Central Corneal Endothelial Cell Density Research Articles

Correlations of Corneal Endothelial Morphology and Corneal Thickness With Anterior Segment Parameters in Healthy Individuals.

The purpose of this study was to investigate the associations between central corneal endothelial cell density (ECD), endothelial morphology, and corneal thickness (central corneal thickness) with the anterior chamber depth, corneal volume (CV), white-to-white (WTW) distance, mean anterior chamber angle (CAmean), and gender in healthy individuals. This observational study included 136 healthy volunteers. The ECD, coefficient of variation of cell area, and hexagonal cell appearance ratio (%Hex) were measured by means of specular microscopy. The central corneal thickness, anterior chamber depth, CV, WTW distance, and the angle width of 12 points were taken by the Pentacam HR Scheimpflug anterior segment imaging. The arithmetical mean of the 12 points was considered as the CAmean. We used mixed effect linear regression model for the statistical analysis of the data. ECD was positively correlated with CV ( P = 0.028), while after adjusting for age, it was negatively correlated with age ( P < 0.001). Coefficient of variation of cell area was positively correlated with CAmean ( P = 0.036), while after adjusting for age, it was positively correlated with age ( P < 0.001) and CAmean ( P = 0.005). Hex was negatively correlated with WTW ( P = 0.023) and CAmean ( P = 0.025), and after adjusting for age, this correlation remained the same ( P = 0.029 when correlated with WTW and P = 0.035 with CAmean). There were significant changes in the morphology of the corneal endothelial cells in eyes with wider anterior chamber angle. Greater pleomorphism and polymegethism of the corneal endothelium was observed in healthy patients with wider CAmean. Deepening of the anterior chamber as myopia progresses could render the corneal endothelium more fragile and susceptible to mechanical stress, which is an area worthy of further study.

The Protective Effect of Rho-Associated Kinase Inhibitor Eye Drops (Ripasudil) on Corneal Endothelial Cells After Cataract Surgery: A Prospective Comparative Study.

Cataract surgery poses a risk to corneal endothelial cells. This study aimed to assess the protective effect of rho-associated kinase inhibitor eye drop (ripasudil) on corneal endothelial cells after cataract surgery over 12months. We conducted a prospective, non-randomized, non-blinded comparative study including 43 patients divided into two groups: the ripasudil group (22 patients, 23 eyes) and the control group (21 patients, 21 eyes). All patients had grade 3 nuclear cataract and underwent uneventful phacoemulsification with intraocular lens implantation. In the ripasudil group, one drop of ripasudil hydrochloride hydrate (Glanatec® ophthalmic solution 0.4%) was administered three times a day for 5days. Outcome measures included central corneal thickness (CCT) and endothelial cell density (ECD), which were evaluated preoperatively and 12months postoperatively. In the ripasudil group, the median ECD was 2398 (interquartile range [IQR] 410, 2201-2611) cells/mm2 at baseline and 2262 (IQR 298, 2195-2493) cells/mm2 at 12months postoperatively. In the control group, the median ECD was 2503 (IQR 390, 2340-2730) cells/mm2 at baseline and 2170 (IQR 324, 2049-2373) cells/mm2 at 12months postoperatively. Endothelial cell loss (ECL) was 12.8% in the control group, significantly reduced to 4.5% in the ripasudil group (p = 0.001*). CCT (p = 0.042), age (p = 0.383), sex (p = 0.944), and duration of surgery (p = 0.319) were not significant factors. No adverse effects were observed in either of the groups. Incorporating ripasudil into postoperative management could help maintain corneal endothelial cell integrity and reduce cell loss after cataract surgery, potentially decreasing the need for endothelial transplantation in patients who have undergone intraocular surgeries.

The Effect of Tobacco Smoking on Corneal Endothelium and Central Corneal Thickness

