Endothelial Cell Density Measurements Research Articles

Ten-Year Clinical Outcomes of V4c Implantable Collamer Lens Implantation: Longitudinal Analysis of Visual Acuity, Endothelial Cell Density, and Vault Dynamics

This study aimed to evaluate the long-term clinical outcomes of V4c Implantable Collamer Lens (ICL) implantation for myopia correction over a 10-year period. Retrospective interventional case series METHODS: This retrospective interventional study involved 103 myopic eyes from 54 patients. Visual outcomes, including visual acuity and manifest refraction were assessed. Annual measurements of endothelial cell density (ECD), vault, anterior chamber depth, and intraocular pressure were analyzed using mixed-effects models. At the 10-year follow-up, the mean Logarithm of the Minimum Angle of Resolution (logMAR) uncorrected distance visual acuity and corrected distance visual acuity (CDVA) were -0.037 ± 0.052 and -0.041 ± 0.046, respectively. The mean efficacy and safety indices were 1.11 ± 0.13 and 1.12 ± 0.12. A loss of one line of CDVA occurred in 2% of cases, while 59% gained one or more lines. Postoperative manifest refraction spherical equivalent (MRSE) was within ±0.5 diopters (D) and ±1.0 D in 74% and 99% of cases, respectively, with a mean MRSE of -0.19 ± 0.41 D. Data for ECD and vault fit an exponential decay model, demonstrating a continuous yet gradually slowing decrease over time. Decay rates were 0.012 ± 0.001 per year for ECD and 0.056 ± 0.003 per year for the vault. Notably, ECD lower outliers had significantly lower preoperative ECD values. There were no instances of cataract formation, angle closure, glaucoma, or ICL removal throughout the study. The 10-year outcomes of V4c ICL implantation demonstrate effective and safe visual results. Both ECD and vault exhibit exponential decay patterns over the decade. Patients with lower preoperative ECD values require careful post-implantation monitoring.

Automatic Determination of Endothelial Cell Density From Donor Cornea Endothelial Cell Images.

To determine endothelial cell density (ECD) from real-world donor cornea endothelial cell (EC) images using a self-supervised deep learning segmentation model. Two eye banks (Eversight, VisionGift) provided 15,138 single, unique EC images from 8169 donors along with their demographics, tissue characteristics, and ECD. This dataset was utilized for self-supervised training and deep learning inference. The Cornea Image Analysis Reading Center (CIARC) provided a second dataset of 174 donor EC images based on image and tissue quality. These images were used to train a supervised deep learning cell border segmentation model. Evaluation between manual and automated determination of ECD was restricted to the 1939 test EC images with at least 100 cells counted by both methods. The ECD measurements from both methods were in excellent agreement with rc of 0.77 (95% confidence interval [CI], 0.75-0.79; P < 0.001) and bias of 123 cells/mm2 (95% CI, 114-131; P < 0.001); 81% of the automated ECD values were within 10% of the manual ECD values. When the analysis was further restricted to the cropped image, the rc was 0.88 (95% CI, 0.87-0.89; P < 0.001), bias was 46 cells/mm2 (95% CI, 39-53; P < 0.001), and 93% of the automated ECD values were within 10% of the manual ECD values. Deep learning analysis provides accurate ECDs of donor images, potentially reducing analysis time and training requirements. The approach of this study, a robust methodology for automatically evaluating donor cornea EC images, could expand the quantitative determination of endothelial health beyond ECD.

