Evaluation of the corneal thickness and endothelial changes following uncomplicated phacoemulsification in diabetic and non-diabetic patients with pseudo-exfoliation syndrome by specular microscopy.

PURPOSE: To evaluate corneal endothelial cell changes following uncomplicated phacoemulsification in diabetic patients with PEX, compared with diabetic patients and non-diabetic patients with PEX. METHODS: This prospective, comparative, non-randomized cohort study included 61 eyes of 61 patients who were diagnosed as having senile cataract. Patients were divided into three groups: Group (1) included 19 eyes of patients with DM and PEX, group (2) included 22 eyes of diabetic patients, and group (3) included 20 eyes of patients with PEX. All included patients had uncomplicated phacoemulsification with IOL implantation. Patients were examined by non-contact specular microscopy (NIDEK, CEM-530, Japan), preoperatively and postoperatively at regular follow-up periods (one, three, and six months postoperatively) with analysis of the endothelial cell density, percentage of hexagonal cells, CV, and CCT. RESULTS: By the end of follow-up period, there was a statistically significant reduction in ECD and HEX with a significant increase in CV and CCT in group one (DM-PEX). In group two (DM), a statistically significant decrease in ECD and HEX with a significant increase in CCT was reported, while in group three (PEX), the only significant difference was found in the form of ECD reduction. CONCLUSION: Patients with DM and PEX had significant changes regarding ECD, CV, HEX, and CCT which were more pronounced than in patients with DM only or PEX only. More attention should be paid while operating on diabetic patients with PEX to save corneal endothelium and decrease postoperative complications. STUDY REGISTRATION NUMBER: The study was retrospectively registered (16 July 2021) on ClinicalTrials.gov (NCT04965168).

Macular microvascular changes in children with transfusion-dependent beta-thalassemia.

BACKGROUND: To investigate the effect of iron overload on macular perfusion among transfusion-dependent thalassemia (TDT) patients using optical coherence tomography angiography (OCTA) METHODS: The study is a prospective observational case-control study. It included 27 eyes from 27 children with transfusion-dependent ß-thalassemia and 25 eyes from 25 age-matched controls. All participants were evaluated clinically and with OCTA Avanti RTVue-XR system (Optovue) to assess macular microvascular changes, by measuring vessels density (VDs) and foveal avascular zone (FAZ) area, at both superficial and deep retinal plexuses and at choriocapillaris level. RESULTS: Foveal and parafoveal zones were significantly thinner among thalassemia patients, with significantly larger FAZ area at the level of both superficial and deep retinal plexuses when compared with control group. The thalassemia group showed significant lower values compared with the controls regarding whole-image, foveal, and parafoveal deep VD. There were significant negative correlations between serum ferritin and deep (whole image and parafoveal) VD (r = - 0.429, P = 0.026, and r = - 0.452, P = 0.018, respectively). Choriocapillaris VDs (whole image and foveal) showed significant negative correlations with serum ferritin levels (r = - 0.390, P = 0.044 and r = - 0.401, P = 0.038, respectively) CONCLUSIONS: Macular microvascular changes were detected by OCTA examination in patients with TDT, mostly due to iron overload effect, as we selected patients on iron-chelating agent with the least harmful effect on the retina. The most affected layer is the DCP. Changes at the deep layer could be used as a sensitive biomarker for early macular perfusion changes in those patients. TRIAL REGISTRATION: Study registration number is UMIN000042657, date of registration: 2020/12/04 (retrospectively registered).

Evaluation of ciliary body by ultrasound bio-microscopy after trans-scleral diode cyclo-photocoagulation in refractory glaucoma.

PURPOSE: To evaluate the morphological changes of the ciliary body after diode laser trans-scleral cyclo-photocoagulation using ultrasound bio-microscopy in refractory glaucoma. SETTINGS: This prospective, interventional, non-comparative, non-randomized, longitudinal study was performed on 40 eyes with refractory glaucoma, during the period between February 2016 and March 2018. METHODS: All patients were treated with single session diode laser trans-scleral cyclo-photocoagulation. The intraocular pressure was obtained over a period of 3 months after the operation and morphological changes of the ciliary body were observed using ultrasound bio-microscopy. RESULTS: Trans-scleral cyclo-photocoagulation has achieved a reasonable success in reducing intraocular pressure to less than 22 mm Hg without increasing the number of glaucoma medication. The overall success rate was 40%, as the intraocular pressure decreased from a baseline mean value of 54.70 ± 12.27 to 42.45 ± 9.85 mm Hg 1 week after operation, 33.50 ± 8.00 mm Hg after 1 month, and 25.60 ± 6.62 after 3 months of operation. Ultrasound bio-microscopy detected reduction in the length and width of ciliary processes in addition to the ciliary muscle thickness of the treated quadrants. Intraocular pressure was more correlated to the width of the ciliary processes. CONCLUSION: Trans-scleral cyclo-photocoagulation is a rapid and effective procedure in treatment of refractory glaucoma with intraocular pressure reduction. Ultrasound bio-microscopy is a promising twin tool for cyclo-destructive procedures to detect ciliary body changes and can be used as a guide for re-treatment procedures.