We aimed to study the impact of tobacco smoking towards central corneal thickness, morphology, and corneal endothelial cell density (ECD) in healthy subjects. This cross-sectional study recruited consecutive patients who visited the Ophthalmology Clinic, Universiti Kebangsaan Malaysia Medical Centre, from April 2017 to August 2018 who were active smokers and non-smokers. Active smokers were further divided into heavy and light smokers according to the number of pack-years smoked. The nicotine dependency level was measured using the Fagerstrom test and divided into low, moderate, and severe dependency. Non-contact specular microscopy was performed. Parameters studied included the ECD, percentage of hexagonality (HEX), coefficient of variation of cell size (COV), and central corneal thickness (CCT). A total of 84 eyes from 84 subjects were included, with 42 in the smoker and 42 in the non-smoker groups. The mean age was 38.3 ± 6.7 and 39.2 ± 10.7 years in the smoker and non-smoker groups, respectively. The mean ECD, HEX, and COV were 2783 ± 316 vs. 2877 ± 333 cells/mm2, 55.0 ± 6.7% vs. 55.0 ± 7.7% and 32.7 ± 4.4% vs. 32.2 ± 4.1% in the smoker and non-smoker group, respectively. However, none were statistically significant (p&gt;0.05). The mean CCT was also not statistically different, with 532.6 ± 30.8 μm in the smoker group and 530.5 ± 30.8 μm in the non-smoker group. No statistically significant difference was found between light and heavy smokers and addiction levels. There was a statistically significant but weak negative correlation between ECD and duration of smoking (r = -.370, p = 0.016) and a weak positive correlation between COV and number of pack-years smoked (r = .344, p = 0.025). Smoking did not significantly affect corneal ECD, cellular morphology, or CCT.

Comparative assessment of the corneal endothelium following phacoemulsification surgery in patients with type II diabetes and nondiabetes

Abstract: PURPOSE: The purpose is to assess the corneal endothelial changes after phacoemulsification surgery in diabetic patients and compare with those of nondiabetic subjects. METHODS: The study compared the corneal endothelial changes in diabetics and nondiabetics after phacoemulsification surgery. The study population included 40 patients with diabetes mellitus with good glycemic control and 40 nondiabetic patients who underwent uneventful phacoemulsification surgery. Central corneal endothelial cell density (ECD), central corneal thickness (CCT), and percentage of hexagonality percentage coefficient of variation (%CV) were measured preoperatively and postoperatively (at 4 and 12 weeks) using a specular microscope. RESULTS: Mean ECD loss (%) was measured as 9.85% and 8.41% at 4 weeks and 12 weeks postoperatively in the diabetic group while ECD loss percentage was 7.09% and 5.74% in the control group at the same time intervals, respectively. Furthermore, a significant difference was noted on comparing mean ECD measurements between the two groups at the postsurgical visits (4 weeks and 12 weeks). While the CCT was found to be similar in both diabetic and nondiabetic patients, increase was observed in the values of (%CV in both the groups at postoperative 4 weeks’ and 12 weeks’ follow-up. The values of both %CV and percentage hexagonality showed statistically significant differences between the diabetic and nondiabetic group before surgery and at 4 weeks’ and 12 weeks’ postoperative examinations. CONCLUSION: The patients with diabetes suffered greater endothelial damage despite good glycemic control as compared to nondiabetic patients which indicates the necessity of far more care to protect cornea endothelium in patients with diabetes.

Do intravitreal anti-VEGF injections have an effect on corneal endothelial remodeling in children with premature retinopathy?

This study was carried out to investigate the effects of retinopathy of prematurity (ROP) and intravitreal antivascular endothelial growth factor (VEGF) injections on the corneal endothelium in the childhood period of patients who have had ROP. The material of comparative case-control clinical study consisted of patients followed up with ROP between February 2013 and February 2023. The eyes in the study group were divided into two subgroups consisting of those who received intravitreal anti-VEGF injections (subgroup 1) and those who were followed up only (subgroup 2). Central corneal endothelial cell density (ECD), coefficient of variation (CV), central corneal thickness (CCT), and pleomorphism parameters in the childhood period were evaluated by corneal specular microscopy and compared with age-matched healthy control subjects. There were 84 eyes of 42 patients with ROP in the study group and 80 eyes of 40 healthy children in the control group. Mean CCT was significantly higher in subgroup 1 and the control group than in subgroup 2 (p = 0.037), and mean ECD was significantly higher in subgroup 2 than in subgroup 1 and the control group (p < 0.001). There was no significant difference between subgroup 1 and the control group in mean ECD and CCT values (p = 1.000 for both cases). Considering that ROP patients who received intravitreal anti-VEGF injections had more advanced-stage ROP than ROP patients who were followed up only, these findings suggest that intravitreal anti-VEGF applications in ROP cases may lead to corneal endothelial parameters similar to those of healthy eyes.