The effect of epilepsy and anti-epileptic drugs on the anterior and posterior segment of the eye

ABSTRACT Clinical relevance Understanding the causes of visual symptoms in epilepsy patients is important for early diagnosis and taking precautions. Background The aim of this study is to evaluate the anterior and posterior segment parameters in patients with generalized tonic-clonic epilepsy (GTCE). Methods This retrospective study included 50 eyes of 50 patients with GTCE and 55 eyes of 55 healthy controls. For all participants, detailed ophthalmic examinations were obtained from the files of patients. Anterior segment parameters were measured using corneal topography and non-contact specular microscopy, and posterior segment parameters were measured using swept-source optical coherence tomography. Results The mean age of the patients with GTCE was 43.3 ± 13.2 years, and in the healthy controls it was 47.6 ± 10.7 years (p = 0.405). In GTCE patients, 34 patients were treated with monotherapy (MT) and 16 patients with polytherapy (PT). Central macular thickness (CMT) was statistically significantly thin in GTCE patients (p = 0.001). The average and four quadrants (superior, inferior, nasal, temporal) retinal nerve fibre layer (RNFL) were thinner in GTCE patients than in the healthy controls, but there was no statistically significant difference (p > 0.05, all). The central corneal thickness was statistically significantly thin in GTCE patients (p = 0.04). Endothelial cell density (ECD), endothelial cell number (ECN), and average cell area (ACA) were statistically significantly lower in GTCE patients than in the healthy controls (p < 0.05, all). Although the CMT, average, and four-quadrants RNFL were thinner in the PT group compared to the MT group, no statistically significant difference was observed (p > 0.05, all). Total high-order aberrations (HOAs) were 0.6 ± 0.4 in the MT group and 0.4 ± 0.1 in the PT group (p = 0.01). ECD, ECN, and ACA measurements were observed to be lower in the PT group compared to the MT group, but no statistically significant difference was detected (p > 0.05, all). Conclusion There could be statistically significant differences between GTCE patients and healthy controls in anterior and posterior segment parameters. This situation may be due to the epilepsy itself or to the antiepileptic drugs.

Corneal endothelial cell morphology in children with autosomal recessive Alport syndrome: a longitudinal study

ABSTRACT Purpose To evaluate the corneal endothelial cell morphology in children with autosomal recessive Alport syndrome (ARAS). Methods This is a longitudinal, prospective cohort study that evaluated pediatric patients with genetically diagnosed ARAS. Fifty-eight eyes of 29 pediatric patients (12 patients, 17 controls) underwent a full ophthalmic examination. Corneal endothelial cell density (ECD) (cells/mm²), coefficient variation (CV) of cell area (polymegathism), the percentage of hexagonal cells (HEX) (pleomorphism), and central corneal thickness (CCT) were analyzed automatically using a noncontact specular microscopy. Results The mean ECD was 2904 ± 355.48 cell/mm² in the ARAS group and 3263.20 ± 261.71 cell/mm² in the control group (p = 0.004). In the ARAS group, the mean CV was 46.53 ± 10.43, which was significantly higher than that in controls (p = 0.026). The mean HEX was 48.86 ± 14.71 in the ARAS group and 59.06 ± 10.64 in the control group (p = 0.038). The mean CCT was 565.26 ± 39.77 µm in the ARAS group and 579.66 ± 31.65 µm in the control group (p = 0.282). The comparison of endothelial cell characteristic of the ARAS group with 1-year follow-up is as follows: The mean ECD decreased from 2904 ± 355.48 cell/mm² to 2735 ± 241.58 cell/mm² (p = 0.003). The mean CV increased from 46.53 ± 10.43 to 47.93 ± 10.50 (p = 0.471). The mean HEX decreased from 48.86 ± 14.71 to 48.50 ± 10.06 (p = 0.916). The mean CCT decreased from 565.26 ± 39.77 µm to 542.86 ± 40.39 µm (p = 0.000). Conclusion Measurement of ECD and percentage of hexagonality can also be used as an indicator of the health of the corneal endothelium. In this study, the mean ECD and HEX were significantly lower in ARAS group than in age-matched pediatric controls. Polymegathism, which reflects cellular stress, was statistically significantly higher in ARAS group. The mean ECD and CCT decreased significantly at 1-year follow-up. This study may demostrated that endothelial damages and stress in ARAS patients appear in childhood and show a rapid increase with age.

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.

