Changes In Central Corneal Thickness Research Articles

A Comparison of Functional Endothelial Changes between Phacoemulsification with PCIOL and Manual Small Incision Cataract Surgery with PCIOL

Intraocular surgery e.g., cataract surgery with PCIOL implantation is one of the leading causes of corneal endothelial injury and change in the functionality of the cornea. This observational study was conducted in the Department of Ophthalmology of Combined Military Hospital (CMH), Dhaka Cantonment, Dhaka, Bangladesh, between January and July of 2016, to assess and compare functional changes in cornea (i.e., endothelial thickness) after phacoemulsification with posterior chamber intraocular lens (PCIOL) implantation and manual small incision cataract surgery (MSICS) with PCIOL implantation. A total of 80 patients of age-related cataract were randomly selected based on inclusion and exclusion criteria. All patients underwent complete ophthalmic evaluation pre- and post-operatively (at day 1, after 1 week and 3 months) specifically for observation of the endothelial changes in cornea. Specular microscopy was done to assess corneal endothelial change. The mean central corneal thickness was increased at day 1 (564.71±22.45μ vs. 555.10±40.57μ), after 1 week (539.43±22.16μ vs. 535.08±38.87μ) and 3 months (523.49±21.29μ vs. 520.05±33.68μ) after phacoemulsification and MSICS from their preoperative value (508.72±23.96μ vs. 503.62±32.06μ) respectively. However, the differences were not statistically significant between two groups (P>0.05). The mean percentage of central corneal thickness change at day1, after 1 week and after 3 months following cataract surgery were found 11.01±6.30% and 10.22±26.54% at day 1, 6.04±7.52% and 6.25±21.24% after 1 week, 2.90±11.14% and 3.26±5.05% after 3 months in phacoemulsification and MSICS cases respectively. However, no statistically significant difference was observed in percentage of central corneal thickness change of both groups (P>0.05). To summarize, an increased central corneal thickness was observed after phacoemulsification and SICS from their preoperative values. Mugda Med Coll J. 2024; 7(1): 14-18

Corneal Endothelial Morphology and Ocular Biometric Indexes in Premature Children With and Without Retinopathy of Prematurity.

The purpose of this study was to analyze human corneal endothelial cells (HCECs) morphology and ocular biometrics in premature (PM) children with or without retinopathy of prematurity (ROP). Retrospective data on patient demographics, HCECs status, and ocular biometrics with at least 2 visits between 2016 and 2021 were reviewed. The main outcomes were endothelial cell density (ECD), coefficient of variation (CV), hexagonal cell ratio (HEX), central corneal thickness (CCT), axial length, anterior chamber depth, keratometry, corneal diameter, pupil diameter, and refraction status. Generalized estimating equation was used to evaluate the differences between PM no-ROP and ROP groups. We also analyzed the trend of ECD, CV, HEX, and CCT change with age between groups. The study included 173 PM patients without ROP and 139 patients with ROP. A total of 666 and 544 measurements were recorded in the PM no-ROP and ROP groups, respectively. The ROP group had higher spherical power, myopic spherical equivalent (SE), and steeper steep keratometry (K; P < 0.05). The ROP group had higher CV (P = 0.0144), lower HEX (P = 0.0012) and thicker CCT (P = 0.0035). In the HCECs parameters, the ROP group had slower ECD decrement (P < 0.0001), faster CV decrement (P = 0.0060), and faster HEX increment (P = 0.0001). A difference in corneal morphology changes between the ROP and PM no-ROP groups were prominent in patients with lower gestational age (GA) in the subgroup analysis. Worse HCECs morphology and higher myopic status were initially observed in patients with prior ROP but not in PM patients with no-ROP. ECD and HCECs morphology improved with age, especially in patients with low GA.

Comparison of clinical outcomes between femtosecond laser-assisted cataract surgery versus conventional phacoemulsification in vitrectomized eyes - A prospective interventional study.