Outcomes of hemi-Descemet membrane endothelial keratoplasty and phacoemulsification for the treatment of primary Fuchs' endothelial corneal dystrophy combined with cataract

This study evaluates the long-term results of surgical treatment of patients with Fuchs' endothelial corneal dystrophy and cataract. The study included 24 patients (24 eyes) with primary Fuchs' endothelial corneal dystrophy and cataract, who underwent cataract phacoemulsification with IOL implantation and of Descemet's membrane endothelial keratoplasty with a semicircular graft (hemi-DMEK). The effect of treatment was assessed by best corrected visual acuity (BCVA), central corneal thickness (CCT) and endothelial cell density (ECD). In total, surgical treatment involved 14 donor corneas that were divided in half during the preparation and isolation of the Descemet's membrane (DM). By month 12 after the surgery an increase in visual functions and graft transparency were observed in 23 patients (23 eyes) out of 24. Repeated keratoplasty was required in one case due to fibrosis of the posterior layers of recipient's corneal stroma. At 12 months postoperatively, the study group showed an increase in BCVA from 0.16±0.1 to 0.75±20, a decrease in CCT from 650.9±4.5 μm to 519.6±43.9, and a decreased in ECD from 2850.5±84.7 cells/mm2 up to 1285.5±277.2 cells/mm2. Thus, the loss of endothelial cells at one year after surgery amounted to 54.9%. The developed method for transplantation of a semicircular DM fragment provides a tissue-saving approach to endothelial keratoplasty, and considering the high percentage of transparent engraftment of grafts and complete visual rehabilitation, it can be recommended in the treatment of patients with cataract and Fuchs' endothelial corneal dystrophy.

Comparison of central corneal thickness and endothelial cell count among diabetic retinopathy and non-diabetic cases

: Diabetes is associated with alterations in the structure and functions of corneal endothelial cells. Current research has been carried out to compare the central corneal thickness and endothelial cell density in patients with diabetic retinopathy (DR) and non-diabetic (ND) individuals. : A Cross Sectional comparative research was carried out in a tertiary eye care hospital, over the period of two years from April 2021 to March 2023. Among 160 study participants, 80 cases with diabetic retinopathy (DR) and 80 non-diabetic (ND) cases as age matched control have been selected. Thorough Ophthalmic assessment was done. We have included only retinopathy cases as they have longer duration of diabetis and poorer metabolic control, for better comparison of the endothelium parameters with non-diabetics. Specular microscopy has been done in all cases for endothelial cell count evaluation and thickness of cornea has been estimated by Pachymeter. Statistical analysis was carried out by students‘t’ test by comparing the variables between two groups. : P-value was not significant for the mean age and sex distribution in the two groups. Mean endothelial cell density was lesser (2512.12±260.23cells/mm2) in DR than in ND group (2699.10±95.68cells/mm2). Mean central corneal thickness was greater (522.65±36.56μm) in DR than in ND group (486.50±18.67μm) (P&amp;#60;0.05). Also, the Co-efficient of variation percentage was more whereas the percentage of hexagonality was found to be statistically less in DR than ND group. Among DR patients, endothelial cell density was significantly reduced and central corneal thickness considerably raised when compared with ND. Our results also suggest that poor metabolic control and advanced Diabetic Retinopathy are risk factors for developing keratopathy.

Single Administration of Bimatoprost Implant: Effects on 24-Hour Intraocular Pressure and 1-Year Outcomes

To evaluate the effects of a single bimatoprost implant administration on 24-hour intraocular pressure (IOP) lowering at 8 weeks, and 1-year IOP-lowering efficacy and safety outcomes. Multicenter, open-label, 12-month, phase 3b study (NCT04285580). Adults with open-angle glaucoma or ocular hypertension. Participants (n=31) received 10-μg bimatoprost implant in the study eye on day 1; IOP (sitting and/or supine) was measured with pneumatonometry every 2 hours throughout a 24-hour period at baseline and week 8. IOP was measured by Goldmann applanation tonometry (GAT) at hour 0 (8 am±1 hour) at baseline, weeks 8 and 16, and months 6, 9, and12. The primary endpoint was the week-8 hour-matched change from baseline in habitual position IOP over 24 hours assessed with pneumatonometry. Hour 0 IOP change from baseline measured with GAT in study eyes that received no additional (rescue) IOP-lowering treatment, treatment-emergent adverse events (TEAEs), and central corneal endothelial cell density (CECD) were evaluated through 12 months. The mean (standard deviation [SD]) baseline IOP at hour 0 was 24.2 (2.70) mmHg and 25.3 (7.15) mmHg by GAT and pneumatonometry, respectively. Pneumatonometer measurements of IOP taken over 24 hours at week 8 with the participant in habitual position (sitting from 8 am to 10 pm, supine from 12 am to 6 am) showed consistent IOP lowering through the day and night and reduced fluctuation in IOP. The range in IOP measurements over 24 hours was reduced from baseline by a mean (SD) of-1.6 (2.98) mmHg. All 31 bimatoprost implant-treated participants completed the 12-month study; 23 (74%) required no rescue IOP-lowering treatment. The mean (SD) IOP reduction from baseline at month 12 in nonrescued eyes was-4.3 (3.35) mmHg. The most common TEAE was conjunctival hyperemia (incidence 35.5%, 11/31). No implant-treated eye had a ≥ 15% loss in CECD from baseline. A single intracameral administration of the bimatoprost implant lowered IOP in the habitual position consistently throughout the day and night at week 8. The majority of participants continued to have reduced IOP for 1 year without additional therapy. The 1-year safety profile was favorable. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Femtosecond laser-assisted minimally invasive lamellar keratoplasty for advanced keratoconus

