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.

Corneal thickness and endothelial change after use of ocular hypotensive agents.

Corneal transplantation can restore visual function when visual impairment is caused by a corneal disease. However, this treatment is associated with the scarcity of cornea donors. The suitability of corneal donation from patients with glaucoma using ocular hypotensive agents (OHAs) is controversial. This study aimed to elucidate changes in corneal thickness, corneal endothelial cell density, and corneal endothelial cell hexagonality after OHA use in patients with primary open-angle glaucoma. We retrospectively reviewed the data of 53 glaucoma suspect eyes without OHA use and 106 primary open-angle glaucoma eyes under OHA use. All participants underwent corneal parameter assessment using SP-3000P (Topcon Corp., Tokyo, Japan) at the time of diagnosis and the final visit. The OHA dose and timing of use were recorded. The ocular hypotensive agents score (OHAS) was determined based on the number, formula, frequency, and duration of OHA use. Baseline data showed no significant differences between the two groups with and without OHA use. At the final visit, the OHA-treated group showed significantly lower corneal thickness and corneal endothelial cell density than those of the control group. A weak positive correlation between the OHAS and changes in corneal endothelial cell hexagonality was noted. However, no correlation was observed between the OHAS and changes in corneal thickness or endothelial cell density. In conclusion, patients with glaucoma and using OHAs should undergo the corneal structural properties examinations before donation to ensure the quality of donor cornea.

Clinical Observation of Posterior-Chamber Phakic Implantable Collamer Lens V4c Implantation in Myopic Patients with Shallow Anterior Chamber Depth: A Retrospective, Consecutive Observational Study

Purpose. The reference range for the preoperative anterior chamber angle width for ICL surgery is unclear. Our objective was to assess the clinical effect and the range of anterior chamber angle width of posterior-chamber implantable collamer lens V4c (ICL V4c) implantation in patients with anterior chamber depth (ACD) &lt; 2.8 mm. Methods. Patients who underwent ICL V4c implantation with shallow ACD were included in this retrospective study. The patients’ uncorrected and corrected distance visual acuity, angle of trabecular-iris (TIA), angle-opening distance (AOD500), trabecular-iris space area (TISA500), corneal endothelial cell density, vault, retinal nerve fiber layer thickness, intraocular pressure, visual field, and complications were analyzed. Results. Forty-one patients (68 eyes) completed at least 12 months of follow-up (median follow-up, 30 months). The effectiveness and safety indices were 1.09 ± 0.13 and 1.04 ± 0.21, respectively. The preoperative TIA values on the nasal and temporal sides were 39.78 ± 7.68 degree (range, 25.8-65.1 degree) and 41.54 ± 8.03 degree (range, 28.5-63.00 degree). Forty-seven eyes had uncorrected distance visual acuity ≥1.0, and 55 had corrected distance visual acuity ≥1.0 at the last follow-up visit. The TIA, AOD500, and TISA500 on the nasal and temporal sides were significantly reduced compared to those before surgery (all P&lt;0.01); no eye had an angle closure or elevated intraocular pressure. The ICL V4c vault was 290.88 ± 153.36 μm (range, 60.0-880.0 μm). No severe complications occurred in any patient. Conclusions. In patients with myopia with shallow ACD (2.55-2.79 mm), a preoperative TIA &gt;25.8° is safe and effective for a relatively long time after surgery; however, an extended long-term close follow-up is needed.

Intermediate-term impact on corneal endothelial cells and efficacy of Preserflo MicroShunt implantation in patients with open-angle glaucoma - a prospective study over two years.

