Glaucoma Research Articles

Comparison of two formulas for calculating intraocular lens in patients with angle-closure glaucoma.

This study compares the accuracy of SRK/T and Barrett Universal II intraocular lens (IOL) measurement formulas for cataract phacoemulsification combined with intraocular lens implantation in angle-closure glaucoma (ACG) patients. Prospective serial case studies were conducted. A total of 146 patients (146 eyes) with ACG complicated with cataract who underwent cataract surgery with atrial angle closure ≤180° were observed. All the patients were divided into 2 groups according to different intraocular lens calculation formula, with 73 cases in each group (73 eyes). SRK/T intraocular lens calculation formula was used in group A, and Barrett intraocular lens calculation formula was used in group B. The visual acuity, the best corrected visual acuity, intraocular pressure and central anterior chamber depth were significantly improved in 146 eyes 3 months after operation, and the differences were statistically significant. There was statistically significant difference in postoperative spherical equivalent (SE) between the 2 groups (t = 2.147, P = .033), and there was statistically significant difference in preoperative expected refraction between group A and postoperative SE (t = 4.221, P < .001). There was no significant difference between preoperative expected diopter and postoperative SE in group B (t = 1.857, P = .065). The difference in absolute predicted error between the 2 groups was statistically significant (t = 4.929, P < .001). Axis length was negatively correlated with SRK/T formula and Barrett Universal II formula absolute refractive error value (ME) (group A: r = -0.740, P < .001; group B: r = -0.532, P < .001), there was A significant negative correlation between absolute refractive error value and anterior chamber depth in both groups (group A: r = -0.382, P = .001; group B: r = -0.358, P = .002). The cataract phacoemulsification combined with intraocular lens implantation is safe and effective for ACG patients with cataract. For such patients, the Barrett Universal II intraocular lens measurement formula may be more accurate after surgery.

The Development and Validation of a Glaucoma Health Score for Glaucoma Screening Based on Clinical Parameters and Optical Coherence Tomography Metrics

Background/Objectives: This study aims to develop and validate a Glaucoma Health Score (GHS) that incorporates multiple individual glaucoma risk factors to enhance glaucoma detection in screening environments. Methods: The GHS was developed using a retrospective dataset from two clinical sites, including both eyes of glaucoma patients and controls. The model incorporated age, central corneal thickness, intraocular pressure, pattern standard deviation from a visual field threshold 24-2 test, and two parameters from an optical coherence tomography (OCT) test: the average circumpapillary retinal nerve fiber layer thickness and the minimum thickness of the six sectors of the macular ganglion cell plus the inner plexiform layer. The GHS was then validated in two independent datasets: one from primary care sites using Maestro OCT data (test dataset 1) and another from an academic center using DRI OCT Triton (test dataset 2). Results: Both eyes of 51 glaucoma patients and 67 controls were included in the development dataset. Setting the GHS cutoff at 75 points out of 100, test dataset 1, which comprised 41 subjects with glaucoma and 41 healthy controls, achieved an area under the receiver operating characteristic curve (AUROC) of 0.98, with a sensitivity of 71% and specificity of 98%; test dataset 2, which included 53 patients with glaucoma and 53 healthy controls, resulted in an AUROC of 0.95, with a sensitivity of 75% and specificity of 96%. A decision curve analysis across all datasets demonstrated a higher net benefit for the GHS model compared to individual OCT parameters. Conclusions: The GHS offers a feasible, standardized approach for early detection of glaucoma, providing strong specificity and acceptable sensitivity, with clear decision-making benefits in screening settings.