Accelerated Epithelium-Off Corneal Collagen Cross-Linking For Keratoconus: 12-Month Results.

PURPOSE: The main aim of the study was to report visual, refractive, topographic, and aberrometric results of accelerated CXL in patients with keratoconus who were followed for 12 months and to highlight the important parameters that can be used in follow-up. SETTINGS: It was a prospective interventional non-randomized case series study, in which 40 keratoconus eyes of 40 patients were studied in the period between April 2016 and July 2018. METHODS: All eyes were examined preoperatively and post-accelerated CXL to evaluate visual acuity, refractive state, keratometric values, keratoconus indices, and corneal higher order aberrations (HOAs). RESULTS: The mean age of the studied patients was 28.4 ± 8.6 years (18-37years). One year after cross-linking, 11.6% of the eyes gained two lines of the UCVA, 26.4% of the eyes gained one line, 49.8% showed no change, 7.1% lost one line, and 5.1% lost two lines. Postoperative  BCVA showed 13.7% of the eyes gained at least two lines, 32.5% gained one line, 49.9% had no change, and 3.9% lost one line. The keratometric values changed significantly after CXL; K1 decreased by a mean of 0.41D, K2 by 0.62D while Kmax by 1.57 D. The significant changes in keratoconus indices were in index of vertical asymmetry (IVA), index of surface variance (ISV), and keratoconus index (KI). Vertical coma, spherical aberrations, and trefoil decreased significantly at 12 months compared to baseline values (p = 0.04, 0.017, 0.025, respectively). CONCLUSION: Keratoconus indices especially ISV, IVA, and KI along with HOAsparticularly vertical coma, spherical aberrations, and trefoil can add value beside keratometric readings in the follow-up of eyes treated with accelerated CXL.

Keratoconus Screening Among Myopic Children.

AIM: To assess the topographic corneal changes and the incidence of keratoconus among children with high myopia. SETTINGS: It is a prospective study, in which 174 eyes of children with high myopia were studied in the period between August 2015 and June 2018. METHODS: All patients were examined to assess the refractive error and corneal examination using Scheimpflug camera to evaluate different corneal parameters. RESULTS: Studied children aged between 6 and 14 years (11.05±1.98). Males represented 54% of the cases (n=94). The mean spherical error was -7.75±2.97 ranging from -6 to -13.50D. The mean cylindrical error was -4.12±1.78D (-1 to -8). Regarding corneal examination, data recorded were those about maximum K reading (kmax), thinnest location, highest anterior and posterior elevation in 4mm zone, and higher-order corneal aberrations. Analysis of the obtained data revealed 16 eyes (9.2%) with keratoconus. These eyes were considered as a separate group and compared with the remaining eyes. There was significant difference in kmax (p= 0.03), anterior elevation, and posterior elevation (p=0.01 for both). Regarding myopia or astigmatism, there were no significant differences when compared with normal eyes. But high myopia with low astigmatism were found in five eyes of them (31.2%). The main statistically different aberrations were vertical coma (-2.04±0.99) (p=0.01) and spherical aberrations (-0.9±0.78) (p=0.02). Regarding gender, there were 11 eyes in boys (68.7%), and this was statistically significant (p=0.01). Vernal keratoconjunctivitis with frequent eye rubbing was found in 6 eyes (37.5%). CONCLUSION: Children with high myopia irrespective of the degree of astigmatism may have corneal abnormalities which are more pronounced in cases with vernal keratoconjunctivitis. Corneal examination should be performed for highly myopic children to detect any corneal abnormality and to treat it as early as possible.

Effect of bilberry extract on slowing high-myopia progression in children: 2-year follow-up study.

