Corneal endothelium, retinal nerve fiber layer, ganglion cell complex, and perimetry measurements in normal eyes and those with primary open-angle glaucoma.

Background: Corneal endothelial cell (CEC) loss in glaucoma can be attributed to the direct compressive effect of elevated intraocular pressure. Herein, we aimed to evaluate specular microscopic changes in CEC count and morphology in correlation to retinal nerve fiber layer (RNFL) changes detected by spectral-domain optical coherence tomography (SD-OCT) in early and advanced primary open-angle glaucoma (POAG). Methods: This descriptive-analytical study involved patients with medically controlled POAG versus non-glaucomatous patients of the same age group. Specular microscopy, visual field testing, and SD-OCT of the RNFL and macular ganglion cell complex (GCC) were performed. Eyes with POAG were further subcategorized into early and advanced stages. Results: The study included 130 eyes of 130 participants; 70 were eyes with POAG (40 eyes with early-stage POAG, 30 eyes with advanced-stage POAG), and 60 were healthy eyes. The groups were comparable regarding mean age and sex. No significant difference was found in corneal parameters between healthy eyes, eyes with early POAG, and eyes with advanced POAG (all P > 0.05). In eyes with early-stage POAG, a significant negative correlation was found between the coefficient of variation (CV) and superior RNFL thickness (r = - 0.5; P = 0.018), and between the percentage of hexagonal cells (hexagonality) and vertical cup-to-disc ratio (r = - 0.43; P = 0.035). A significant positive correlation was found between hexagonality and superior as well as inferior RNFL thickness (r = + 0.53; P = 0.008 and r = + 0.50; P = 0.015, respectively). However, in the advanced glaucomatous eyes, no significant correlation was found between RNFL thickness and CEC parameters. Conclusions: CEC parameters were not affected in eyes with early or advanced POAG compared with healthy eyes, despite a significant thinning of RNFL and macular GCC. In eyes with early-stage POAG, a significant correlation was found between morphological characteristics of CECs, such as CV and hexagonality, with superior and inferior RNFL thickness in the optic nerve head on SD-OCT images. Future longitudinal studies with larger sample sizes are needed to verify our results.

Histopathology, matrix metalloproteinase-2 and alpha smooth muscle actin expression in Tenon's capsule of eyes with congenital glaucoma.

PURPOSE: To evaluate the ultrastructural features of collagen fibrils, matrix metalloproteinase (MMP) and alpha-smooth muscle actin (α-SMA) expression in the Tenon's capsule of buphthalmic eyes. METHODS: A prospective comparative case series study was conducted on 35 buphthalmic eyes vs 25 control eyes. Children with congenital glaucoma (CG) who underwent a combined trabeculectomy-trabeculotomy procedure with mitomycin C (CTTM); the Tenon's capsule was obtained during the surgical procedure. The control group included children with strabismus, the Tenon's capsule was obtained in the course of strabismus surgery. Both H&E and Masson's trichrome staining were done. The Metalloprotenease-2 (MMP-2), alpha smooth muscle actin (α-SMA) immunohistochemical staining was performed. RESULTS: Mean collagen percentage area by Masson trichrome stain in Tenons capsule was significantly higher in buphthalmic eyes (54.76% ± 0.32 vs 33.71% ± 1.4; P < 0.001).The percentage area of αSMA expression in Tenons capsule was significantly higher in buphthalmic eyes (4.93% ± 0.7 vs 2.00% ± 0.5; P < 0.001). However, MMP2 expression in Tenons capsule of the buphthalmic group was significantly lower than that of the control group (12.88% ± 2.95 vs 27.91% ± 0.2 respectively) P = 0.02. CONCLUSIONS: Tenon capsule of buphthalmic eyes have their own histopathological features and properties making them more liable for fibrosis with high rate of failure following antiglaucoma surgeries. Such detailed information has not been published before which may aid in the identification of new antifibrotic therapies in management of glaucoma.

Agreement between the newly developed OCT glaucoma staging system and the standardized visual field glaucoma staging system 2.