Efficiency of phacoemulsification handpieces with high and low intraocular pressure settings

Purpose: To compare the efficiencies of the Active Sentry handpiece at low IOP (20 mmHg) to the Ozil handpiece at high IOP (50 mmHg). Setting: Private practice (Medford, OR, USA). Design: Single site, prospective, double-arm, randomized, contralateral eye study. Methods: The first operated eye was randomized to receive phacoemulsification with either the Active Sentry handpiece at 20 mmHg (Active Sentry group) or the Ozil handpiece at 50 mmHg (Ozil group). The second operated eye was assigned to the other group. Outcome measures included phaco time, total aspiration time, aspiration time during phaco, fluid use, cumulative dissipated energy, total torsional time, total longitudinal time, and central corneal thickness. Results: A total of 36 subjects (72 eyes) completed the study. Mean total aspiration time was 90.1 ± 16.4 s in the Active Sentry group and 85.1 ± 17.0 s in the Ozil group (p &gt; 0.05). Mean aspiration time during phaco was 40.9 ± 8.5 s in the Active Sentry group and 40.4 ± 8.8 s in the Ozil group (p &gt; 0.05).Mean total phaco time was 29.5 ± 7.3 s in the Active Sentry group and 31.0 ± 7.4 s in the Ozil group (p &gt; 0.05). Mean total fluid volume was 32.8 ± 4.6 mL in the Active Sentry group and 33.8 ± 6.0 mL in the Ozil group (p &gt; 0.05). Conclusions: The results of this study suggest that the efficiencies of the Active Sentry handpiece at low IOP settings and the Ozil handpiece at high IOP are similar.

Primary Open-Angle Glaucoma Polygenic Risk Score and Risk of Disease Onset

Primary open-angle glaucoma (POAG) is a heritable disease. A polygenic risk score (PRS) threshold may be used to identify individuals at low risk of disease onset. To assess the utility of a POAG PRS to identify ocular hypertensive individuals at low risk of disease onset. This is a post hoc analysis of the Ocular Hypertension Treatment Study (OHTS), a multicenter randomized clinical trial across 22 centers in the US conducted among 1636 participants with ocular hypertension from February 1994 to April 2019 with available genetic data. Of the 1636 original participants, 1077 had available genetic data; after excluding 67 for missing data, data quality concerns, or ancestry other than European or African, 1010 were included in the present analysis. Data for this report were analyzed from November 2023 to June 2024. From 1994-2002, participants were randomized to receive topical intraocular pressure (IOP)-lowering medications. From 2002 onwards, all participants were given topical IOP-lowering medications. Twenty-year conversion rates by POAG PRS threshold, baseline randomization status, and OHTS clinical risk tertile. Among the 1010 participants in this study, 563 (65.8%) were female, and the mean (SD) age was 55.9 (9.4) years. In a mixed-effects logistic regression model adjusted for OHTS risk factors for conversion to POAG and randomization status, a PRS under the 48th percentile was associated with a 1.49 times higher likelihood of disease-free status after 20 years of follow-up (95% CI, 1.04-2.15; P = .03; unadjusted hazard ratio [HR], 1.64; 95% CI, 1.13-2.38; P = .009), compared with high polygenic risk. When we stratified the trial cohort into nongenetic OHTS clinical risk tertiles, the largest differences in survival probability at 20 years based on PRS threshold was observed in eyes in the highest tertile, initial observation group (20-year conversion rate: 61.1% in the high polygenic risk group vs 23.8% in the low polygenic risk group; 95% CI, -63.0 to -11.6; P = .01), with randomization to early treatment partially mitigating the effect of high genetic risk (20-year conversion rate: 37.3% in the high polygenic risk group vs 24.1% in the low polygenic risk group; 95% CI, -35.6 to 9.3%; P = .32). These findings support considering use of a POAG PRS threshold to identify individuals at low risk of disease onset, with those below the PRS threshold more likely to have lower conversion rates over 20 years. Among those considered at highest risk based on the OHTS clinical risk model, early treatment may partially offset the association with high genetic risk but provide limited benefit for those with low genetic risk. ClinicalTrials.gov Identifier: NCT00000125.

Association between ocular diseases and screen time and sedentary time derived from job-exposure matrices