Donor Cornea Storage Temperature: Investigation of the Time Period Immediately Before Cornea Transplantation Surgery

Purpose: Donor cornea storage temperature seems to affect tissue viability; however, the time period between removal from storage and transplant surgery has not been explored. We investigated the possible impact time at room temperature in the operating room may have on endothelial cell density (ECD) and corneal thickness (CT). Methods: In our simulation, transplant-ineligible corneas underwent 1 of 4 room temperature protocols. ECD (by specular microscopy) and CT (by anterior segment optical coherence tomography [OCT]), measured before and after protocols, were used to explore possible effects of time at room temperature. Control group tissue resided at room temperature only long enough for warming and subsequent ECD and CT measurements. Results: Corneas underwent one of the following protocols: 1) 17 (±1) minutes at room temperature (for baseline OCT measurements; n = 13) followed by 23 minutes at 35°C (to facilitate specular imaging, conducted for all 4 protocols), 2) 60 (±1) minutes (1 hour; n = 8) at room temperature, 3) 187 (±1) minutes (approximately 3 hours; n = 7) at room temperature, and 4) 416 (±1) minutes (approximately 7 hours; n = 7). Statistical analysis showed no significant difference in ECD change (P = 0.353) or CT change (P = 0.415) between protocol groups. Controlling for donor age and death-to-preservation time rendered no statistical significance. Conclusions: Time at room temperature did not seem to significantly influence ECD or CT measured soon after warming. Studies exploring ECD postoperatively and long-term graft survival are needed to assess the possible clinical impact of preoperative time at room temperature.

Descemet Membrane Endothelial Keratoplasty: 10-Year Cell Loss and Failure Rate Compared With Descemet Stripping Endothelial Keratoplasty and Penetrating Keratoplasty.

The aim of this study was to assess long-term endothelial cell loss (ECL) and graft failure with Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping endothelial keratoplasty (DSEK) versus penetrating keratoplasty (PK) performed for the same indications (primarily Fuchs dystrophy and pseudophakic corneal edema) in the Cornea Donor Study. This retrospective study included consecutive primary DMEK (529 recipients, 739 eyes) and DSEK cases (585 recipients, 748 eyes) with 1 or more endothelial cell density (ECD) measurements at 6 months to 16 years. Main outcomes were ECD, longitudinal ECL, and graft failure. Between 6 months and 8 years the ECD declined linearly by approximately 118 cells/mm2/yr after DMEK and 112 cells/mm2/yr after DSEK. Beyond 8 years postoperatively the rate of decline slowed substantially. Selective dropout from graft failure did not significantly affect the ECD trend. At 10 years, median ECL (interquartile range) was 63% (45, 73) with DMEK, 68% (48, 78) with DSEK, and 76% (70, 82) with PK (P = 0.01 DMEK vs. DSEK, P <0.001 DMEK vs. PK, and P < 0.001 DSEK vs. PK). The proportion of surviving grafts with 10-year ECD <500 cells/mm2 was 1.4% with DMEK, 7.3% with DSEK, and 23.9% with PK. The cumulative risk of graft failure between 6 months and 10 years was 5% with DMEK, 11% with DSEK, and 19% with PK (P < 0.001). Compared with PK and DSEK, DMEK had significantly lower ECL and significantly lower risk of secondary graft failure through 10 years.

Corneal endothelial validation in the eye bank: differences in automated methods and repeatability

To evaluate reproducibility of endothelial cell density (ECD) measurements using the Konan Cell Check D in donor corneas by two different ophthalmologists and to compare the two automated cell count methods (center and flex-center) available in the software of this specular microscope. ECD values were quantified in 54 donor corneas by two independent investigators using the Cell Check D (Konan Medical USA Inc) with both automated cell count methods. In the center method, at least 30 contiguous cells are marked. For the flex-center method, an area is delineated and only the cells within the designated area are counted. The mean ECD was 2473.81±378.22 cells/mm2. Good ECD intergrader reproducibility for the center (ICC=0.821) and the flex-center method (ICC=0.784) were noted. Poor reliability was observed for coefficient of variation and hexagonality (ICC≤0.265). When both methods for ECD analysis were compared, a moderate correlation for the two independent graders using the two manual (center and flex-center) methods was detected (correlation coefficient of 0.678 and 0.745 for each of the investigators). Comparison between methods yielded significantly higher ECD with the flex-center method (P=0.013). When corneas were divided by ECD, those under 2200 cells/mm2 and those between 2200 and 2700 cells/mm2 also had significantly higher ECD with the flex-center method (P<0.022). ECD values are reproducible with both methods, although the flex-center method ECDs tend to be higher, particularly in cases of low ECD. Eye banks and surgeons should exercise caution in making decisions based only on small differences in ECD.