To compare the clinical outcomes and surgical safety between femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification cataract surgery (CPCS) in vitrectomized eyes. A prospective interventional comparative study was conducted at a tertiary eye care center. Sixty consecutive cases requiring cataract surgery following pars plana vitrectomy were allocated into Group 1 (n = 30), who underwent FLACS with intraocular lens implantation, and Group 2 (n = 30), who underwent CPCS with intraocular lens implantation, and followed up for 3 months. Primary outcome measures were intraoperative ultrasonic cumulative dissipated energy (CDE) and intraoperative and postoperative complications. The secondary outcome measures were postoperative changes in endothelial cell count (ECC) and central corneal thickness (CCT). Baseline corrected distance visual acuity (CDVA), ECC, and CCT were comparable. Intraoperative CDE was significantly less in the FLACS group (8.11 vs. 15.83 percentage seconds; P = 0.012) with no intraoperative complication in either group. The postoperative CDVA was comparable between the groups with a trend toward earlier visual recovery in the FLACS group. The postoperative day (POD) 1 endothelial cell loss was higher in the CPCS group (7.54% vs. 2.05%), with the mean endothelial cell density being significantly higher in the FLACS group throughout the follow-up period (P < 0.05). POD-1 corneal edema was higher in the CPCS group compared to FLACS with no significant difference on follow-up. Intraoperative migration of silicone oil to the anterior chamber was observed in 40% versus 0% in the CPCS versus FLACS groups, respectively. FLACS can be safely performed in post-vitrectomy eyes with lesser intraoperative ultrasonic energy used, postoperative endothelial cell loss, and change in CCT compared to CPCS.

Prospective Randomized Clinical Trial Evaluating Efficacy and Safety of A New Ophthalmic Viscosurgical Device In Patients Undergoing Cataract Surgery.

To evaluate the efficacy and safety of Bio-Hyalur LVD compared to Viscoat® ophthalmic viscosurgical device (OVD) in patients undergoing routine cataract surgery. Two tertiary eye care hospitals in Italy. Prospective randomized clinical trial. This study compared the outcomes of Bio-Hyalur LVD versus Viscoat® ophthalmic viscosurgical device in patients undergoing standard cataract surgery with phacoemulsification and intraocular lens implantation from January 2021 to April 2022. The primary outcome was mean change in IOP at 6 hours. Secondary outcomes included 1-, 7-, 30- and 90-day mean intraocular pressure (IOP), 7-, 30- and 90-day best corrected visual acuity, endothelial cell density (ECD), change in central corneal thickness (CCT) and complications including intraocular inflammation. A total of 84 eyes of 84 patients (n = 41 in the Bio-Hyalur LVD group and n = 43 in the Viscoat group) were screened, enrolled, randomized, and included in the analysis. Mean change in IOP was significantly higher in the Viscoat group than in the Bio-Hyalur LVD group 6 hours (p = 0.034), 7 days (p < 0.001), 30 days (p < 0.001) and 90 days (p = 0.003) postoperatively. Mean change in UDVA and CDVA was significantly higher in the Bio-Hyalur LVD group 30 and 90 after surgery. No significant differences in ECD, CCT and complication rates were observed between groups at any time point. Bio-Hyalur LVD OVD is safe and effective for use in patients undergoing routine cataract surgery. Bio-Hyalur LVD OVD did not confer a higher risk of postoperative increase in IOP.

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.].

Effect of Age and Parity on Physiological Changes in the Eye During Pregnancy: A Prospective Longitudinal Study.

The hormonal and metabolic changes that occur during uncomplicated pregnancy affect the eye. The effects of maternal age and parity on the physiological eye changes in pregnancy have been scarcely documented. To determine these effects on some physiological eye changes that occur in pregnancy. A longitudinal study involving consecutively recruited 140 pregnant women aged 18-48 years attending antenatal clinic at the University of Nigeria Teaching Hospital, Enugu. A structured questionnaire was administered to consenting women, after which the Schirmer test, tear break-up time (tBUT), corneal sensitivity, central corneal thickness (CCT), and intraocular pressure (IOP) was measured in the second and third trimesters, and six weeks after delivery. The mean CCT showed a significantly greater increase among the multiparous (≥para 2) women in both the second and third trimesters compared with the primigravida/primiparous women (P = 0.032 and 0.049, respectively). There was no difference in mean CCT between the two parity groups at six weeks postpartum. Women aged 18-35 years showed a significantly greater increase in the mean CCT in the second trimester compared to those aged less than 35 years (P = 0.04). However, there was no difference in the mean CCT between the different age groups in the third trimester and at six weeks postpartum. The age and parity of women affect their level of CCT changes in pregnancy. Consideration of this effect may guide clinicians on their approaches to eye care and treatment during pregnancy.