After developing job-exposure matrices (JEMs) for screen and sedentary time, we aimed to assess the associations between the JEM-derived exposures and various ocular diseases. We collected data from patients hospitalized from 2005 to 2021. JEMs were developed from 41,718 patients with occupational information and screen and sedentary times. The adjusted means of screen and sedentary time were calculated for 143 occupational groups and categorized into three classes based on the tertiles. The associations between ocular diseases and these JEM-derived exposures were examined using multivariable conditional logistic regression for 727,589 patients. The odds ratios of the class with highest screen time were 1.05 (95% confidence interval, 1.01–1.09) for cataract, 1.24 (1.06–1.45) for primary open-angle glaucoma (POAG), 1.26 (1.06–1.49) for rhegmatogenous retinal detachment (RRD), 1.49 (1.26–1.76) for ptosis, and 0.39 (0.27–0.57) for pterygium. The odds ratios of the class with highest sedentary time were 1.05 (1.01–1.09) for cataract, 1.24 (1.05–1.46) for RRD, 1.68 (1.42–1.99) for ptosis, and 0.60 (0.42–0.84) for pterygium. Both screen and sedentary time were positively associated with cataract, RRD and ptosis. Interestingly, POAG had a positive association with only screen time. Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary."I have confirmed that the content is correct. No amendments are necessary.Please check article title if captured correctly."?>"I have confirmed that the content is correct. No amendments are necessary.

Genetic Insights and Epidemiological Models in Understanding Primary Open Angle Glaucoma

Primary open-angle glaucoma (POAG) is a multifactorial chronic optic neuropathy with significant genetic heterogeneity. The pathogenesis of POAG involves an imbalance between the production and drainage of aqueous humor (AH). Genetic theories suggest that transgenic mice demonstrating the GLU50LYS mutation in optineurin (OPTN) experience retinal ganglion cell apoptosis, while mutant myocilin (MYOC) proteins induce endoplasmic reticulum (ER) stress, leading to an unfolded protein response (UPR) and subsequent apoptosis of trabecular meshwork cells (TMC). Furthermore, the interaction between MYOC and mitochondria in the trabecular meshwork (TM) and astrocytes may lead to mitochondrial membrane depolarization and calcium channel dysregulation, contributing to POAG. Overexpression of MYOC variants (P370L, Q368X) is also implicated, as are epigenetic modifications and signaling pathways such as histone and DNA modification. POAG has been associated with autosomal dominant inheritance, with mutations in MYOC and OPTN being prominent causative factors, although many cases involve multiple genetic loci. Currently, over 20 genetic loci have been linked to POAG, with 14 chromosomal loci (GLC1A to GLC1N) identified, 5 of which contribute to juvenile-onset open-angle glaucoma (JOAG). Of these loci, MYOC, OPTN, WD repeat domain 36 (WDR36), and neurotrophin-4 (NTF4) are the most studied causative genes. The ongoing study of molecular genetics offers potential pathways for future therapeutic advances in the treatment of POAG.

A small disc size, a big challenge: effect of optic disc size on the correlation between peripapillary choroidal thickness, peripapillary retinal nerve fiber layer, and ganglion cell layer.

We aimed to analyze the effect of optic disc size on the correlation between the peripapillary choroid (PPC), peripapillary retinal nerve fiber layer (RNFL), and macular ganglion cell inner plexiform layer (MGCIPL) thicknesses in subjects with ocular hypertension (OHT) and primary open angle glaucoma (POAG). This study included 61 eyes with a disc area (DA) of ≤ 1.63 mm2, 92 eyes with a DA of 1.63-2.42 mm2, and 59 eyes with a DA of ≥ 2.42 mm2 in small disc, regular disc, and large disc groups, respectively. The swept-source optical coherence tomography scans of the PPC, RNFL, and MGCIPL were analyzed according to disc size. The three groups did not significantly differ in RNFL or MGCIPL measurements, but the PPC measurement was statistically significantly higher in the small disc group and statistically significantly thinner in the large disc group. Most of the correlations observed between the RNFL and MGCIPL measurements and eye characteristics in the regular disc group were not detected in the small and large disc groups. While the RNFL and MGCIPL were well correlated in all disc size groups, the PPC did not correlate with the RNFL or MGCIPL in any of the groups. Overall, the RNFL and MGCIPL measurements were consistent across all three disc sizes. While the PPC was thicker in small discs than in larger discs, it was not correlated with the RNFL or MGCIPL.

