Central 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.

Changes in corneal endothelial cells after scleral-sutured fixation of intraocular lens in children with congenital ectopia lentis: a 2-year follow-up.

To investigate the changing patterns of corneal endothelial cells and the associated factors in children with congenital ectopia lentis (CEL) after scleral-sutured fixation of intraocular lens (SSFIOL). Zhongshan ophthalmic center, Guangzhou, China. Retrospective study. Patients were divided into the surgery group and the control group. Central endothelial cell density (ECD), coefficient of variation in cell size (CV), the percentage of hexagonal cells (hexagonality, HEX), average cell size (AVG) and central corneal thickness (CCT) were analyzed for both group at baseline and each follow-up visit. Clinic characteristic, ocular parameters, IOL decentration and IOL tilt of patients in the surgery group were collected. Multiple linear regression was performed to assess the potential associated factors for the postoperative changes in corneal endothelial cells in the surgery group. After 2-year follow-up, the decline of ECD was 17.8% (95%CI: -21.8 to -13.9) in the surgery group and -3.1% (95%CI: -5.2 to -1.0) in the control group(P<0.001), while the increase of AVG was 24.3%(17.1to 31.6) in the surgery group and 2.7%(1.0 to 4.5) in the control group (P<0.001). Multivariate analysis showed that AL≥24mm and WTW<12.2mm were significantly associated with greater loss of ECD (β=-241.41, 95% CI: -457.91 to -24.91, P=0.030 and β=251.63, 95% CI: 42.10 to 461.17,P=0.020, respectively) and AL≥ 24mm was significantly positively associated with the increase of AVG (β=34.81, 95% CI: 0.90 to 68.71, P=0.044). SSFIOL has a significant impact on corneal endothelium in children with CEL. More attention should be paid to monitor postoperative corneal endothelium change during long-term follow-up in CEL children, especially for those with longer AL and smaller WTW.

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.

Phacoemulsification versus Laser Peripheral Iridotomy for Treating Primary Angle Closure Glaucoma: A Systematic Review and Meta-Analysis.

Primary Angle Closure Glaucoma (PACG), is caused by narrowing the iridocorneal angle and increases the risk of blockage in the trabecular meshwork. Phacoemulsification and laser peripheral iridotomy (LPI) effectively control IOP elevation and widen the angle. This systematic review and meta-analysis compared Phacoemulsification and LPI Effectiveness for PACG. We searched Medline, Embase, and CENTRAL. We included randomized controlled trials (RCTs) that compared Phacoemulsification and LPI for individuals with PACG. We sought to evaluate the following outcomes: mean IOP, number of glaucoma medications, visual acuity (VA), visual field (VF) progression, peripheral anterior synechiae (PAS), Shaffer gonioscopy grading, central corneal thickness (CCT), central endothelial cell density (CECD), and poor response to surgery. The standardized mean difference (SMD) was used to represent continuous outcomes, while the risk ratio (RR) was used to represent dichotomous outcomes. 5 RCTs that enrolled 917 participants were deemed eligible. The phacoemulsification group showed statistically significance lower mean CCT and CECD and lower risk of poor response to surgery compared to LPI (SMD = -1.10; 95% -1.50, -0.70; P<0.001, SMD -366.12; 95% -652.59, -79.65; P=0.01, and RR 0.35; 95% 0.23, 0.54; P<0.001 respectively). There were no significant improvement in IOP and number of medications between both groups (SMD = -0.74; 95% CI = -2.26, 0.78; P=0.34, and SMD -17.58; 95% CI = -50.28, 15.12; P=0.29 respectively). Finally, there were also no significant differences in VA, VF progression, PAS, and mean Shaffer gonioscopy grading between both groups. Phacoemulsification showed statistically significant lower mean corneal thickness, central endothelial cell density, and lower risk of poor response to surgery compared to LPI. However, there were no significant differences in mean IOP, number of medications, VA, VF progression, PAS, and mean Shaffer gonioscopy grading between Phacoemulsification and LPI.