Phacoemulsification with IOL implantation at a critical level of corneal endothelial cells

BACKGROUND: Cataract phacoemulsification is one of the most frequently performed surgical procedures, and a decrease in the corneal endothelial cell density (ECD) is the main postoperative complication leading to visual impairment. The average cell loss after phacoemulsification is 4.0112.94% within a year, and within 2 months 5.29.1%. The use of viscoelastics helps to reduce this loss, but it is impossible to completely prevent it.&#x0D; AIM: Сomparison of ECD in the pre- and postoperative period of phacoemulsification using viscoelastic of different percentages at a critical level of corneal endothelial cells.&#x0D; MATERIALS AND METHODS: The study included 60 eyes with emmetropic refraction: in the first group: 30 eyes with initial cataract and low ECD level (1694/1218 cells/mm2), an apyrogenic moderately cohesive viscoelastic 1.6% sodium hyaluronate solution (Kogevisk, Solopharm) was used, in the second group: 30 eyes with mature cataract and ECD level (1646/1183 cells/mm2) an apyrogenic, highly purified viscoelastic was used, consisting of medium-molecular fractions of chondroitin sodium sulfate 4% and sodium hyaluronate 3% (Adhevisk, Solopharm). Before surgery and a month after surgery, patients were tested for uncorrected visual acuity in the distance, ECD measurements, and intraocular pressure measurement.&#x0D; RESULTS: In phacoemulsification with IOL implantation, the use of viscoelastics of different percentages shows that the condition of the cornea remained stable a month after surgery. Postoperative ECD loss in all clinical cases, regardless of the stage of cataract, was less than 3%.&#x0D; CONCLUSIONS: Viscoelastics allow to solve the tasks set: in the case of cohesive maintaining the depth of the anterior chamber and the width of the pupil, adhesive protecting the corneal endothelium, good visualization. Rational consistent use of adhesive and cohesive components facilitates basic manipulations during phacoemulsification and IOL implantation. To do this, it is necessary to correctly use and select viscoelastic for a particular operation based on the number of endothelial cells.

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

BackgroundTo 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. MethodsThirty 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. ResultsThe 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. ConclusionNd: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.

Effects of fluorescein on corneal endothelial morphology after fundus fluorescein angiography in patients with diabetic macular edema

Purpose To evaluate the effects of fluorescein dye on corneal endothelial morphology (CEM) after fundus fluorescein angiography (FFA) in patients with diabetic macular edema (DME). Methods In this retrospective study, patients were divided into two groups, nonproliferative diabetic retinopathy (Group-1, NPDR) and proliferative diabetic retinopathy (Group-2, PDR). CEM properties including endothelial cell density (ECD), coefficient of variation of cell area (CV), average cell area (AVG), percentage of hexagonal cells (HEX), and central corneal thickness (CCT) were measured before FFA and at week 1 and month 1 after FFA were collected from patients’ charts. Results The study consisted of 48 patient’s 48 eyes in Group-1 and 50 patient’s 50 eyes in Group-2. In both groups, the mean ECD, CV, AVG, HEX, and CCT measurements at week 1 and month 1 after FFA did not differ statistically from the mean measurements before FFA (p > 0.05). The mean ECD measurements in Group-1 were higher than that in Group-2 and showed statistically significant differences among the groups (p < 0.01 for all). In the Pearson correlation analysis in Group-1, there was no statistically significant relationship between best-corrected visual acuity (BCVA) and (intraocular pressure) IOP values and ECD, AVG, CV, HEX, and CCT measurements (except central macular thickness [CMT] and HEX) before FFA, at week 1 and month 1 after FFA (p > 0.05). In Group-2 there was no statistically significant relationship between BCVA, IOP, and CMT measurements and ECD, AVG, CV, HEX, and CCT measurements before FFA, at week 1 and month 1 after FFA (p > 0.05). Conclusions There is no significant change in CEM after FFA in patients with NPDR and PDR with DME.