Efficacy of Sutureless Scleral Fixation of One-Piece T-Shaped Haptic Intraocular Lens in Maintaining Anterior Chamber Stability During Descemet Membrane Endothelial Keratoplasty in Vitrectomized Eyes: Leak Test and Iris Diaphragm Reconstruction

Objectives: This study aimed to describe the outcomes of a staged procedure combining Descemet membrane endothelial keratoplasty (DMEK) and sutureless scleral fixation (SSF) of a one-piece intraocular lens (IOL) in a case series. Co-performing endothelial keratoplasty (EK) and SSF is associated with intraoperative and postoperative complications such as graft deployment difficulties, air migration, graft detachment, and IOL opacification or tilt, all of which are evaluated in this study. Methods: This is a retrospective observational case series. Clinical data were collected from eight eyes of eight patients who underwent DMEK for endothelial failure and had previously received an SSF with one-piece IOL following complete vitrectomy. During DMEK surgery, an air leak test was conducted to check for air migration into the posterior chamber. If instability was detected, pupilloplasty was performed. Intraoperative and postoperative data, including DMEK graft unfolding time, were collected. Corrected Distance Visual Acuity (CDVA), refraction, endothelial cell density (ECD), central corneal thickness (CCT), intraocular pressure (IOP), and complications were recorded over a 12-month follow-up period. Results: We performed pupilloplasty in four patients (50%). The median CDVA improved from preoperative 0.85 logMAR (range: 0.60 to 1.00) at baseline to 0.18 logMAR (range: 0.10 to 0.70, p = 0.012) at 12 months. The median refraction value changed significantly from −1.00 to −0.50 at 12 months. The median percentage reduction in ECD after 12 months was 33.4% (range 30 to 40). The median baseline CCT was 689 μm (range: 651 to 701) at baseline visit and 541.5 μm (range: 525 to 591, p = 0.008) at 12 months. The median IOP was reduced significantly during follow-up. The median graft unfolding time was 6 min (5 to 9). One patient required rebubbling for partial detachment on postoperative day one. No complications occurred within 12 months. Conclusions: The effective compartmentalization of the anterior and posterior chambers in vitrectomized eyes with an SSF one-piece IOL and pupilloplasty can facilitate critical steps of DMEK surgery in complex eyes. Additionally, the air leak test could prove useful in identifying the need for iris-lens diaphragm reconstruction.

Nyctohemeral effects of topical beta-adrenoceptor blocking agents measured with an intraocular telemetry sensor

ObjectiveTo evaluate nyctohemeral effects of topical beta-adrenoceptor blocking agents and their fixed combinations on intraocular pressure (IOP) in patients with primary open-angle glaucoma implanted with an ocular telemetry sensor.Methods22 patients...

Efficacy of XEN gel stent implantation combined with mitomycin C injection in the treatment of open-angle glaucoma: a meta-analysis