PURPOSE: The purpose of this research was to assess the agreement between the new optical coherence tomography (OCT) glaucoma staging system (GSS) and the visual field (VF) GSS 2 (GSS2). METHODS: This is a cross-sectional study of 161 eyes of 110 patients with controlled primary open-angle glaucoma (POAG). All eyes were subjected to VF examination using standard automated perimetry and Humphrey field analyzer II 750. GSS2 was used for the classification of the VF defects' severity. OCT of the optic disc and the macular ganglion cell complex (GCC) was performed using RTVue. Patients were classified by OCT GSS into six stages. RESULTS: The study examined 161 eyes of 110 patients with controlled POAG. The staging according to VF GSS2 was as follows: stage 0 (12.42%), border stage (12.42%), stage 1 (13.04%), stage 2 (14.29%), stage 3 (14.28%), stage 4 (14.28%), and stage 5 (19.25%). The staging by OCT GSS was as follows: stage 0 (18.6 %), border stage (17.3%), stage 1 (6.8%), stage 2 (9.31%), stage 3 (6%), stage 4 (11.8%), and stage 5 (30.43%). The sensitivity of the new OCT GSS was different in different stages of glaucoma. In this study, no normal control group was considered; thus, the specificity could not be calculated. There was moderate agreement between the two staging systems. CONCLUSIONS: OCT GSS is a reliable and objective method for diagnosing and monitoring glaucoma. Correlations were found between GSS2, inferior and total macular GCC thickness values, and cup-to-disc ratios, so considering these items as additional parameters may make this new classification even more sensitive than VF GSS2.

Hand-Held Nidek versus Table-Mounted Huvitz Autorefractors and Their Agreement with Subjective Refraction in Adults.

OBJECTIVE: To compare the agreement between commercially available table mounted and a hand-held autorefractors and their agreement with subjective refraction. The effect of different body position with the handheld autorefractometer was also evaluated. METHODS: A prospective study was performed on 253 healthy eyes. Refraction was acquired by a table-mounted Huvitz and hand-held Nidek autorefractometer, subjective refraction was acquired. Refractive errors were compared in terms of spherical equivalent (SE), cylinder power, and the J0 and J45. The level of agreement was evaluated by Bland-Altman plots. RESULTS: There was a significant difference in SE measurements between both devices and between them and subjective refraction (P=0.00). The Huvitz SE readings tended to be less myopic. However, limits of agreement (LOA) for SE were narrowest for Nidek sitting vs supine followed by Huvitz vs subjective SE refraction. The LOA for SE for Nidek sitting vs subjective SE were of wider range. For cylinder values, LOA were similar for all devices and positions and between them and subjective cylinder refraction. CONCLUSION: Table mounted Huvitz and Nidek portable autorefractor cannot be used interchangeably in clinical practice except for estimation of the cylinder power. No difference in refraction between sitting and supine positions for portable Nidek autorefractor but with caution in cylinder axis. High agreement was achieved between subjective refraction and Huvitz readings but not with Nidek hand-held autorefractor. A highly reliable spectacle prescription could be done based on Huvitz readings. Both devices and positions could be used interchangeably in estimation of K-readings.

Analysis of the Refractive Profile of Children with Oculocutaneous Albinism versus an Age-Matched Non-Albino Group.

PURPOSE: To find out and analyze the points of difference in the refractive profile between children with complete oculocutaneous albinism (OCA) and an age-matched, non-albino group seeking paediatric ophthalmic examination. METHODS: A cross-sectional study was conducted on 164 infants and young children in Paediatric Ophthalmology Center, Sohag City, Egypt. Informed consent was obtained from the participants' guardians. The study divided the population into 2 equal groups: albino group = 82 eyes, non-albino group = 82 eyes. Cycloplegic refraction and average keratometric measurements using the hand-held autokeratometer were taken for the study groups. RESULTS: In the albino group, astigmatism and hypermetropia were the most common refractive errors, 100% and 62% respectively, with significant difference between both groups. Mean total (TA), corneal (CA) and lenticular astigmatism (LA) were significantly higher in albino group (P<0.05). All albino eyes were high astigmats (≥1.25 D). CONCLUSION: This study is novel in being comparative and includes the largest sample size ever reported for albino eyes of infants and children. High WTR astigmatism is the most prevalent refractive error in albinos with an overall bias toward hyperopia, but extreme errors (>-11.00D myopia or >+10.00D hyperopia) are not common. Albino eyes have a significantly higher degree of LA which compensates for the high CA to decrease the amount of TA. The study emphasizes the importance of refraction examination and visual rehabilitation for OCA children as early as possible to reduce eye morbidity-associated low vision.

Common and rare complications following filtering surgery for children with congenital glaucoma; a5 years study.