Evaluation of scleral thickness in patients with Fuchs endothelial dystrophy.

To evaluate scleral thickness using anterior segment-optical coherence tomography (AS-OCT) in Fuchs endothelial dystrophy (FED) and compare the results with healthy individuals. Thirty-two eyes of 32 patients with FED and 30 eyes of 30 age, gender, spherical equivalent and axial length matched healthy participants were included. All subjects underwent a detailed ophthalmological examination including endothelial cell density and central corneal thickness (CCT) measurements. Scleral thickness was measured by AS-OCT (Swept Source-OCT, Triton,Topcon,Japan) in 4 quadrants (superior, inferior, nasal, temporal) from 6mm posterior to the scleral spur. The mean ages were 62.5 ± 13.2 (33-81) for FED group; 64 ± 8.1 (48-81) for control group. CCT was significantly greater in FED group than in the control group (586.8 ± 33.1 (514-635) vs 545.0 ± 20.7 (503-587), respectively)(p = 0.000). In FED group, mean scleral thickness in the superior, inferior, nasal and temporal quadrants were 434.0 ± 30.6 (371-498), 442.8 ± 27.6 (395-502), 447.7 ± 31.4 (382-502), 443.4 ± 30.3 (386-504) μm, respectively. In control group, the mean scleral thickness in the superior, inferior, nasal and temporal quadrants were 381.3 ± 20.0 (341-436), 383.2 ± 16.0 (352-436), 389.2 ± 21.0 (353-440), 383.2 ± 19.2 (349-440) µm, respectively. The mean scleral thickness was significantly higher in all quadrants in FED group than in control group (p = 0.000). In patients with FED, scleral thickness was significantly higher. FED is a progressive corneal disease that results in the accumulation of extracellular material in the cornea. These findings suggest that the accumulation of extracellular deposits may not be limited to the cornea. Due to their functional similarity and anatomical proximity, sclera may also be affected in FED.

Effect of Nondominant Left-Handed Phacoemulsification Surgery on Corneal Endothelium.

To evaluate the effect of phacoemulsification surgery performed with the nondominant left hand on the corneal endothelium. The study included 160 patients who were followed up for at least six months after uneventful cataract surgery. Seventy-seven patients who underwent nondominant left-handed phacoemulsification were evaluated as Group 1 and 83patients who underwent dominant right-handed phacoemulsification were evaluated as Group 2. In all the patients, preoperative axial length (AL), aqueous depth (AD), anterior chamber depth (ACD), and lens thickness (LT) were evaluated. All phacoemulsification procedures were undertaken with the same device by two surgeons using the same technique, and the intraoperative cumulative dissipated energy (CDE) value, effective phacoemulsification time, and total operative time were recorded. Corneal endothelial cell density (ECD), coefficient of variation (CV) percentage, hexagonal cell percentage (HCP), and central corneal thickness (CCT) measurements were evaluated by specular microscopy preoperatively and at the postoperative first and sixth months. The two groups had a similar age and gender distribution and did not significantly differ in terms of the preoperative AL, AD, ACD, LT, intraoperative CDE, effective phacoemulsification time, and total operative time with similar age and gender distribution (p > 0.05 for all). The preoperative and postoperative first- and sixth-month specular microscopy measurements of ECD, CV, HCP, and CCT ​​were also similar in the groups (p > 0.05 for all). In this study, it was observed that nondominant left-handed phacoemulsification resulted in similar changes in endothelial cell count and morphology to those obtained from dominant-handed phacoemulsification.