ObjectiveTo assess the efficacy of XEN gel stent implantation combined with mitomycin C (MMC) injection in controlling intraocular pressure (IOP) and the dosage of postoperative medication for open-angle glaucoma (OAG) patients.MethodsThe PubMed, Embase, Cochrane Library, and Science Direct databases were searched from inception to August 2022 without any language restriction. All studies that compared IOP and the dose of medication before and after XEN gel stent implantation and MMC injection for OAG patients were included. Data extraction and methodological quality evaluation were performed.ResultsA total of 26 studies (2329 eyes) were involved in meta-analysis. It was revealed that IOP at 1 month after XEN implantation was significantly lower than preoperative IOP [group 1, IOP between 19.2 and 21.2 mmHg: mean difference (MD) = 7.60, 95% confidence interval (CI) [6.55, 8.66], I2 = 0%, P < 0.01; group 2, IOP between 21.6 and 22.8 mmHg: MD = 5.83, 95% CI [4.94, 6.71], I2 = 0%; group 3, IOP between 23.5 and 24.3 mmHg: MD = 9.22, 95% CI [8.33, 10.10], I2 = 0%; group 4, IOP between 24.4 and 26.2 mmHg: MD = 11.64, 95% CI [10.49, 12.80], I2 = 0%)]. Moreover, IOP at 3 months after XEN implantation was also significantly lower than preoperative IOP (MD = 8.31, 95% CI [2.54, 8.46], Z = 13.92, P < 0.00001). IOP at 6 months after XEN implantation was significantly lower than preoperative IOP, and no heterogeneity was found between two groups (group 1, IOP between 17.8 and 21.8 mmHg: MD = 5.71, 95% CI: [5.05, 6.36], I2 = 0%, P < 0.01); group 2, IOP between 22.1 and 23.9 mmHg: MD = 7.92, 95% CI [7.15, 8.70], I2 = 0%, P < 0.01). Low heterogeneity was noted in one group (group 3, IOP between 24.3 and 26.2 mmHg: MD = 9.32, 95% CI [8.66, 9.97], I2 = 30%). It was found that IOP at 12 months after XEN implantation was significantly lower than preoperative IOP (MD = 8.11, 95% CI [7.09, 9.12], Z = 15.68, P < 0.00001). There was high heterogeneity among the different baseline IOP groups at 24-month post-surgery (CHi2 = 41.74, df = 1, I2 = 97.6%, P < 0.01), while no heterogeneity was identified in two groups (group 1, IOP between 19.2 and 22.1 mmHg: MD = 6.30, 95% CI [5.76, 6.85], I2 = 0%, P < 0.01); group 2, IOP between 22.8 and 23.8 mmHg: MD = 9.11, 95% CI [8.45, 9.77], I2 = 0%). Subgroup analysis indicated that the dosage of medication was significantly reduced at 6 months after XEN implantation (group 1, the amount of medication was 2.3–2.96: MD = 1.90, 95% CI [1.78, 2.02], I2 = 0%, P < 0.01); group 2, the amount of medication was 3.2–3.3: MD = 2.59, 95% CI [2.43, 2.75], I2 = 0%). Furthermore, the dosage of medication at 12 months (MD = 1.96, 95% CI [1.72, 2.21], Z = 15.80, P < 0.01) and 24 months (group 1, the amount of medication was 1.89–2.7: MD = 6.30, 95% CI [5.76, 6.85], I2 = 0%, P < 0.01); group 2, the amount of medication was 2.72–3.07: MD = 9.11, 95% CI [8.45, 9.77], I2 = 0%) after XEN implantation was significantly lower compared with the preoperative level.ConclusionXEN implantation combined with MMC injection significantly decreased IOP in OAG patients at 1, 6, 9, 12, and 24 months after treatment. In addition, XEN implantation combined with MMC injection decreased the amount of medication used at 6, 12, and 24 months after treatment in OAG patients.

A Novel Artificial Endothelial Replacement Membrane for the Treatment of Chronic Corneal Edema.

The purpose of this study was to report the safety and efficacy results of an artificial lamellar implant for the treatment of chronic corneal edema. The EndoArt (EyeYon Medical, Ness Ziona, Israel), an artificial endothelial replacement membrane designed to treat corneal edema, was implanted in 24 eyes of 24 patients with low-to-normal visual potential. We present the safety and efficacy results from a prospective, open-label, single-arm, multicenter study conducted over a 12-month period. Twenty-four patients were enrolled, with no device-related serious adverse events reported. Seventeen patients completed 12-month follow-up, showing a reduction in average central corneal thickness from 759 ± 116 μm to 613 ± 135 μm. Best-corrected distance visual acuity improved from 1.88 ± 0.79 logarithmic minimum angle of resolution (logMAR) to 1.34 ± 0.57 logMAR. Sixty percent gained at least 3 early treatment diabetic retinopathy study (ETDRS) lines. The EndoArt was removed in 5 cases due to incomplete attachment and replaced by corneal transplants; 1 patient was lost to follow-up, and 1 had a procedure failure. No device-related long-term complications, infections, or inflammations were reported. The implants remained transparent throughout the study. The first-in-human results of EndoArt implantation demonstrated the device's potential to treat patients suffering from corneal edema with a favorable safety profile and effective edema reduction in most subjects, with no device-related serious adverse event. The EndoArt may offer a viable solution in regions facing a shortage of donor corneas, as well as for patients who have poor prognosis with human tissue.

What intrinsic factors affect the central corneal thickness?