Corneal Endothelial Cells and Central Corneal Thickness in Pseudoexfoliation Patients

Objective: Investigating the impact of pseudoexfoliation syndrome on changes occurring in corneal endothelial cells and central corneal thickness, while assessing the influence of the degree of pseudoexfoliation on endothelial cell changes. Methods: In this analytic case-control study (Cross Sectional), the research sample included 60 patients (120 eyes) from the ophthalmic clinic attendees at Tishreen University Hospital in Latakia during the period 2023-2024. Results: The average corneal endothelial cell count was lower in the pseudoexfoliation group (2218.91±311.5 cells/mm²) compared to the control group (2559.82±290.7 cells/mm²) with a (p-value of 0.0001). The average percentage of hexagonal cells was lower in the pseudoexfoliation group (48.55±14.9 %) compared to the control group (62.32±9.7%) with a (p-value of 0.0001). No statistically significant differences were observed between the research groups in terms of average cell volume change coefficient with a (p-value of 0.9). The average cell area was higher in the pseudoexfoliation group (487.92±71.3 µm²) compared to the control group (419.94±72.2 µm²) with a (p-value of 0.003). The average central corneal thickness was lower in the pseudoexfoliation group (515.93±41.9 µm) compared to the control group (544.22±26.6 µm) with a (p-value of 0.04). We observed increased changes in corneal endothelial cells and central corneal thickness with an increase in the degree of pseudoexfoliation. Conclusion: Corneal endothelial cells and central corneal thickness are affected in patients with pseudoexfoliation syndrome, and these changes increase with severity of pseudoexfoliation.

A New Biomechanical Deformation Response Parameter: Change in Central Corneal Thickness During Air Puff Induced Corneal Deformation

Purpose To investigate the percent change in central corneal thickness (%ΔCCT) during air-puff-induced deformation as an indicator of corneal biomechanical response. Methods Forty ex vivo human eyes from forty donors were imaged using the CorVis ST at experimentally controlled intraocular pressure (IOP) of 10, 20, 30, and 40 mmHg, followed by uniaxial strip testing to calculate tensile modulus. The CorVis ST research software tracked the anterior and posterior cornea edges and determined the dynamic corneal response (DCR) parameters. Eyes were excluded if image quality or posterior tracking issues were present. Custom algorithms were used to calculate CCT during deformation using a ray-tracing method to correct for Scheimpflug and optical distortion within each image. Correlation and stepwise regression analyses between the shape-related DCR parameters and %ΔCCT were conducted. A mixed model analysis was performed to test the effect of IOP and the strongest significant predictors of the stepwise regression on %ΔCCT. The significance threshold was set to p < 0.05. Results Thirty eyes were ultimately analyzed and CCT increased significantly from the pre-deformation state to the highest concavity state at each IOP level (p < 0.001). IOP and multiple shape DCRs were found to be significantly related to %ΔCCT (p < 0.0001). The strongest predictor of %ΔCCT was integrated inverse radius (IIR) (p < 0.0001; partial R2 = 0.4772) with no other parameter having a partial R2 value greater than 0.04. The mixed model analysis showed that IIR was the sole predictor (p = 0.0098) and IOP was no longer significant as a single predictor. However, the interaction of IIR with IOP (p = 0.0023) had a significant effect on %ΔCCT. Conclusion Percent change in CCT is influenced by corneal stiffness as indicated by the significant relationship with IIR. The %ΔCCT may be a potential biomarker for determining differences in corneal deformation response with corneal diseases.

Correlation between HbA1C and CCT in T2DM

Abstract An observational cohort study of central corneal thickness (CCT) in type 2 diabetes mellitus (T2DM) patients in hyperglycemic and euglycemic states. Context: To assess the significance of glycemic control in CCT measurement. Aims: The main aim was to assess the change in CCT with the change in glycemic state by following them after 3 months. Settings and Design: This study was carried out in the department of ophthalmology, SMVMCH, Pondicherry. Materials and Methods: This is an observational cohort study carried out at Sri Manakula Vinayagar Medical College and Hospital after obtaining ethics committee clearance. Fifty-six T2DM patients with HbA1C &gt;7 were included in this study with informed consent. Clinical history with complete ophthalmic examination done, CCT was measured using ultrasonic pachymetry (UP) along with blood samples to measure their blood sugars and HbA1C values. They were advised to follow up on the treatment given by the medical department. Patients were reviewed after 3 months to measure the CCT and blood sugar values. Statistical Analysis: Done using STATA software 16.0. Continuous data and categorical data were assessed using paired t-test and Chi-square test, respectively. Normality of data using Shapiro–Wilk normality test. Statistical significance was adopted with P &lt; 0.05. Results: In our study, the initial mean HbA1C was 9.4 ± 1.9 and mean CCT was 552.6 ± 40.6 μm, whereas follow-up mean HbA1C was 7.1 ± 1.2 and mean CCT was 548.5 ± 38 μm which shows statistical significance. Conclusion: Diabetics present with thicker corneas and there is a decrease in thickness once glycemic control has been achieved. Keeping this in mind, we suggest assessment of CCT in all diabetic patients during clinical work-up.