Objective: To evaluate the initial safety and efficacy of femtosecond laser-assisted minimally invasive lamellar keratoplasty (FL-MILK) for advanced keratoconus. Methods: It was a case series study. Patients with advanced keratoconus who underwent FL-MILK between August 2017 and April 2020 at Shandong Eye Hospital were prospectively included. The femtosecond laser was used to create an intrastromal pocket in the recipient cornea and a lamellar cornea in the donor. The lamellar cornea was then gently inserted into the intrastromal pocket through the incision and flattened. Clinical measurements included best-corrected visual acuity, 3-mm anterior corneal mean keratometry, anterior and posterior central corneal elevation, central corneal thickness, corneal biomechanics, and endothelial cell density. The follow-up was conducted at 1 month, 12 months, and 24 months after the operation. Results: There were 33 patients (35 eyes) in the study. Twenty-six patients were male and 7 patients were female. The mean age was (20.34±5.24) years old. All patients completed 12 months of follow-up, and 25 patients (27 eyes) completed 24 months of follow-up. No epithelial ingrowth, infection, or allogeneic rejection was observed. Compared with the preoperative data, the anterior central corneal elevation significantly decreased (P<0.001), the mean keratometry significantly decreased (P<0.05), and the central corneal thickness significantly increased (P<0.001). The corneal biomechanical strength was significantly improved, with the deformation amplitude ratio at 2.0 mm decreasing from 1.39±0.14 preoperatively to 1.21±0.10 at 24 months postoperatively (P<0.001) and the stiffness parameter at the first applanation increasing from 41.49±11.47 preoperatively to 88.41±18.17 at 24 months postoperatively (P<0.001). There were no significant changes in the mean best-corrected visual acuity, posterior corneal elevation, mean spherical equivalent, and endothelial cell density (all P>0.05). Conclusions: FL-MILK may be a feasible option for advanced keratoconus. This procedure may provide a new resolution for keratoconus.

Relationship of Corneal Endothelial Morphology and Central Corneal Thickness to Age and Sex in Normal Healthy individuals in our Community

Background: Central corneal thickness and corneal endothelial morphology was studied along it's relationship with age and sex. Objective: To determine the normative data of central corneal thickness and endothelial morphology in our population. Methodology: This is a Cross-sectional study. The study was done at Ophthalmology Department, FRPMC in accordance with the declaration of Helsinki from March 2021 to August 2021 with approval from the Institutional review board. All healthy individuals aged 20 to 70 years presenting with any ocular complaints but no corneal pathology were included. Individuals with any systemic and ocular co-morbidity were excluded. After a complete ocular examination, corneal specular microscopy was done using REXAM SPM-700 corneal specular microscopes. In our study, we analyzed CCT, ECD, MCA, CV and hexagonality. The data was collected and recorded on an Excel spreadsheet and then transformed to SPSS version 22 for statistical analysis. Results: 724 eyes from 362 individuals were studied for CCT and endothelial morphology using Rexam SPM-700 microscopes. There were 241(66.6%) males and 121(33.4%) females with mean age 38.33±10.17 years. Among 724 eyes we found CCT (508.43±33.4um), ECD (2565.12±254.15cell/mm2), AVG (393.81±40.72um2), CV (39.54±6.43%), and Hexa (46.18±6.64%). Statistically, there was no significant difference between the right and left eyes of the study population as well as gender-wise. There is a statistically significant inverse correlation of ECD with age (p&lt;0.00, r:-0.19). However, a statistically insignificant inverse correlation is found for CV and Hexa with age (p&lt;0.17, r:-0.05) (p&lt;0.70, r:-0.014) respectively. Conclusion: Our study reports the normative corneal endothelial morphology and thickness in the Pakistani population attending FRPMC Ophthalmology Department. We also found that Central corneal thickness and Endothelial cell density decrease with aging and no statistical difference gender-wise.