Preserflo MicroShunt is a novel microinvasive bleb forming device for the treatment of primary open-angle glaucoma. The intermediate- and long-term success and the impact of this procedure on corneal endothelial cell density remain to be investigated. In this prospective observational study, 62 eyes of 55 glaucoma patients (mean age ± SD: 67.0 ± 15.0years) receiving a Preserflo MicroShunt were included. Corneal endothelial cell density, intraocular pressure and best corrected visual acuity were assessed preoperatively and at 3, 6, 9, 12, 18 and 24months postoperatively. Success rates, bleb revision rates and complications were analysed. Complete success was defined as an intraocular pressure reduction of ≥ 20% and achieving a target pressure of ≤ 18, ≤ 15 or ≤ 12mmHg without antiglaucoma medication. Qualified success indicated that the criteria were reached with or without medication. Corneal endothelial cells showed no significant decline over 24months (p > 0.05). Intraocular pressure showed a substantial reduction postoperatively (p < 0.001), decreasing from 29.6 ± 8,3mmHg to 13.0 ± 4.3mmHg after 24months (p < 0.001). Complete and qualified success with a target pressure ≤ 15mmHg was achieved in 52.9% and 54.6% of cases after 24months, respectively. Best corrected visual acuity did not change after 24months. Preserflo MicroShunt had no negative side effects on corneal endothelial cells and showed favourable success rates after 2years in patients with open-angle glaucoma.

Отдаленные результаты использования системы трехмерной визуализации в сравнении со стандартной аналоговой визуализацией в хирургии хрусталика

Abstract Long-term results of using a three-dimensional imaging system in comparison with standard analog imaging in lens surgery A.V. Zhuravlev, V.S. Stebnev, S.D. Stebnev, I.V. Malov, L.M. Nizamutdinova Samara State Medical University, Department of Eye Diseases, Department of Eye Diseases IPO, Samara, Russian Federation Eye Surgery LLC, Samara, Russian Federation Purpose. Assessment of the safety and effectiveness of lens surgery using three-dimensional visualization based on the analysis of long-term results of operations. Material and methods. The study involved 500 patients (500 eyes). The main group consisted of 250 patients with cataracts operated by phacoemulsification using the NGENUITY three-dimensional digital imaging system. The control group consisted of 250 patients using analog imaging, i.e. using standard eyepieces. Long-term results were evaluated 3, 6 and 12 months after surgery using parameters such as uncorrected and maximally corrected visual acuity, refractometry indicators and corneal endothelial cell density. Results. Although in the long-term period we did not record statistically significant differences between the achieved indicators of visual acuity, refractometry and density of corneal endothelial cells in the main and control groups, their average values were still slightly higher in the group of patients where three-dimensional digital imaging was used in the FEC process. Conclusion. The long-term results of a comparative study of visual acuity, endothelial cell density, spherical and cylindrical components of refraction when using analog and three-dimensional digital imaging in cataract surgery allow us to conclude that the latter method is still more effective than the standard one. All this, combined with great ergonomic capabilities, makes it possible to recommend three-dimensional digital visualization for wider dissemination in clinical practice. Key words:cataract surgery, three-dimensional digital visualization, standard analog visualization, visual acuity, refraction, density of endothelial cells

Clinical characteristics of viral-associated Fuchs uveitis syndrome and Posner-Schlossman syndrome in a Chinese population.

To identify the types of viral infection in aqueous humor (AqH) among patients diagnosed as Fuchs uveitis syndrome (FUS) or Posner-Schlossman syndrome (PSS) and investigate their relevance to clinical manifestations and visual outcome. A total of 375 patients and 171 patients were diagnosed as FUS or PSS in our department. AqH and serum samples from 68 FUS patients and 16 PSS patients were obtained during eye surgery. The viral etiologies, clinical features, auxiliary tests and visual prognosis of patients with FUS or PSS who underwent AqH analysis were analysed and compared. Among 68 FUS patients, rubella virus (RV), cytomegalovirus (CMV), herpes simplex virus (HSV) and varicella-zoster virus were identified in 17, 11, 1 and 1 patients, respectively. Seven patients with CMV and 1 with HSV were identified in 16 PSS patients. In both FUS and PSS groups, virus-associated eyes had higher proportion of secondary glaucoma and worse visual prognosis as compared with non-virus-associated eyes (all P < 0.05). In FUS group, specifically, CMV infection manifested as more obvious anterior segment inflammation and lower corneal endothelial cell density (CECD). RV infection showed a higher percentage of vitritis. In PSS group, CMV-associated PSS had a lower retinal nerve fiber layer thickness and CECD, worse visual prognosis as compared with non-virus-associated PSS (all P < 0.05). Our study identified 4 types of viral infection in FUS and 2 types of viral infection in PSS. Virus-associated patients are usually associated with more obvious clinical signs and poor visual prognosis.