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.

Comparison of implantation of posterior chamber phakic IOL implantation and laser vision correction in terms of corneal endothelial cells: 3-year observational paired-eye study.

To compare the postoperative endothelial cell counts of EVO-implantable collamer lenses (ICLs) with a central hole (V4c and V5) and laser vision correction surgery (laser in situ keratomileusis or photorefractive keratectomy). B&VIIT Eye Center, Seoul, South Korea. Retrospective observational and paired contralateral study. 62 eyes of 31 patients who underwent EVO-ICLs with a central hole implantation in one eye (phakic intraocular lens [pIOL] group) and laser vision correction in the contralateral eye (LVC group) to correct refractive errors were retrospectively reviewed. Central endothelial cell density (ECD), percentage of hexagonal cells (HEX), coefficient of variation (CoV) in cell size, and adverse events were evaluated for at least 3 years. The endothelial cells were observed using a noncontact specular microscope. All surgeries were performed, without complications during the follow-up period. The mean ECD loss values compared with the preoperative measurements were 6.65% and 4.95% during the 3 years after pIOL and LVC, respectively. There was no significant difference in ECD loss compared with the preoperative values (paired t test, P = .188) between the 2 groups. No significant loss in ECD was observed at any timepoint. The pIOL group showed higher HEX ( P = .018) and lower CoV ( P = .006) values than the LVC group at the last visit. According to the authors' experience, the EVO-ICL with a central hole implantation was a safe and stable vision correction method. Moreover, it did not induce statistically significant changes in ECD at 3 years postoperatively compared with LVC. However, further long-term follow-up studies are required to confirm these results.

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.

Donor Endothelial Cell Density Not Changed Immediately After Ex Vivo Corneal Cross-Linking

Purpose: The aim of this study was to evaluate the effect of corneal cross-linking on central endothelial cell density (ECD) by comparing masked measurements before and immediately after preparation of cross-linked (CXL) and non–cross-linked (non-CXL) donor corneas. Methods: Thirty donor corneas were randomized 1:1 to either CXL or non-CXL using a modified Dresden protocol. Specular microscopic images of the central corneal endothelium were obtained within 36 hours of recovery and within 3 hours of preparation completion. Images were sent to a central cornea image analysis reading center for ECD determination in a masked, dual-graded manner. Results: Before and after preparation, the mean ECD was 2567 ± 305 cells/mm2 and 2525± 339 cells/mm2 for the CXL group (n =15) and 2652 ± 365 cells/mm2 and 2572 ± 513 cells/mm2 for the non-CXL group (n =15), respectively. The mean difference in ECD before and after preparation was not statistically significant for the CXL and non-CXL groups (P = 0.36; P = 0.31, respectively). In addition, an independent sample t test showed no statistically significant difference in the ECD change between the CXL and non-CXL groups (P = 0.67). Conclusions: Our specular microscopic findings show that ex vivo cross-linking of donor corneas does not seem to produce acute decrease of central endothelial cell density. These findings are encouraging and assist in warranting a clinical trial examining its value in reducing refractive errors and improving postoperative visual outcomes in eyes with keratoconus that undergo keratoplasty.

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.