AIM: To evaluate the effect of oral Difrarel on progression of high myopia in children and to study myopia course after its discontinuation. METHODS: A total of 64 highly myopic children were enrolled in this study. Patients were divided into two equal groups: group 1 was administered Difrarel for 1 year and stopped its intake for another year, and group 2 (control) did not take Difrarel. Refraction and axial length of the right eye of every subject were measured every 6 months in both groups. RESULTS: Each group had 32 eyes of 32 patients. The mean age was 9.34±2.27 years in group 1 and 9.33±2.2 years in group 2. Mean refraction and axial length at the start of the study were -10.78±2.6 D and 23.7±1.2 mm, respectively, in group 1, and -10.5±2.55 D and 23.9±1.4 mm in group 2. Refraction and axial length measurements every 6 months revealed statistically significant lower numbers in group 1 than group 2 after 1 year. After discontinuation of the drug, the difference between both groups remained significant. CONCLUSION: Oral Difrarel slowed axial elongation and stopped myopia progression in children with high myopia. The drug effect was consistent after its discontinuation for 1 year.

Evaluation of Optic Nerve Head Parameters and Retinal Nerve Fiber Layer Thickness in Axial Myopia Using SD OCT.

INTRODUCTION: The purpose of this research was to study the effect of increased axial myopia, in non-glaucomatous eyes, and its correlation with ONH parameters, and RNFL thickness, using Cirrus HD 4000 SD-OCT. METHODS: The myopia group included 86 eyes of 86 patients, while the control group involved 92 eyes of 92 patients, attending the Ophthalmology Outpatient Clinic in Minia University Hospital, between November 2013 and March 2015. ONH parameters and peripapillary RNFL thickness measurement were evaluated by using SD-OCT, selecting the standard optic disc cube 200 × 200. RESULTS: The mean age of the myopia group was (36.55 ± 9.44), the mean spherical equivalent was (-12.70 ± 3.87 D), and the mean axial length was (27.88 ± 1.92 mm). The control group had mean age of (34.82 ± 8.87), mean spherical equivalent of -0.65 ± 0.41 D, and mean AL of (22.16 ± 0.82). A significant difference was reported between the two groups, regarding disc area (p = 0.01), rim area (p = 0.001), vertical C/D (p = 0.01), average C/D ratio (p = 0.001), average and temporal RNFL thickness (p = 0.0001, p = 0.001, respectively). CONCLUSION: A significant difference was found between highly myopic non-glaucomatous eyes and the control group, regarding ONH parameters and RNFL thickness as measured by SD-OCT. As OCT magnification adjusted ONH parameters were larger, global and the temporal RNEL were thicker in the myopia group, those magnification adjusted parameters helped in an accurate evaluation of ONH and RNFL in highly myopic eyes, in order to avoid misdiagnosis of glaucoma in such eyes.

Assessment of Posterior Segment Using Spectral Domain OCT in Highly Myopic Eyes.

PURPOSE: Spectral Domain Optical Coherence Tomography (SD-OCT) was used to evaluate retinal and vitreo-retinal changes that occur in highly myopic patients. METHODS: This prospective study included 472 eyes of 472 patients suffering from high myopia (> -6.00 D), between May 2012 and December 2015. All patients were examined, using Cirrus HD OCT (Zeiss Cirrus TM HD-OCT model 4000), to detect any retinal or vitreo-retinal interface abnormalities.All obtained data was analyzed using Statistical Package for the Social Sciences software version 17 (SPSS Inc, Chicago, IL, USA) and the paired two-sided t-test. Bivariate correlations were performed between different parameters using the Spearman correlation coefficient (r). RESULTS: Mean spherical equivalent (MSE) was -13.11± 4.35D. Mean axial length (AL) was 28.5±1.62 mm. Posterior vitreous detachment (PVD) was the most frequent OCT finding; representing 33.4% of the cases, 13.7% of them were associated with macular traction. A statistically significant positive correlation was found between AL and MTM, full thickness macular hole, PVD with traction, and dome shaped macula (r = 0.49 and P = 0.001, r = 0.422 and P = 0.0001, r = 0.25 and P = 0.03, r=0.475, P=0.001 respectively). CONCLUSION: OCT is a valuable tool in detecting retinal and vitreo-retinal interface abnormalities in highly myopic eyes, and it can be used for follow up of those patients to avoid advanced retinal damage.