Effect of Dorzolamide-Timolol fixed dose combination on central Corneal Thickness in patients of Primary Open Angle Glaucoma Versus Normal Tension Glaucoma

PURPOSE: To evaluate the effect of dorzolamide/timolol fixed dose combination on central corneal thickness in primary open-angle and normal tension glaucoma. METHOD: This retrospective cohort study was approved by the Ethical Review Board of College of Ophthalmology and Allied vision Sciences (1469/23) and was conducted at Diagnostic clinic Mayo Hospital, Lahore from March, 2023 to September, 2023. Sample size was calculated by a formula whose level of significance (????) was 5%, standard deviation (????) 30.9 and test values of population mean (µ̥) was 540. Using non-probability convenient sampling method total sample size was 80 patients of age group 30 to 60 which divided into normal tension and primary open angle glaucoma of 40 each. Patients with corneal edema, diabetes, and allergic to dorzolamide-timolol fixed dose combination were excluded. Data was analyzed using SPSS version 25.00. Wilcoxon signed ranks test and chi-square test were used for the significance of the study. Data p-value &lt;0.005 considered significant. All the tests were performed after patient’s informed consent. Intraocular pressure (IOP) and central corneal thickness (CCT) were measured by Goldmann applanation tonometer and ultrasound Pachymeter respectively. RESULTS: IOP and CCT in right eye 16.17± 7.05 (p=0.000) and 545.50± 22.2 (p=0.098) respectively and of left eye 16.56± 7.00 (p=0.003) and 549.16± 20.0 (p=0.133) respectively. This illustrates significant difference in intraocular pressure after treatment in both eyes but insignificance difference in central corneal thickness. CONCLUSION: Dorzolamide-Timolol combination successfully reduces IOP as intended and leads to no statistically significant change in central corneal thickness.

Central Corneal Thickness and Endothelial Cell Changes in Diabetics and Age-Matched Non-diabetics in a Tertiary Care Hospital in Central India.

Background Diabetes has become an epidemic, significantly impacting ocular health as one of its end-organ responses. Among the various ocular complications, alterations in corneal morphology stand out. Central corneal thickness (CCT) and endothelial cell function are vital parameters in assessing intraocular pressure, conducting pre-refractive surgery evaluations, and maintaining corneal transparency. Understanding these changes in diabetic individuals compared to non-diabetics is crucial for managing ocular health in this population. Aim and objective This study evaluates and compares CCT and endothelial cell changes between diabetic individuals and age-matched non-diabetics. By analyzing these parameters, the study seeks to provide insights into the impact of diabetes on corneal morphology and its implications for ocular health. Methods The study recruited 124 patients from the Ophthalmology Outpatient Department (OPD) at Acharya Vinoba Bhave Rural Hospital (AVBRH), Sawangi. A cross-sectional research design was employed to collect data over six months. Patients were carefully selected, and informed consent was obtained from all participants. CCT and endothelial cell parameters were assessed using specular microscopy, a non-invasive imaging technique. Statistical analysis was done using the software Statistical Package for the Social Sciences (SPSS) for inferential statistics, such as t-tests and ANOVA, and comparing parameters between diabetic and non-diabetic groups.Findings were interpreted based on both statistical significance and clinical relevance. Results In diabetic patients, the mean CCT was 547.91 µm, while it was 523.62 µm in non-diabetic individuals.The T statistic for this variable was 5.14, indicating a17 significant differencebetween the two groups. Similarly, significant differences were found between diabetics and non-diabetics for endothelial cell density, coefficient of variation, and hexagonality, as evidenced by their respective T statistics of 7.46, 5.17, and 4.91. Endothelial cell density averaged 2375 cells/mm2 in diabetics and 2666.95 cells/mm2 in non-diabetics. Additionally, the coefficient of variation was higher among people with diabetes (40.87%) compared to non-diabetics (35.09%). Hexagonality, a measure of endothelial cell shape, was lower in diabetic corneas (40.48%) than in non-diabetic corneas (46.46%). Conclusion The study observed significant differences in corneal morphology, including central thickness and endothelial cell changes, between diabetic and non-diabetic individuals. These findings underscore the impact of diabetes on ocular health and emphasize the importance of monitoring corneal parameters in diabetic patients. Understanding these changes can aid in better management and treatment strategies for ocular complications associated with diabetes.