Non-invasive endothelial cell density measurement of in toto pre-stripped DMEK-roll - impact of pre- and intraoperative endothelial cell loss on postoperative midterm clinical outcome.

To measure the endothelial cell density (ECD) of the in toto pre-stripped endothelial Descemet membrane lamellae (EDML) and to describe the impact of pre- and intraoperative endothelial cell loss (ECL) on postoperative midterm clinical outcome. The ECD of 56 Corneoscleral Donor Discs (CDD) was first measured with an inverted specular microscope (t0pre). The measurement was then repeated non-invasively after the preparation of the EDML (t0post). DMEK was performed the next day using these grafts. Follow-up examinations took place 6 weeks, 6 months and 1 year postoperatively where the ECD was assessed. In addition, the impact of ECL 1 (during preparation) and ECL 2 (during surgery) on the ECD, visual acuity (VA) and pachymetry at 6 months and 1 year was investigated. The average ECD (in cells/mm²) at time points t0pre, t0post, 6 weeks, 6 months & 1 year was 2584 ± 200, 2355 ± 207, 1366 ± 345, 1091 ± 564 and 939 ± 352. The average logMAR VA and pachymetry (in µm) was 0.50 ± 0.27 and 597 ± 63, 0.23 ± 0.17 and 535 ± 54, 0.16 ± 0.12 and 535 ± 54, 0.06 ± 0.08 and 512 ± 37, respectively The ECL 1 (9% on average) had no significant impact on the main outcome measures after 6 months and 1 year (p > 0.11). The ECL 2 correlated significantly with the ECD and the pachymetry at 1 year postop (p < 0.02). Our results indicate that the non-invasive ECD measurement of the prestripped EDML roll before its transplantation is feasible. Despite significantly decreasing ECD up to 6 months postoperatively, visual acuity further improved and thickness further decreased up to 1 year postoperatively.

The safety and efficacy of phacoemulsification surgery in uncomplicated cataracts with and without an ophthalmic-viscosurgical-device.

To compare and evaluate the results of phacoemulsification surgery involving and not involving an ophthalmic-viscosurgical-device (OVD). A prospective, randomized controlled trial included 60 eyes of 60 patients scheduled to receive phacoemulsification surgery. In order of presentation, patients were randomized into two groups to undergo different surgical techniques: the OVD-free group (n = 30) and the OVD group (n = 30). Each patient's operating time, total ultrasonography (U/S) time, cumulative dissipated energy (CDE), aspiration time, and volume of balanced salt solution (BSS) aspirated were recorded. At 1 day, 1 week, and 1 and 3 months postoperation, measurements of endothelial cell density (ECD) and intraocular pressure (IOP), were taken and compared between the groups. Total U/S time (p = .567) and CDE (p = .168) were similar between the groups. In the OVD group, operating time (p = .011), aspiration time (p < .001), and volume of BSS aspirated (p < .001) were greater than in the OVD-free group. The change in ECD between the groups was not statistically significant at all visits (p = .433, p = .147, p = .379, p = .534; respectively). Although IOP increased in the OVD group at 1 day postoperation (p = .001), no difference emerged between the groups at 3 months postoperation (p = .121). Phacoemulsification surgery without an OVD took less time than with the OVD and caused no significant loss in ECD. Surgeons concerned about elevated IOP following cataract surgery should apply the OVD-free method.

The effect of anterior segment parameters on surgical success of Descemet membrane endothelial keratoplasty: a prospective study.