Intraoperative Performance and Early Postoperative Outcomes Following Phacoemulsification With Three Fluidic Systems: A Randomized Trial.

To compare intraoperative performance and early postoperative outcomes following phacoemulsification with two systems using active fluidics and one using gravity-based fluidics. In this prospective randomized trial, 200 eyes were randomized to the traditional and Active Sentry groups (n = 80 eyes each) where the Centurion Vision System was used with traditional or Active Sentry (Alcon Laboratories, Inc) hand-pieces, respectively, or the Infinit group (n = 40 eyes) where the Infiniti Vision System (Alcon Laboratories, Inc) was used. Within the traditional and Active Sentry groups, there were two subgroups with low (30 mm Hg) or high (55 mm Hg) intraocular pressure (IOP) used. Outcome measures compared were: cumulative dissipated energy (CDE), percentage change in central corneal thickness (CCT) at 1 day, 1 week, and 1 month, anterior chamber cells at 1 day and 1 week, rate of rise and fall of IOP following occlusion break, corneal endothelial cell density (ECD), and macular thickness 6 months postoperatively. CDE was significantly lower in group II compared to the traditional group (2.96 ± 1.4 vs 4.14 ± 2.2, P = .001). With 30 mm Hg IOP, the Active Sentry group had significantly less percentage change in CCT at 1 week postoperatively compared to the traditional handpiece group (0.01% vs 0.02%, P = .008). Incidence of anterior chamber cells less than grade 2 on day 1 was significantly higher in the Active Sentry group (82.9% vs 52%, P = .03). Percentage change in ECD was significantly lower in the Active Sentry group (-0.957 vs -0.98%, P = .005). Significantly faster rise of IOP to baseline following occlusion break was seen in the Active Sentry group. The use of Active Sentry handpiece was associated with lower CDE, less postoperative increase in CCT, fewer anterior chamber cells, and faster rise of IOP following occlusion break. [J Refract Surg. 2024;40(5):e304-e312.].

Association between primary angle closure glaucoma and uric acid levels in serum and aqueous humor

PurposeTo evaluate abnormalities in serum and aqueous humor uric acid (UA) levels in primary angle closure glaucoma (PACG). MethodsPatients with PACG and age-similar and gender-similar controls (patients scheduled for cataract extraction) were enrolled prospectively. Serum UA levels were determined by enzymatic colorimetry; aqueous humor UA levels by Enzyme-Linked ImmunoSorbent Assay. A t-test was used to compare UA levels between PACG patients and controls, with one-way ANOVA used to compare levels across PACG subgroups with differing disease severity. Comparisons between PACG patients and controls were adjusted for systemic and ocular confounding factors using binary logistic regression. ResultsIn all, 131 PACG patients and 112 controls were included. The serum UA level was 266 ± 69 μmol/L in the PACG group and 269 ± 73 μmol/L in the control group (p = 0.71). The aqueous humor UA level was 35.4 ± 8.2 μmol/L in the PACG group and 53.9 ± 18.6 μmol/L in the control group (p < 0.001). This difference remained significant after adjusting for age, gender, systolic blood pressure, diastolic blood pressure, body mass index, axial length, central corneal thickness, anterior chamber depth, lens thickness, white-to-white distance, corneal endothelial cell density, and serum UA level (odds ratio: 0.88, 95 % confidence interval: 0.83–0.93, p < 0.001). ConclusionAqueous humor UA levels differ between PACG patients and controls, but serum UA levels do not. This indicates that local UA plays a role in the pathogenesis of PACG, but systemic UA does not.

Causes and outcomes of implantable collamer lens explantation in patients with corneal endothelial cell loss.