Effects of graft detachment on the central corneal thickness after uncomplicated Descemet membrane endothelial keratoplasty.

To determine if early central corneal thickness (CCT) and best-corrected visual acuity (BCVA) changes indicate graft detachment after uncomplicated Descemet membrane endothelial keratoplasty (DMEK). In this analysis of our prospectively collected ADDA registry data ( https://drks.de/search/de/trial/DRKS00027180 ), 45 pseudophakic eyes underwent DMEK surgery at the Department of Ophthalmology, RWTH Aachen University. Anterior segment optical coherence tomography (AS-OCT), the presence of stromal ripples on the posterior corneal surface, and BCVA measurements were assessed prior to, 1day, 1week, 1month, and 6months after surgery. Eyes were categorized into three groups: no graft detachment (group 1) (20/45; 44.4%), < 1/3 graft detachment (group 2) (14/45; 31.1%), ≥ 1/3 graft detachment followed by rebubbling (group 3) (11/45; 24.4%). Eyes in group 3 had a greater CCT prior to (746.8 ± 95.8µm vs. 665.0 ± 74.4µm, P = 0.041), and 1week (666.8 ± 119.5µm vs. 556.5 ± 56.8µm, P = 0.001) after DMEK compared to group 1. By 1month, CCT in all groups aligned. Comparing prior to and 1week after DMEK, none of the eyes in group 1 had an increase in CCT, while the CCT increased in 25.0% of eyes in group 2 and 22.2% in group 3. In group 1, 90.0% had a CCT of < 600µm 1week after DMEK, compared to only 50.0% in group 2 and 36.4% in group 3. In group 1, 90.0% (18/20) had an improved BCVA 1week after DMEK, while in groups 2 and 3, 86.7% (12/14) and 18.2% (2/11) improved, respectively. One patient in group 3 showed posterior stromal ripples 1day and 1week after DMEK. If 1week after uncomplicated DMEK CCT is < 600µm and has decreased from before surgery, BCVA has improved, and there are no posterior stromal ripples, a graft detachment ≥ 1/3 and the need for rebubbling are very unlikely. In all other cases, meticulous slit-lamp and OCT inspection of the peripheral graft for detachments should be advised.

Effect of corneal cross-linking on biomechanical changes following transepithelial photorefractive keratectomy and femtosecond laser-assisted LASIK.

Purpose: To evaluate the change in corneal biomechanics in patients with postoperative ectasia risk when combining two common laser vision correction procedures (tPRK and FS-LASIK) with cross-linking (in tPRK Xtra and FS-LASIK Xtra). Methods: The study included 143 eyes of 143 myopic, astigmatic patients that were divided into non-cross-linked refractive surgery groups (non-Xtra groups, tPRK and FS-LASIK) and cross-linked groups (Xtra groups, tPRK Xtra and FS-LASIK Xtra) according to an ectasia risk scoring system. The eyes were subjected to measurements including the stress-strain index (SSI), the stiffness parameter at first applanation (SP-A1), the integrated inverse radius (IIR), the deformation amplitude at apex (DA), and the ratio of deformation amplitude between apex and 2mm from apex (DARatio2mm). The measurements were taken preoperatively and at 1, 3, and 6months postoperatively (pos1m, pos3m, and pos6m). Posterior demarcation line depth from the endothelium (PDLD) and from the ablation surface (DLA) were recorded at pos1m. Results: SP-A1 significantly decreased, while IIR, deformation amplitude, and DARatio2mm increased significantly postoperatively in all four groups (p < 0.01)-all denoting stiffness decreases. In the FS-LASIK group, the changes in IIR, DA, and DARatio2mm were 32.7 ± 15.1%, 12.9 ± 7.1%, and 27.2 ± 12.0% respectively, which were significantly higher (p < 0.05) compared to 20.1 ± 12.8%, 6.4 ± 8.2%, and 19.7 ± 10.4% in the FS-LASIK Xtra group. In the tPRK group, the change in IIR was 27.3 ± 15.5%, significantly larger than 16.9 ± 13.4% in the tPRK Xtra group. The changes of SSI were minimal in the tPRK (-1.5 ± 21.7%, p = 1.000), tPRK Xtra (8.4 ± 17.9%, p = 0.053), and FS-LASIK Xtra (5.6 ± 12.7%, p = 0.634) groups, but was significant in the FS-LASIK group (-12.1 ± 7.9%, p < 0.01). After correcting for baseline biomechanical metrics, preoperative bIOP and the change in central corneal thickness (△CCT) from pre to pos6m, the changes in the IIR in both FS-LASIK and tPRK groups, as well as DA, DARatio2mm and SSI in the FS-LASIK group remained statistically greater than their corresponding Xtra groups (all p < 0.05). Most importantly, after correcting for these covariates, the changes in DARatio2mm in the FS-LASIK Xtra became statistically smaller than in the tPRK Xtra (p = 0.017). Conclusion: The statistical analysis results indicate that tPRK Xtra and FS-LASIK Xtra effectively reduced the biomechanical losses caused by refractive surgery (tPRK and FS-LASIK). The decrease in corneal overall stiffness was greater in FS-LASIK than in tPRK, and the biomechanical enhancement of CXL was also higher following LASIK than after tPRK.