PURPOSE: To determine the incidence of postoperative complications following combined trabeculotomy trabeculectomy with mitomycin C (CTTM) for congenital glaucoma (CG), in addition to documentation of some unusual complications and possible ways to manage these complications safely with minimal morbidity. METHODS: A retrospective observational study was performed on 190 eyes with CG had a CTTM procedure.Included eyes were operated upon between February 2015 and February 2020 in Sohag University Hospitals. Medical records were reviewed and postoperative complications were reported. Incidence of postoperative complications and their management were the main outcome measures. RESULTS: Early complications developed the form of shallow anterior chamber (AC) (16.3%), hyphema (10.5%), serous choroidal detachment (2%), hemorrhagic choroidal detachment (2%). Unusual and rare complications occurred in the form of iatrogenic Cushing syndrome, unilateral toxic keratopathy developed, vitreous hemorrhage (VH), intercalary staphyloma and decompression retinopathyLate complications included: high postoperative intraocular pressure (IOP) (16.5%), thin cystic blebs (13.1%), hypotony disc edema (2%), cataract (3.2%), one eye developed blebitis and one eye developed endophthalmitis. CONCLUSION: Surgical management of CG is full of complications in early and late postoperative periods such as shallow AC, hyphema and thin cystic blebs. Some unusual and rare complications developed such as iatrogenic Cushing syndrome, unilateral toxic keratopathy, vitreous hemorrhage, intercalary staphyloma and decompression retinopathy. If identified early; all these complications could be managed properly leading to a successful and favorable outcome.

Analysis of Bimatoprost-Induced changes on Rabbits eyelash Follicle: Clinical and Electron microscopic study.

OBJECTIVE: To analyze ultrastructural changes of rabbits' eyelash follicles treated with bimatoprost eye drops to increase our knowledge of how this drug works. METHODS: The study included 15 clinically healthy male rabbits. All rabbits were treated with bimatoprost 0.03% daily for 4 weeks with one drop of the topical eye drops applied to the conjunctival fornix of the right eyes; left eyes were used as controls. Eyelash lengths were measured before and after treatment. The eyelid of each animal was dissected for light and electron microscopic analysis. RESULTS: Both control and treated rabbit eyes matched regarding eyelash length before treatment (9.80±0.388mm vs 9.88±0.24mm) (P=0.108). There was a significant increase in eyelash length between control (9.75±0.33 mm) and treated rabbit eyes (11.60±0.46 mm) (P=0.369). Light and electron microscopy revealed, bimatoprost treated eyes had thick epidermis. The dermis contained two hairs growing out of the same hair follicle. Heavily keratinized Henle's layer, the cortical cells (Cx) have prominent nucleolus and cytoplasm is studded with melanin granules. CONCLUSION: Bimatoprost-induced eyelash changes were not restricted to increased eyelash length, thickness, and pigmentation but also showed increased number of eyelashes within the same hair follicle which were stronger and could resist pulling from the skin without any evidence of inflammatory cells within the specimens. These changes occurred as early as 1 month of treatment, giving rise to thoughts about the possibility of using bimatoprost eye drops as a prophylaxis against madarosis associated with chemotherapy if it is started 1 month before chemotherapy and continued afterwards, making eyelashes stronger and resistant to falling out.

Analysis of components of total astigmatism in infants and young children.

The aim of this study is to examine and analyze the contribution of corneal and lenticular components of total astigmatism (TA) in infants and young children and to determine whether there is any compensation for astigmatism by the lenticular component or not. The study was conducted on 614 eyes of 307 infants and young children. Cycloplegic refraction and keratometric measures using the Hand-held Autokeratometer (Nidek Co. Ltd., Hiroishi, Japan) were done for the study group under general anesthesia in Paediatric Ophthalmology Center, Sohag City, Egypt. We divided the sample into high astigmats (total cylinder ≥ 1.00 D; mean, 1.99 ± 0.89 D; n = 431 eyes; 70 %) and normal astigmats (total cylinder ≤ 0.75 D; mean, 0.55 ± 0.22 D; n = 183; 30 %). The prevalence of corneal astigmatism (CA) ≥ 1.00 D was (73 %), any degree of lenticular astigmatism (LA) was (85 %), (LA > 0.25 D = 72 %) TA was predominantly with the rule (n = 499 eyes, 81 %). Eyes with against the rule astigmatism were (n = 33 eyes, 5.3 %) and eyes with oblique astigmatism were (n = 82 eyes; 13.3 %). Gender or age differences in TA, CA, LA, or type of astigmatism were not significant. The prevalence of astigmatism found in this population of newlyborn infants and young children was relatively high, primarily corneal, and WTR astigmatism with high prevalence of oblique astigmatism. LA was much less than previous reports (mean = -0.0044 D), associated with more hyperopic eyes and eyes with high TA. The data suggest that a compensatory process exists between CA and LA to decrease the amount of TA.