To investigate the correlated factors of corneal endothelial cell density (ECD) loss and ECD change in implantable collamer lens (ICL) explantation patients. Seoul St. Mary's Hospital, Seoul, South Korea. Retrospective analysis. The study cohort consisted of 93 eyes from 50 patients who underwent ICL explantation. Correlation analysis was performed to assess the ocular parameters associated with ECD loss, while percentage of ECD change (ΔECD%) was monitored up to 6 months postoperatively. Receiver operating characteristic (ROC) curve was used to set cutoff values of ocular parameters to prevent ECD loss after explantation. In multiple regression analysis, high vaulting, high vaulting/anterior chamber depth (ACD), low anterior chamber angle (ACA), and high iris pigmentations are the significant factors of ECD loss. At postoperative 6 months, 14 eyes (15.1%) had decrease (10.5% loss), 47 eyes (51.0%) were stationary, and 32 eyes (34.4%) had increase (12.7% gain) of ECD. The ROC curve analysis showed that vaulting had the highest area under the curve (AUC = 0.822), followed by vaulting/ACD (AUC = 0.821), ECD (AUC = 0.753), and ACA (AUC = 0.723) (all P < .01). Preoperative ECD showed a sensitivity of 77.6% and specificity of 86.7% in preventing ECD loss after explantation, with a cutoff value of 1722 cells/mm 2 , as determined by ROC curve analysis. Our study demonstrated that high vaulting is a significant factor in ECD loss among ICL-inserted patients. To prevent continuous ECD loss in ICL patients, close monitoring of ECD and making appropriate decisions regarding explantation may be necessary.

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.

Long-term dynamic changes and influencing factors of corneal morphology after multiple intravitreal injections of anti-VEGF drugs.

To observe alterations in corneal morphology caused by repeated intravitreal injections of anti-vascular endothelial growth factor (VEGF). Prospective cohort study. Seventy-seven eyes were treated with intravitreal injection of anti-VEGF from June 2021 to March 2023. There were 25 eyes of neovascular age-related macular degeneration (nAMD), 24 eyes of diabetic macular edema (DME), and 28 eyes of retinal vein occlusion (RVO). Aflibercept was used in 37 eyes and Ranibizumab was used in 40 eyes. 3 + PRN was used. Corneal endothelium and corneal thickness were measured using a corneal endothelial microscope. The data related to central corneal thickness, corneal endothelial cell density (ECD), average cell size, coefficient of variation (CV), proportion of hexagonal cells (Hex%) was collected. A comparison was also made between baseline and the dynamic changes of all indexes 1 year following the last injection. It was observed that in comparison to baseline, ECD and Hex% decreased significantly after the 3rd injection of Aflibercept and Ranibizumab. However, ECD did not decrease further and remained at the same level as after the last injection. Hex% and average cell size increased to a certain extent in comparison to the last injection. All the changes were found to be statistically significant (P < .01). After 3 injections, ECD in DME group was markedly lower than that in nAMD and RVO group, but the CV in DME group was higher than that in nAMD as well as RVO groups, and all the differences were statistically significant (P < .05). Following intravitreal anti-VEGF therapy, DME is more likely than other disorders to result in a decrease in ECD. Repeated intravitreal injections of anti-VEGF drugs can reduce the Hex% and ECD to a certain extent. After the last injection, Hex% can progressively recover, and ECD can remain stable without further declining. After injections, ECD in DME group was found to be significantly lower than that in nAMD and RVO groups, but CV in DME group was significantly higher in comparison to the other 2 groups. In patients with macular edema, repeated intravitreal injections of anti-VEGF may have certain effects on corneal morphology. Patients with diabetes mellitus in particular should pay special attention to corneal safety following repeated intravitreal injections if they have significantly reduced ECD at baseline.

Continuous Corneal Endothelial Damage by Chlorhexidine Alcohol Used for Disinfection in Nonophthalmic Surgery.

To report a case of corneal endothelial damage caused by alcohol-containing chlorhexidine gluconate (CG-A) and its progression over time. This was a case report. A 22-year-old man underwent neurosurgery under general anesthesia. CG-A (1%) was used for disinfection after the application of corneal protection tape. Postoperatively, the patient presented with hyperemia and swelling of the left conjunctiva and was referred to our department. Initial examination revealed left corneal epithelial erosion and corneal edema, which improved on postoperative day 14. The corneal endothelial cell density (ECD) was 3,345 cells/mm2 on day 14, decreased rapidly to 2,090 cells/mm2 on day 42, and slowly reduced to 1,122 cells/mm2 on day 168. Thereafter, no decrease in ECD was observed. CG formulations can lead to a persistent decrease in ECD over several months, even after improvement of acute corneal edema.