Nuclear Grades based on Lens Opacities Classification System III associated with Phacoemulsification Parameters and Postoperative Central Corneal Thickness

Abstract&#x0D; Introduction &amp; Objectives : To determine association of nuclear cataract grades based on Lens Opacities Classification System (LOCS) III with phacoemulsification parameters and postoperative Central Corneal Thickness (CCT) and visual acuity.&#x0D; Methods : This was a prospective observational study in patient with uncomplicated senile cataract who gave consent and underwent phacoemulsification. Institutional Ethics Committee clearance was taken for the study. Preoperative nuclear cataract was evaluated using Lens Opacities Classification System (LOCS) III. Only nuclear grading NO and NC was obtained. All procedures was performed using peristaltic phaco machine and in the bag IOL implantation. Phacoemulsification parameters (US Total Time and CDE) were noted and compared in different grades of cataract. CCT change was recorded at day one after surgery.&#x0D; Results : Forty-six patients were evaluated. The mean USTT was 120.85 (56-252) seconds, mean CDE was 21.10 (5.70 – 43.38), and mean CCT change after surgery was 81.54(27 – 240). Nuclear grading of LOCS also had linear correlation with US Total Time (NO p&lt;0.001, r=0.734; NC p&lt;0.001, r=0.790) and CDE (NO p&lt;0.001, r=0.728; NC p&lt;0.001, r=0.685). There was significant correlation between CCT change with postoperative VA (p=0.002, r=0.443) and CDE (p&lt;0.001, r= 0.553). CCT change also correlate with nuclear opacity (p=0.012, r=0.367) and nuclear color (p=0.035, r=0.312).&#x0D; Conclusion : Nuclear grading of LOCS III related to the amount of time and energy used in phacoemulsification, and also CCT change after surgery as a qualitative measurement of corneal edema. Increasing postoperative CCT affected patient's visual acuity after cataract surgery.

Corneal tomography changes following major (6 mm) medial rectus muscle recession: a prospective cohort study using Pentacam®

ABSTRACT Introduction The aim of this study is to evaluate changes in corneal astigmatism, axial anterior corneal curvature, as well as changes in the anterior chamber depth and central corneal thickness, 2 months following the unilateral recession of medial rectus muscle in children. Methods Thirty-three children with esotropia were prospectively evaluated following unilateral medial rectus muscle recession, using Pentacam®. Comparisons were made between the operated and fellow unoperated eyes, pre, and postoperatively. The assessment was made for changes in the radius of axial curvature on major meridians at 3 and 3.5 mm from the optical corneal center in the mid-peripheral zone. Astigmatism changes of the anterior and posterior corneal surface were calculated using vector analysis software (astigMATIC®). ANOVA model was used to examine the interaction between age or central corneal thickness and postoperative changes in anterior and posterior surface corneal astigmatism. Results In the intervention group, changes in anterior and posterior corneal surface astigmatism were statistically significant, with a mean increase of 0.59Dx92 and 0.08Dx91, respectively. In the mid-peripheral corneal zone, there is an increase in the radius of anterior corneal axial curvature more evident nasally 3.5 mm from the corneal center on the horizontal meridian, with corresponding decrease superiorly and inferiorly at 3 and 3.5 mm from the corneal center on the vertical meridian. Discussion The changes in total astigmatism of the operated eyes are mainly attributed to the anterior corneal surface. These changes are associated with flattening in the 180 meridian of the cornea, leading to a shift to “with-the-rule” astigmatism.