Normal Corneal Thickness and Endothelial Cell Density in Rhesus Macaques (Macaca mulatta).

PurposeTo define the normal range of central corneal thickness (CCT) and corneal endothelial cell density (ECD) in rhesus macaques (Macaca mulatta) and the effects of age, body weight, sex, and intraocular pressure (IOP) on these parameters.MethodsOphthalmic examinations were performed on 144 rhesus macaques without anterior segment pathology. The CCT was measured via ultrasound pachymetry (USP) and specular microscopy, and the ECD was semiautomatically and manually counted using specular microscopy. Rebound tonometry was used to measure IOP. Linear regression and mixed-effects linear regression models were used to evaluate the effects of age, body weight, sex, and IOP on CCT and ECD.ResultsWe included 98 females and 46 males with an age range of 0.2 to 29.4 years. The mean CCT by USP and specular microscopy were 483 ± 39 and 463 ± 33 µm, respectively, and were statistically different (P < 0.001). The ECDs were 2717 ± 423 and 2747 ± 438 cells/mm2 by semiautomated and manual analysis, respectively. Corneal endothelial degeneration was identified in one aged rhesus macaque.ConclusionsThe mean USP and specular microscopy CCT values differed significantly, whereas the semiautomatic and manual ECD did not. The CCT was associated with the IOP and sex, whereas the ECD was associated with body weight and age (P < 0.05). As in humans, corneal disease in rhesus macaques is uncommon.Translational RelevanceEstablishing reference values is fundamental to use rhesus macaques as a model for corneal disease or to identify toxicity in studies of ocular drugs or devices.

Snail Track Lesion with Flat Keratometry in Anterior Segment Dysgenesis Caused by a Novel FOXC1 Variant.

We report the phenotype of a 15-year-old female patient with anterior segment dysgenesis (ASD) caused by a novel heterozygous loss-of-function FOXC1 variant. The proband underwent an ophthalmic examination as well as a molecular genetic investigation comprising exome sequencing, a single nucleotide polymorphism array to access copy number and Sanger sequencing to exclude non-coding causal variants. There was bilateral mild iris hypoplasia with pupil deformation and iridocorneal adhesions. In addition to these features of ASD, the corneas were flat, with mean keratometry readings of 38.8 diopters in the right eye and 39.5 diopters in the left eye. There was a snail track lesion of the left cornea at the level of the Descemet membrane. The central corneal endothelial cell density was reduced bilaterally at 1964 and 1373 cells/mm2 in the right and left eyes, respectively. Molecular genetic analysis revealed that the proband was a carrier of a novel heterozygous frameshifting variant in FOXC1, c.605del p.(Pro202Argfs*113). Neither parent had this change, suggesting a de novo origin which was supported by paternity testing. We found no possibly pathogenic variants in the other genes associated with posterior corneal dystrophies or ASD. Further studies are warranted to verify whether there is a true association between snail track lesions, corneal flattening, and pathogenic variants in FOXC1.

Fuchs heterokromik iridosiklit hastalarında kornea biyomekaniği ve kornea değerlendirilmesi