To investigate how anterior segment parameters affect the success of Descemet membrane endothelial keratoplasty (DMEK) in patients with endothelial insufficiency without stromal opacities and to identify factors predisposing them to repeat keratoplasty. Our prospective observational study included patients who underwent primary DMEK for Fuchs' endothelial dystrophy and pseudophakic bullous keratopathy between March 2019 and March 2020. After a detailed ophthalmologic examination, corneal topographic analysis, anterior segment optical coherence tomography (AS-OCT) scans, endothelial cell density (ECD) and axial length (AL) measurements were performed. Surgical success was defined as no endothelial dysfunction during follow-up. Changes in the parameters and how preoperative parameters affect surgical success were investigated. In 43 eyes of 43 patients (mean age: 68.58 ± 8.51years), mean visual acuity was 1.73 ± 0.74 LogMAR before DMEK and 0.31 ± 0.29 LogMAR in the final visit. Central corneal thickness (CCT, p = 0.026) and mean anterior chamber depth (ACD, p = 0.001) affected surgical success. Preoperative CCT values greater than 770µm increased the risk of repeat keratoplasty by 8.75-fold, whereas preoperative ACD values less than 2.5mm increased the risk by 2.92-fold. Preoperative higher CCT and lower ACD values were associated with surgical failure after DMEK. Early surgery may be considered for more successful results. This prospective study has been registered on the ClinicalTrials.gov system with the registration number NCT04420429 on 06/06/2020.

Retardation of Myopia by Multifocal Soft Contact Lens and Orthokeratology: A 1-Year Randomized Clinical Trial.

This randomized, single-blind, clinical trial compared the effectiveness of multifocal soft contact lenses (MFSCLs), orthokeratology contact lenses (Ortho-kCLs), and single vision spectacles (SVSs) for myopia control. Sixty-six eligible Chinese subjects, aged 7 to 15 years old with cycloplegic refraction measurements between -1.00 and -8.00 diopters (D), astigmatism not more than 1.00 D, and no history of myopia control treatment, were randomly assigned to wear MFSCLs, Ortho-kCLs, or SVSs for 1 year. For all three groups, baseline measurements of cycloplegic refraction, axial length (AL), and corneal endothelial cell density (CECD) were made. At the 6- and 12-month follow-up visits, changes in cycloplegic refraction, AL, and CECD were measured in the MFSCL and SVS groups. For the Ortho-kCL group, only changes in the AL were measured at 6 and 12 months, and CECD was measured at the 12-month follow-up visit. After 1 year of lens wear, myopia progression of the SVS group, -0.938±0.117 D, was greater than that of the MFSCLs group, -0.591±0.106 D (P=0.032). Thus, MFSCLs reduced the rate of myopia progression by 37.0% compared with the SVSs. The AL elongations after 1 year were 0.30±0.03 mm for MFSCLs (P=0.027 vs SVSs), 0.31±0.04 mm for Ortho-kCLs (P=0.049 vs SVSs), and 0.41±0.04 mm for SVSs. Compared with the SVS group, the reduction in AL elongation was 26.8% and 24.4% in the MFSCL and Ortho-kCL groups, respectively. There were no significant differences in CECD among the three groups (P>0.05). Compared with SVSs, wearing MFSCLs and Ortho-kCLs significantly delayed myopia progression. MFSCLs and Ortho-kCLs are safe and promising methods of myopia control (chictr.org number, ChiCTR2100048452).

Studying the changes of corneal endothelium cells in patients with spherical refractive errors

Objective: To study of the relationship between spherical refractive errors and the changes in corneal endothelial cells. Methods: This sectional study, 1098 eyes of 663 persons attending the ophthalmological clinic at Tishreen University Hospital were studied between the years 2020-2021, they were divided into three groups according to the spherical equivalent value (193 nearsighted, 254 partially sighted, 216 long sighted), and also each was divided into three groups according to the value of the spherical equivalent. From the farsightedness and myopia groups to groups according to the severity of the refraction present (mild, moderate, severe), all participants underwent a complete ophthalmological examination including corneal endothelial cell counts by Endothelium Mic. Non contact, Specular Microscope, where the average of three successive measurements of endothelial cell density (MCD), coefficient of variation (CV) for cell volume, and hexogram (EX%) were taken. Results: The values of endothelial cell density (MCD) (P ˂ 0.05) and hexameric cell percentage (EX%) (P ˂ 0.05) decreased statistically significantly, while the value of the covariance (CV) increased (P ˂ 0.05) with increasing myopia, This change was at the expense of moderate myopia and severe myopia, while mild myopia did not have a statistically significant effect, as well as for hyperopia, where we did not find significant statistical differences in the three variables (MCD) (EX%) (CV) (P ˃ 0.05). Conclusion: Hyperopia does not affect the endothelial cells of the cornea, while moderate to severe myopia causes a significant change in the endothelial cells of the cornea.