Evaluation of Intraocular Pressure in Eyes After Femtolasik Surgery

Introduction: Femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) surgery is a surgical procedure performed in the treatment of refractive errors. Given the changes in central corneal thickness, intraocular pressure may be lower and underestimated, which may lead to a late diagnosis of ocular hypertension/glaucoma. Aims: The aim of this study was to evaluate and compare intraocular pressure, by different methods, before and after FS-LASIK, for correction of myopia or myopic astigmatism. Methods: Retrospective and observational study, which included eyes undergoing FS-LASIK surgery (November 2020 to November 2022). The intraocular pressure values were measured (preoperatively, on the 1st, 3rd and 6th postoperative month) using contact tonometry (Goldmann applanation tonometry) and non-contact tonometry (by Corvis®ST according to the formulas: pachymetry – Ehlers, Shah, Dresden, Spoerl – and biomechanics – corrected and uncorrected). The intraocular pressure values obtained at 6 months with the different methods were compared with the Goldmann applanation tonometry intraocular pressure values obtained at baseline. Results: Ninety patients (of a total of 174 eyes) underwent FS-LASIK, with a preoperative spherical equivalent of -3.7±1.7. Preoperatively (mean ± standard deviation) Goldmann applanation tonometry was 15.0±1.9 mmHg; the intraocular pressure values obtained through the Corvis® ST (in mmHg) according pachymetry: Ehlers (13.5±2.6), Shah (14.3±2.3), Dresden (14.5±2.2) and Spoerl (14.5±2.1); and biomechanics: corrected (14.4±1.9) and not corrected (15.3±2.1), respectively. At 6 months postoperatively, all showed statistically significant differences, with the exception of Shah's formula (p=0.074); comparing the preoperative Goldmann applanation tonometry with each of the formulas at the end of the follow-up, the Ehlers formula did not present statistically significant differences (p=0.434), the Shah formula a value of p=0.047 and the others a value of p&lt;0.001. Conclusion: Femtosecond laser-assisted laser in situ keratomileusis surgery underestimates intraocular pressure measurement by contact tonometry. In non-contact tonometry, at 6-month follow-up, the Shah formula appears to be less influenced by this bias. More studies are needed to evaluate the best method to assess I intraocular pressure measurement after FS-LASIK surgery.

A Multicentric Cross-Sectional Observational Study to Analyze the Effects of Moderate High Altitude on Ocular Health.

Prolonged exposure to hypoxia at high altitudes can affect the eyes through various mechanisms, culminating in reduced vision. Multiple studies on this subject have focused on the ocular effects of high altitude on intraocular pressure (IOP), corneal thickness, and the retina. However, there is a lack of literature on the effects of 'moderate high altitude (2000-3000 m)' on the eyes. Hence, we designed our study to determine the impact of moderate high altitude on the eyes. We recruited two age and gender-matched groups of 250 research participants, each at moderate high altitude (Group A) and plains (Group B), respectively, to determine the effects of moderate high altitude on ocular health, if any. We found a statistically significant increase in dry eye in Group A. We also found four cases of central serous retinopathy and one case of central retinal vein occlusion in Group A. There was no statistically significant change in visual acuity, IOP, or central corneal thickness. There is a vast lacuna in the literature on this particular altitude range, and further studies are required to confirm our findings. It is also recommended that lubricant eye drops be advised as a standard prophylactic measure for all individuals traveling and staying at moderate high altitude.

Changes in Central Corneal Thickness, Corrected Intraocular Pressure, and Iridocorneal Angle in Unilateral Acute Anterior Uveitis.