Orthokeratology in adults and effect on quality of life

ObjectiveTo determine changes in various ocular parameters of adults wearing orthokeratology (ortho-k) lenses and their levels of satisfaction and quality of life (QoL) after commencing treatment. MethodsAdults aged 18–38 years, with mild to moderate myopia and astigmatism < 1.50D, were wearing ortho-k lenses for one year. Data collection, which included history taking, refraction, axial length (AL), corneal topography, corneal biomechanics, and biomicroscopy examination, was performed at baseline and every 6 months during the study period. The level of satisfaction with the treatment and QoL was determined via questionnaires. ResultsForty-four subjects completed the study. AL was shortened significantly at the 12-month visit: AL −0.03 (-0.45 to 0.13) mm compared to baseline (p < 0.05). A significant number of subjects in both groups presented with overall and central corneal staining, but the majority were mild (Grade 1). Central endothelial cell density was reduced by 40/mm2 (loss rate 1.4 %) (p < 0.05). High scores were obtained in the satisfaction questionnaire, with no significant differences between visits. At the 12-month visit, NEI-RQL-42 total score, dependence on correction, activity limitation, appearance, and satisfaction with the treatment all significantly increased compared to baseline values. ConclusionsResults suggest that ortho-k can be an effective and safe myopia correction technique for adults with low to moderate myopia, improving daytime vision without serious adverse events. Satisfaction with ortho-k lens wear was high, particularly those who were dependent on vision correction and found spectacles or contact lenses limiting specific activities or cosmetically undesirable.

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.

The effects of acute angle closure crisis on corneal endothelial cells in patients with type 2 diabetes mellitus.

ObjectiveThis study investigated the effects of acute angle closure crisis (AACC) on the corneal endothelial cells in patients with type 2 diabetes mellitus (DM) to identify the factors that cause corneal endothelial cell injury.MethodsWe examined 154 patients who visited Qingdao Eye Hospital for AACC in one eye (154 eyes; 28 men and 126 women; mean age of 68 ± 8 years). We divided the participants into non-DM, DM well-control, and DM poor-control groups, with the unaffected eyes used as controls. Each participant was evaluated at the hospital while under AACC. We measured the relevant index and corneal parameters of the participants for statistical analysis.ResultsThere were significant statistical differences in corneal parameters among the three groups. The decreased levels of central endothelial cell density (CD) and the percentage of hexagonal cells (6A) were statistically relevant among the groups (P<0.05). The AACC duration was correlated with CD loss rate among the groups (P<0.05). The DM duration was correlated with CD loss rate in the DM well-control group. Compared with the non-DM group, the level of 6A decreased more significantly in the DM group after AACC (P<0.05). The AACC duration in the DM well-control group was significantly shorter than in the non-DM and DM poor-control groups (P<0.001). The DM poor-control group showed significantly worse visual acuity when compared with the other groups (P<0.05).ConclusionsDM may impact the functional status of corneal endothelial cells. AACC can worsen the corneal endothelium damage in patients with DM. Blood glucose levels and the duration of intraocular hypertension are closely related to the severity of corneal endothelial injury.

The best choice for low and moderate myopia patients incapable for corneal refractive surgery: implantation of a posterior chamber phakic intraocular lens

PurposeThis study aims to evaluate the early clinical outcomes of central hole phakic posterior chamber intraocular lens(ICLV4c) implantation for low and moderate myopia correction.MethodsThis retrospective clinical study included 27 patients(47 eyes)who underwent ICLV4c implantation to correct myopia with spherical equivalent (SE) between − 1.75D and −6.0D. The uncorrected visual acuity (UCVA), intraocular pressure(IOP), central anterior chamber depth (ACD), vault, and endothelial cell density (ECD) were evaluated after surgery.ResultsAt one year follow-up, the postoperative UCVA of patients was higher than the preoperative CDVA and showed a stable trend. There was no significant difference in ECD (p > 0.05) one month after the surgery, the vault was 0.77 ± 0.32 mm, which decreased to 0.63 ± 0.26 mm after one year of surgery. Similarly, ACD was 3.24 ± 0.25 mm in the preoperative, which decreased significantly to 2.05 ± 0.39 mm at one month, while rose to 2.2 ± 0.39 mm at one year after surgery. There was no significant correlation between IOP and ACD and vault at one month and one year after surgery. The correlation coefficient between ACD and vault was found to be − 0.72 at one month after surgery, while the same −0.71 after one year. One patient developed visual fatigue, one with glare, and while no other complications were observed with the rest of the patients.ConclusionThe ICL implantation is a safe, effective and stable method to correct low and moderate myopia, and may be a good alternative for patients with low and moderate myopia who cannot undergo corneal refractive surgery.

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.