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.

Corneal endothelial cell density and associated factors among adults at a regional referral hospital in Uganda: a cross-sectional study.

To assess the prevalence of low corneal endothelial cell density and correlates of corneal endothelial cell density among adults attending Mbarara University and Referral Hospital Eye Centre in Uganda. In this hospital-based cross-sectional study, participants 18 years and older, were enrolled. We obtained informed consent, and basic demographic data. We also conducted visual acuity, a detailed slit lamp examination, intra-ocular pressure, corneal diameter, tear-film break-up time, keratometry, A-scan, and pachymetry on all participants. A confocal microscope Heidelberg HRT3 was used to examine the central cornea and to obtain the mean cell density (cells/mm2). To calculate the proportion of low endothelial cell density, descriptive statistics were used, whereas correlates of endothelial cell density were assessed, using linear regression analyses. We evaluated a total of 798 eyes of 404 participants aged between 18 and 90 years (males = 187, females = 217). The average endothelial cell density was 2763.6 cells/mm2, and there was a decrease in endothelial cell density with increasing age, irrespective of gender. There was no significant difference in endothelial cell density between males and females. Increasing age (adjusted coefficient - 10.1, p < 0.001), history of smoking (adjusted coefficient - 439.6, p = 0.004), history of ocular surgery (adjusted coefficient - 168.0, p = 0.023), having dry eye (adjusted coefficient - 136.0, p = 0.051), and having arcus senilis (adjusted coefficient - 132.0, p = 0.08), were correlated with lower endothelial cell density. However, increasing corneal diameter (adjusted coefficient 134.0, p = 0.006), increasing central corneal thickness (adjusted coefficient 1.2, p = 0.058), and increasing axial length (adjusted coefficient 65.8, p = 0.026), were correlated with higher endothelial cell density. We found five eyes (0.63%) from different participants with a low endothelial cell density (< 1000cells/mm2). Our study established baseline normal ranges of ECD in a predominantly black African population, and found that low ECD is rare in our population. The elderly, smokers, and those with past ocular surgery are the most vulnerable. The low prevalence could be due to a lack of reference values for the black African population.

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.

Enhanced Surgical Safety through Protective Penetrating Keratoplasty: A Retrospective Analysis of 22 Cases.

To assess the surgical safety, postoperative outcomes, and the impact of PPK on corneal endothelial cell density through a retrospective analysis of 22 cases. Settings and Design. A retrospective cross-sectional observational study was executed at Hermanos Ameijeiras Hospital from February 2018 to December 2021, involving 22 patients (22 eyes) who were unresponsive to other medical treatments and had a corrected distance visual acuity of ≤0.1. Patients underwent PPK, with surgical procedures and postoperative care documented. Statistical analysis was performed on qualitative and quantitative variables to evaluate the surgical outcomes and the corneal endothelial cell density changes postoperation. All surgeries demonstrated a significant improvement in postoperative visual acuity (p ≤ 0.001) and recorded a 9.2% decrease in the corneal endothelial cell density at 12 months. Noteworthy complications included one case of intraoperatively discovered haptic dislocation and one postoperative bacterial keratitis. PPK could potentially mitigate perioperative complications, ensure graft clarity, and reduce corneal endothelial cell loss, presenting itself as a viable alternative to traditional PK. Although the results are encouraging, larger-scale studies are essential to validate the benefits and applicability of PPK in broader clinical settings.

A Shape Memory Polymeric Shield for Protecting Corneal Endothelium During Phacoemulsification.