Amaç: Bu çalışmanın amacı Fuchs heterokromik iridosiklit (FHİ) tanılı gözler ile sağlıklı diğer gözlerin kornealarının ve kornea biyomekanik özelliklerinin karşılaştırılmasıdır. Gereç ve Yöntem: Fuchs heterokromik iridosiklit tanılı 14 göz (Grup 1) ve sağlıklı diğer gözler (Grup 2) çalışmaya dâhil edildi. Tüm hastalara detaylı bir oftalmolojik bakıyı takiben Ocular Response Analyzer korneal biyomekanik özellikler ve speküler mikroskobi ile santral korneal kalınlık (SKK), korneal endotelyal hücre dansitesi (KEHD) değerlendirildi. Bulgular: En iyi düzeltilmiş görme keskinliği ve intraoküler basınç istatistiksel olarak benzerdi (p değerleri sırasıyla 0,077 ve 0,557). Korneal biyomekanik parametreleri olan korneal histerezis, korneal resiztans faktör, IOPcc ve IOPg değerleri her iki grupta istatistiksel olarak benzerdi (p değerleri sırasıyla; 0,521, 0,817, 0,980 ve 0,980 idi). Ortalama santral korneal kalınlık Grup 1’de 555,57±42,95 (467-626) mikron ve Grup 2’de 556,5±37,04 (480-623) mikron olarak saptandı (p=0,959). Ortalama korneal endotel hücre dansitesi Grup 1’de 2313±420,22 (1271-2717) ve Grup 2’de 2404,42±326,75 (1566-2834) hücre/mm2 saptandı (p=0,626). Sonuç: Sağlıklı gözler ile Fuchs Heterokromik İridosiklit tanılı gözler karşılaştırıldığında kornea biyomekanik parametreleri ve korneal endotel hücre dansitesi arasında anlamlı fark saptanmamıştır. Bu sonuçlar literatürdeki birçok çalışma ile çelişmekte olup daha geniş vaka serileri ile yeni çalışmalara ihtiyaç vardır.

Cataract Surgeries in Patients with Fuchs Endothelial Dystrophy.

Patients with Fuchs endothelial dystrophy often develop visual symptoms between 50 - 60 years of age, which is the same time that the first symptoms of a developing cataract start to appear. On the other hand, in patients with a clinically significant cataract, corneal guttata may be detected by chance during a routine clinical workup. In both situations, the surgeon has to decide whether DMEK or cataract surgery should be performed alone or in combination. In the case of advanced Fuchs dystrophy with or without a clinically significant cataract, a combined surgery known as the triple procedure seems favorable as the clinical course after this procedure is the same as following sequential surgery. Furthermore, the affected patients will only have to undergo one surgery and will reach the final visual acuity much faster. Posterior lamellar keratoplasty alone can only be an option in the case of young patients with advanced Fuchs dystrophy, intact accommodation, and no signs of cataract. In the case of a clinically significant cataract combined with corneal guttata, clinical features including central corneal thickness and endothelial cell density, among others, can help to decide which surgical procedure seems to be the best. In case of cataract surgery alone, the surgeon needs to protect the corneal endothelium as well as possible. The softshell technique can help to reduce the loss of endothelial cells during cataract surgery, whereas femtosecond laser assisted cataract surgery is still controversial. The following review will discuss the most important preoperative, perioperative, and postoperative factors that need be considered in order to achieve the best result for our patients.

Transvers ve Torsiyonel Fakoemülsifikasyon ile Biaksiyel Mikroinsizyon Katarakt Cerrahisinde Saydam Korneal Kesi Değişikliklerinin Karşılaştırılması: Kohort Çalışması

Objective: To compare the effects of transverse versus torsional phacoemulsification by using the biaxial microincision cataract surgery technique on corneal structures and clear corneal incision (CCI) morphology. Material and Methods: We evaluated comparative case series of patients with moderate density nuclear cataracts who underwent biaxial microincision transverse or torsional phacoemulsification. Seventy patients have included in the study and they were divided into 2 groups: transverse and torsional. The main outcome measures included, corrected distance visual acuity, central corneal thickness, central corneal endothelial cell density, endothelial cell loss (ECL), and changes in the CCI morphology. Results: Each group comprised 35 (35 eyes) patients. Epithelial misalignment on the CCI morphology was highly significantly meaningful with the transverse group on the postoperative first day (p<0.001). Descemet membrane detachment on the first day postoperatively was high in both groups, especially in the transverse group, but the difference was not statistically significant (p=0.073). In the postoperative 3rd month, the mean ECL was 23.6% in the transverse group, and 19.0% in the torsional group, and there was no statistically significant difference between groups (p=0.187). Conclusion: In biaxial microincision cataract surgery, the corneal damage caused by transverse phacoemulsification seems to be higher compared to the torsional mode.