The release of inflammatory mediators in the anterior chamber can lead to the structural alteration of the corneal and uveal tissue. To compare the changes in Central Corneal Thickness (CCT), corrected Intraocular Pressure (cIOP) and Iridocorneal Angle (ICA) in unilateral acute anterior uveitis (AAU) before and after treatment. The study was a hospital based comparative study conducted between July 2018 to June 2019. Newly diagnosed, untreated unilateral Acute Anterior Uveitis (AAU) adult cases above 16 years were included in the study. Ethical clearance was obtained from the Institutional Review Committee of Institute of Medicine. Eighty-two unilateral AAU cases (Total 164 eyes including 82 unaffected were analyzed) underwent Goldmann applanation tonometry (GAT) and corneal topography at presentation and three weeks after treatment. The cIOP was calculated by the Ehlers formula. The mean CCT of affected eyes was greater (563.84±51.49μm) compared to unaffected eyes (535.99±31.48μm) before treatment (p=0.001) and was reduced (533.2±25.71μm) after treatment (p=0.01). There was no significant difference in IOP, cIOP, and ICA between the affected eyes (14.45±6.89mmHg, 13.14±7.14mmHg and 48.78±7.94°) and the unaffected eyes (14.02±2.36mmHg, 14.4±3.09mmHg, and 49.80°±8.21°) before treatment. There was no difference in IOP (14.04±2.76mmHg) and ICA (49.21°±6.72°) after treatment, however, there was a significant increase (p=0.01) in the cIOP (14.95±2.93mmHg). In the study, CCT of affected eyes was greater compared to unaffected eyes and reduced after treatment. There was no difference in cIOP and ICA in case eyes compared to control before treatment. However, cIOP increased after treatment.

Changes in Central Corneal Thickness and Central Macular Thickness following Uncomplicated Small-incision Cataract Surgery.

Cataract surgery is an invasive procedure that causes mechanical and inflammatory insult to the eye. The objective was to study the changes in central corneal thickness (CCT) which is an indirect indicator of corneal endothelial dysfunction and the changes in macular thickness following uncomplicated small incision cataract surgery (SICS) Materials and methods: This was a prospective observational study with a before-and-after design conducted in Reiyukai Eiko Masunaga eye hospital, Banepa, Kavrepalanchok, Nepal. SICS was performed on 68 eyes of 62 patients. Change in CCT and central macular thickness (CMT) from baseline was observed post-surgery on the first day, one week, and six weeks. There were 27 (43.5%) females and 35 males (56.5%) in the study. Mean age was 58.26 ±10 years. This difference of visual acuity between pre and post-operative state was statistically significant. The first post-operative day (POD) and first week post-operative CCT values when compared with preoperative CCT values were statistically significant. However, post-operative CCT values at six weeks were similar to preoperative values. Also, the differences at day one, first week and six weeks post-operative CMT values when compared with preoperative CMT values were statistically significant. This study revealed that there is a significant rise in CCT after SICS which gradually tends to normalize at six weeks. Similarly there is a gradual rise in CMT after SICS persisting even at six weeks. These changes were subtle and there was a marked improvement of visual acuity at six weeks after SICS.

A study to determine the effect of hydroxychloroquine (HCQ) on central corneal thickness (CCT) in patients with rheumatoid arthritis (RA).

Corneal thinning is common in rheumatoid arthritis (RA), thereby affecting the central corneal thickness (CCT). Effect of hydroxychloroquine (HCQ) in RA has abounding literature on retinal toxicity, but there is lack of data on its corneal effects. A cross-sectional study was carried out to compare CCT in RA patients before treatment initiation (Group 1) with CCT in those on HCQ for ≥3 months (Group 2). Fifty patients were enrolled in each group. The mean age was 44.36 years with similar age, gender distribution and visual acuity in both groups. The mean CCT of patients in the cohort was 521.80 µm ± 32.57 µm and 523.94 µm ± 33.40 µm in the right eye (RE) and left eye (LE), respectively. Mean CCT in Group 1 was (RE) 522.80 µm/(LE) 524.26 µm and in Group 2 was (RE) 520.80 µm/(LE) 523.62 µm, and there was no significant difference in CCT between both the groups. Median duration of HCQ usage in Group 2 was 24 months, with the median cumulative dosage being 171 g and a majority having a dosage of 200 mg/day. There was no significant correlation between the duration/cumulative dosage of HCQ intake and CCT. No corneal deposits were identified in any patient. CCT of RA patients was similar to those reported in the Indian literature. However, there was no significant change in CCT or corneal deposits identified with an HCQ dosage of 200-400 mg/day. Longer follow-up would provide clarity on the impact of duration and cumulative dosage of HCQ on corneal changes and CCT.