneal scars (n = 113, 9.8%), corneal stromal dystrophies (n = 33, 2.9%), pellucid marginal degeneration (n = 31, 2.7%), and trauma (n = 26, 2.3%); other indications included thin descemetocele, post-herpetic corneal scar, endothelial corneal dystrophies, anterior segment dysgenesis, corneal ectasia after laser in situ keratomileusis, and corneal fibrosis. Corneal transplantation techniques included penetrating keratoplasty (PKP, n = 789, 68.7%), deep anterior lamellar keratoplasty (DALK, n = 187, 16.3%), Descemet's stripping automated endothelial keratoplasty (n = 171, 14.9%), and keratolimbal allograft (n = 2, 0.1%) in descending order. In children (aged ≤18 years), the most common indication was keratoconus (n = 32, 41.6%), and the most common technique was PKP (n = 50, 64.9%). In patients aged 19-27 years, the most common indication was keratoconus (n = 89, 64.5%), and the most common technique was PKP (n = 75, 54.4%).

Conclusion

Infectious corneal ulcer was the most common indication, and PKP was the most prevalent technique in patients undergoing corneal transplantation. DALK was an emerging alternative surgical treatment in patients with corneal disorders in which corneal endothelium is spared.

Indications and techniques of corneal transplantation in a referral center in Colombia, South America (2012-2016)

PURPOSE

To describe the indications and techniques of corneal grafting in a tertiary institution in a middle-sized city in Colombia.

METHODS

A retrospective review of surgical reports and medical records of patients undergoing keratoplasty from January 2012 to December of 2016.

RESULTS

A total of 346 eyes from 316 patients were included. The first three indications for keratoplasty were: bullous keratopathy (BK) with 46.2% of the cases, active infectious keratitis (22.3%) and the group of corneal dystrophies and degenerations, including Fuchs' endothelial dystrophy (9%). Keratoconus was in the sixth place (4.9%). 73.3% of the procedures were penetrating keratoplasties (n = 255), 21.7% posterior lamellar (n = 75) and 3.5% anterior lamellar (n = 12). While in 2012, 25 cases of endothelial grafts were performed, only 13 were done in 2016.

CONCLUSIONS

BK was the first cause of keratoplasty with almost half of the cases, and keratoconus was relegated to sixth place with less than 5%. In comparison, in a study from eye banks from the US, BK was the second and keratoconus was the third indication for corneal grafts. The frequency of endothelial lamellar techniques in our institution decreased from 2012 to 2016. This could have been related to both the long time that the patients had to be on a waiting list, which made them unsuitable candidates for this technique, due to stromal fibrosis, and to the fact that surgeons of our institution had less experience with posterior endothelial grafting than with penetrating keratoplasties.