The purpose of this study was to explore the protective effect of a shape memory polymeric shield on corneal endothelium during phacoemulsification in rabbits. Poly-(glycerol dodecanedioate) (PGD) with a transition temperature of 24.416°C was prepared to make a shape memory shield with a thickness of 100µm, an arc length of 14 mm, and a radius of curvature of 8.8 mm. In the control group, a phaco-tip with bevel-down was used to simulate injury to the corneal endothelium by phacoemulsification in rabbits. In the experimental group, the pre-cooled and curled shape memory shield was injected into and removed from the anterior chamber before and after phaco-power release. Anterior segment optical coherence tomography (AS-OCT), confocal microscope, trypan blue/alizarin red staining, and scanning electron microscope were performed to measure endothelial damage after surgery. One day postoperatively, the lost cell ratio of the control group and the experimental group were 28.08 ± 5.21% and 3.50 ± 1.43%, respectively (P < 0.0001), the damaged cell ratios were 11.83 ± 2.30% and 2.55 ± 0.52%, respectively (P < 0.0001), and the central corneal thicknesses (CCT) were 406.75 ± 16.74µm and 340. 5 ±13.48µm, respectively (P < 0.0001). Seven days postoperatively, the endothelial cell density (ECD) of the control group and the experimental group were 1674 ± 285/mm2 and 2561 ± 554/mm2, respectively (P < 0.05). The above differences were all statistically significant. This PGD based shape memory shield has a protective effect on corneal endothelium during phacoemulsification. It reduces postoperative corneal edema and ECD decrease in the short term after surgery. The shape memory PGD "shield" in this study may have a use in certain human patients with vulnerable corneas of low endothelial cell count or shallow anterior chambers.

Evaluation of the results of contact lens assisted corneal cross-linking treatment in keratoconus patients with thin corneas.

We aimed to compare the efficacy and safety of accelerated contact lens-assisted cross-linking (CA-CXL) with Lotrafilcon B and Comfilcon A lenses in keratoconus (KC) patients with thin corneas. Retrospective, single-center study. We retrospectively included 51 eyes of 39 KC patients with corneal thickness <400µm after epithelial scraping (Epi-off), who underwent accelerated CA-CXL treatment with Lotrafilcon B (n=20) and Comfilcon A (n=31). Uncorrected and corrected distance visual acuity (UDVA and CDVA), manifest refraction values, corneal topographic data and endothelial cell density were recorded at preoperative and postoperative 1st, 3rd and 6th month controls. CDVA in the Comfilcon A group was higher than CDVA before surgery at 6 months postoperatively (p<0.001). When the two lenses were compared, CDVA was found to be significantly higher in the Lotrafilcon B group in the preoperative, postoperative 1st month and 3rd month values, but there was no significant difference between the postoperative 6th month values (p=0.028, p=0.018, p=0.044, p=0.181, respectively). The maximum keratometry (Kmax) value at the 6th month after surgery in the Comfilcon A group was significantly lower than in the Lotrafilcon B group (p=0,009). There was no significant difference between the endothelial cell density values between the groups (p=0.623, p=0.609, p=0.794, p=0.458, respectively). There was no significant difference between the progression, regression, and stability rates of the two groups (p=0.714). Accelerated CA-CXL with Lotrafilcon B and Comfilcon A silicone hydrogel lenses is a safe and effective method to stop progression in patients with thin corneas.

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.

Repositioned versus exchanged flanged intraocular lens fixation for intraocular lens dislocation

This study aimed to compare the outcomes of flanged intraocular lens (IOL) fixation with new IOL exchange after dislocated IOL removal and repositioned dislocated IOL in patients with IOL dislocation. Eighty-nine eyes that underwent flanged IOL fixation were retrospectively included, with 51 eyes in the exchanged IOL group and 38 eyes in the repositioned IOL group. In both groups, best-corrected visual acuity (BCVA) improved at 1, 3, 6, and 12 months postoperatively and did not differ between the two groups at any of these time points. However, at 1 week postoperatively, BCVA in the repositioned IOL group improved compared with baseline, whereas that in the exchanged IOL group did not. Moreover, there were lesser changes in the corneal endothelial cell density (ECD) and corneal astigmatism in the repositioned IOL group than in the exchanged IOL group. The IOL positions, including IOL tilt and IOL decentration, were not different between the groups. Flanged IOL fixation with new IOL exchange and with repositioned dislocated IOL for patients with IOL dislocation had similar visual outcomes and IOL position. However, the latter had a smaller corneal ECD decrease and astigmatic change. This technique was effective in treating IOL dislocation while minimizing corneal injury.