Effect of Myopic Femtosecond Laser-Assisted LASIK on Anterior Chamber Inflammation (Flare Values) and Corneal Endothelium: A Prospective before and after Study.

Purpose This study aimed to investigate whether femtosecond laser-assisted LASIK (FS-LASIK) surgery causes inflammation in the anterior chamber and to analyze its effect on endothelial cells. Methods This prospective, longitudinal study included left eyes of 30 patients (19 females) who had undergone FS-LASIK surgery due to myopia and myopic astigmatism. Endothelial cell density (ECD) and morphological measurements were performed using a specular microscopy, and laser flare photometry was used to measure the anterior chamber flare values on the day of surgery. iFS™ Advanced FS and VISX STAR S4-IR Wavescan Excimer Laser platforms were used. Flare measurements were repeated on the postoperative 1st day and 7th day and the 1st and 3rd months. The endothelial measurements were repeated in the 3rd month. Results Preoperatively, the mean flare was 5.59 ± 1.24 photons/ms; it was 6.49 ± 2.42 on the postoperative 1st day, 5.87 ± 2.27 on the 7th day, 5.68 ± 1.66 on the 1st month, and 5.35 ± 1.24 on the 3rd month. A significant difference was observed only between the preoperative and postoperative 1st day flare values (p=0.047). The decrease in the ECD was clinically insignificant but statistically significant, with an average of 97.0 ± 209.9 cell count/mm2 (3.3%, p=0.017). However, there was no significant change in the coefficient of variation (p=0.448) and hexagonality (p=0.096). No significant correlation was found between the increase in the flare value on the postoperative 1st day and variables. A significant correlation was found between the decrease in ECD and the preoperative ECD (r = 0.356, p=0.027). Conclusion FS-LASIK caused minimal inflammation in the anterior chamber on only the 1st postoperative day; additionally, a minimal decrease of cell count with no morphological changes were noted in the endothelial cells on postoperative 3rd month. This trial is registered with NCT04899258.

Endothelial cell loss after accelerated corneal crosslinking using pachymetry-guided hypo-osmolar riboflavin dosing in thin keratoconic corneas.

To report the intraoperative changes in corneal pachymetry, as well as the efficacy and safety of accelerated corneal crosslinking (A-CXL) treatment using only hypo-osmolar riboflavin (HO-RF) solution in progressive keratoconus patients with thin corneas. University of Health Sciences, Prof. Dr. Cemil Tascioglu Education and Research Hospital, Istanbul, Turkey. Retrospective study. Thin keratoconic corneas (<400 m without epithelium) who had A-CXL (9 mW/cm2-10 minutes) with HO-RF solution application were enrolled in the study. Intraoperative corneal pachymetric changes and uncorrected and corrected distance visual acuities (UDVA and CDVA), refraction power values, topographic values, and endothelial cell density (ECD) measurements were recorded preoperatively and at 1st, 3rd, 6th, and 12th month follow-up postoperatively. 31 eyes of 25 patients (mean age: 24.17 ± 3.07 years) included in this study. The mean thickness increased to 438 μm (P = .001) after the application of HO-RF solution, and it was reduced to 424 μm (P = .001) after ultraviolet irradiation. At all postoperative visits after month 1, there was a significant increase in both UDVA (P < .05) and CDVA (P < .01) values and a significant decrease in both maximum keratometry (P < .05) and ECD (P < .01) values. Accelerated CXL with only HO-RF solution application throughout the procedure in thin corneas was effective but seemed to result in a significant ECD decrease postoperatively.