Interocular Symmetry and Repeatability of Central Corneal Thickness and Corneal Endothelial Cell Morphology and Density in Healthy Eyes of Congolese

ABSTRACT Purpose To determine the limits of normal interocular symmetry and the repeatability of central corneal thickness (CCT) and endothelial cell morphology and density. Methods Two hundred and seventy-eight subjects (age: 10.9–80.7 years) with healthy eyes were studied. CCT as well as endothelial cell morphology and density were measured by non-contact specular microscopy. Three measurements were obtained per eye per participant. Upper and lower tolerance limits of normal interocular symmetry were defined as the 2.5th and 97.5th percentiles of the interocular differences in CCT, endothelial cell density (CECD), coefficient of variation (CoV), hexagonality, and cell size. Repeatability was determined using the intraclass coefficient correlation (ICC), the coefficient of variation (CV), and the test–retest variability standard deviation (TRTSD). Results The mean interocular differences were −1.05 ± 17.5 µm (p = .32) for CCT and 0.5 ± 90.8 cells/mm2 (p = .76) for CECD. The 2.5th and 97.5th percentiles of the interocular differences were −13.9 and 15.4 µm for CCT and −177.4 cells/mm2 to 182.0 cells/mm2 for CECD. Only interocular difference in CoV correlated weakly with age (r = −0.22, P < .001). ICCs were 0.93 (95% CI: 0.89–0.96, P < .001) for CCT and 0.95 (0.94–0.96, P < .001) for CECD. CV and TRTSD were 1.2% ± 5.3% and 4.4 ± 3.4 µm for CCT and 2.4% ± 3.9% and 17.7 ± 7.7 cells/mm2 for CECD, respectively. Conclusions CCT and CECD showed good repeatability and interocular symmetry in normal Congolese subjects. Absolute interocular differences in CCT and CECD exceeding 15.5 µm and 182 cells/mm2, respectively, should be considered suspicious and investigated. When comparing two intrasession measurements from the same eye, a difference of approximately 4.5 µm in CCT and 18 cells/mm2 or greater may be considered statistically significant.

Overestimation of corneal endothelial cell density by automated method in glaucomatous eyes with impaired corneal endothelial cells

PurposeTo determine between-method differences in corneal endothelial cell parameters using center and automated methods of non-contact specular microscopy (CellCheck software of Konan, Inc.) in glaucomatous eyes.MethodsWe analyzed the central corneal endothelial cell density (ECD) of 245 glaucomatous eyes using center (ECD-Ce) and automated methods (ECD-Au). Based on the ECD-Ce, we allocated subjects to Groups 1 to 10 (at 250 cells/mm2 intervals) and evaluated the ECD, coefficient of variation in cell area (CV), and percentage of hexagonal cells (HEX).ResultsThere was a close correlation (r = 0.91) between the ECD values measured using both methods. However, ECD-Au were significantly higher than those measured by the center method when ECD-Ce was less than 2500 (in Groups 1 to 8; P < 0.001 to P = 0.006). The regression equation of (ECD-Au—ECD-Ce) = 1028–0.397*ECD-Ce shows greater deviation in eyes with lower ECD, and this difference became 0 when ECD -Ce was 2593 cells/mm2. None of the 44 subjects with an ECD-Ce of < 1000 cells/mm2 recorded an ECD-Au < 1000 cells/mm2. Compared with the center method, the automated method had higher and lower median CV and HEX values, respectively (P < 0.001). The between-method differences in both CV and HEX were negatively correlated with ECD-Ce (r = −0.49, P < 0.001 and r = −0.25, P < 0.001, respectively).ConclusionThe automated method of the CellCheck software overestimates ECD in eyes with lower ECD values and may overlook risk of corneal decompensation.

Corneal endothelial cell changes and surgical results after Ahmed glaucoma valve implantation: ciliary sulcus versus anterior chamber tube placement

We compared the changes in corneal endothelial cells and surgical outcomes after Ahmed glaucoma valve (AGV) implantation with the valve tip inserted either into ciliary sulcus (CS) or anterior chamber (AC). We retrospectively reviewed the medical records of patients treated with CS AGV (n = 24) and AC AGV (n = 38). We compared the preoperative and postoperative central corneal endothelial cell density (ECD), endothelial cell coefficient of variation (CV), best-corrected visual acuity, intraocular pressure (IOP), number of glaucoma medications, and postoperative complications in the two groups. Both groups had similar baseline characteristics and follow-up period. At the last follow-up, the AC AGV group had significantly higher mean monthly ECD loss (17.47 ± 11.50 cells/mm2 vs. 6.40 ± 7.69 cells/mm2, p < 0.0001) and greater proportion of mean monthly ECD loss than the CS AGV group (0.84 ± 0.53 vs. 0.36 ± 0.39%, p < 0.0001). Both groups had similar mean monthly CV changes. The qualified success rates at 2 years were 83.3% and 76.3% for the CS AGV and AC AGV groups, respectively. Although similar surgical outcomes including visual acuity, IOP, number of glaucoma medications, and postoperative complications were obtained following CS AGV and AC AGV, corneal ECD loss was higher in the AC AGV group. Thus, CS AGV may be a better surgical option than AC AGV.

Association Between Anterior Chamber Angle and Corneal Endothelial Cell Density in Chronic Angle Closure.

PurposeTo study the association between corneal endothelial cell density (ECD) and degree of anterior chamber angle (ACA) opening in eyes with chronic angle closure glaucoma.MethodsThe study was conducted at JEC Eye Hospitals in Indonesia. Treatment-naïve patients aged ≥40 years with IOP >21 mmHg and peripheral anterior chamber depth (ACD) grade 2 or less by Van Herick’s technique were recruited. Trabecular iris angle (TIA; degree) was measured using anterior segment optical coherence tomography (AS-OCT) and classified as: grade 1 ≤10°, grade 2 11–20°, and grade 3 >20°. Noncontact specular microscopy was performed, and the following corneal parameters were obtained:ECD (cells/mm2), coefficient of variation (CV; μm2/cell), percentage of hexagonal cells, and central corneal thickness (CCT; μm).ResultsA total of 52 eyes from 52 subjects were recruited (16 grade 1 TIA, 24 grade 2 TIA, and 12 grade 3 TIA). Presenting IOP was not significantly different between groups. The median central corneal ECD was 2684.5 (1433–2934), 2587.0 (1902–3103), and 2441.0 (1659–3005) cells/mm2 in grade 1, 2, and 3 TIA, respectively, with no significant differences across the groups (P = 0.67). The CV was lowest in grade 3 TIA (36.4 ± 7.2 μm2/cell), and highest in grade 1 TIA (38.3 ± 9.6 μm2/cell), but the differences were not significant (P = 0.74). Likewise, the percentage of hexagonality and CCT was not significantly different. TIA was not correlated with IOP but was modestly correlated with age.ConclusionThe corneal ECD and morphological characteristics such as CV and hexagonality were not significantly different across various TIA grading in chronic angle closure. This may reflect the lack of chronic and gradual IOP insult on corneal endothelial parameters as TIA did not show direct effect towards IOP.

Comparison of Central Corneal Thickness and Endothelial Cell Density in Patients with Various Types of Glaucoma and Patients without Glaucoma: A Case-control Study

Introduction: Corneal affection in glaucoma patients is very high due to various risk factors that may lead to unforeseen and unplanned deleterious effects on the cornea leading to vision loss. Accurate intraocular pressure determination requires corneal thickness measurement and uncontrolled intraocular pressures, use of long term medication, intra ocular surgeries including cataract and glaucoma shunt surgeries may cause significant endothelial loss. Therefore, adequate planning and management and follow-up in these patients is required weighing all the long term consequences and emphasis the need for implementing adequate precautions. Aim: To evaluate and compare the Central Corneal Thickness (CCT) and corneal Endothelial Cell Density (ECD) in patients with glaucoma and without glaucoma by specular microscopy. Materials and Methods: A case-control study conducted in a Shekar Eye Hospital, Bengaluru, Karnataka, India, was conducted from August 2016 till April 2018 on a total 182 eyes from 182 patients were evaluated comprising of 91 cases and 91 controls. All participants underwent a detailed ophthalmological examination including slit lamp biomicroscopy, Intraocular Pressure (IOP) measurement, and CCT and ECD measurement by Tomey EM 3000 noncontact specular microscopy. The Statistical analysis was completes using Statistical Package For the Social Sciences (SPSS) 18.0 and R environment version 3.2.2 software’s. Results: The CCT of the glaucoma patients and the controls showed no significant difference (p-value=0.172). The CCT was comparatively thicker in Ocular Hypertension (OHTN) patients and thinner in Normal Tension Glaucoma (NTG) however statistical significance was not established. The mean ECD of controls was 2509.05±298.48 (cells/mm3) and that of cases was 2465.68±392.91 (cells/mm3) (p-value=0.404). The difference in the ECD amongst the glaucoma subgroups was not statistically significant (p-value=0.588). However, a lower ECD were seen in Pseudoexfoliation Glaucoma (PXG) and Primary Angle Closure Glaucoma (PACG) subgroups. Conclusion: No significant difference was found in CCT and endothelial cell in cornea of patients with and without glaucoma. Normal Tension Glaucoma (NTG) patients have comparatively thinner corneas and OHTN patients had thicker corneas. There was no significant correlation established between ECD of Normal corneal vs. Glaucoma and its subgroups.