The cornea is one of the tissues responsible for covering and protecting the inner structures of the eye. Central corneal thickness (CCT) is defined as the distance between the anterior epithelial surface and the posterior surface of the endothelial layer. This parameter plays a very important role regarding intraocular pressure (IOP) measurement, evaluation of corneal uniformity, selection of a suitable technique for corneal refractive surgery and the planning of surgical procedures to overcome corneal disease. This comprehensive review elucidates the multifaceted factors influencing the central corneal thickness. Recognising the impact of these factors not only enhances our understanding of corneal dynamics but also contributes significantly to the refinement of diagnostic and therapeutic strategies in ophthalmology.

Restoration of Corneal Stiffness in Rabbits Following Withdrawal of Travoprost.

To evaluate if the effect of travoprost on corneal material stiffness could be restored after drug withdrawal. Seventy-two rabbits were randomly allocated into three groups: medicine (M), medicine withdrawal (MW), and blank (B). Within the M and MW groups, treatment with travoprost was administered to the right eyes (MT and MWT) over a period of 12 weeks. Subsequently, the M group was killed, but the MW group underwent an additional 12-week period for treatment withdrawal. No treatment was given to the contralateral eyes (MC and MWC) in the M and MW groups. A separate blank control (BC) group remained untreated for the entire 24-week duration. In each group, corneas from 18 rabbits were tested mechanically under inflation conditions to estimate their tangent modulus (Et). The corneas of the remaining six rabbits underwent electron microscopy analysis, which focused on fibril diameter and interfibrillar spacing. Central corneal thickness (CCT) of the treated eyes (MT and MWT groups) decreased with 12 weeks of travoprost treatment (P < 0.05). The CCT in the MWT group increased after 12 weeks of withdrawal but was still lower than that in the BC group (P < 0.05). The Et of the MT group was significantly lower than that of the MC group at mean tissue stresses of 2, 4, and 6 kPa (P < 0.05). Conversely, no significant difference in Et values was observed between the MWT, MWC, and BC groups, indicating recovery after treatment cessation. Furthermore, the stromal interfibrillar spacing of the treated MT group was significantly larger (P < 0.05) than that of the control MC group, but no disparity was noted among the MWT, MWC, and BC groups following treatment withdrawal. Additionally, there were no significant differences in the mean diameter of collagen fibrils among all groups (all P > 0.05). Travoprost treatment appears to soften corneal tissue, decrease tissue thickness, and reduce the density of stromal collagen fibers by increasing the interfibrillar spacing. These changes were partially reversed after treatment cessation. Travoprost could further inhibit corneal growth, so its use in childhood and adolescence should be carefully considered. Additionally, the effect of travoprost in reducing corneal stiffness may lead to underestimations of intraocular pressure (IOP) measurement and hence overestimations in the effect of treatment in lowering IOP.

Evaluating Diagnostic Concordance in Primary Open-Angle Glaucoma Among Academic Glaucoma Subspecialists.

Objective: The study aimed to evaluate the interobserver agreement among glaucoma subspecialists in diagnosing glaucoma and to explore the causes of diagnostic discrepancies. Methods: Three experienced glaucoma subspecialists independently assessed frequency domain optical coherence tomography, fundus color photographs, and static perimetry results from 464 eyes of 275 participants, adhering to unified glaucoma diagnostic criteria. All data were collected from the Wenzhou Glaucoma Progression Study between August 2014 and June 2021. Results: The overall interobserver agreement among the three experts was poor, with a Fleiss' kappa value of 0.149. The kappa values interobserver agreement between pairs of experts ranged from 0.133 to 0.282. In 50 cases, or approximately 10.8%, the three experts reached completely different diagnoses. Agreement was more likely in cases involving larger average cup-to-disc ratios, greater vertical cup-to-disc ratios, more severe visual field defects, and thicker retinal nerve fiber layer measurements, particularly in the temporal and inferior quadrants. High myopia also negatively impacted interobserver agreement. Conclusions: Despite using unified diagnostic criteria for glaucoma, significant differences in interobserver consistency persist among glaucoma subspecialists. To improve interobserver agreement, it is recommended to provide additional training on standardized diagnostic criteria. Furthermore, for cases with inconsistent diagnoses, long-term follow-up is essential to confirm the diagnosis of glaucoma.

Impaired axonal transport at the optic nerve head contributes to neurodegeneration in a novel Cre-inducible mouse model of myocilin glaucoma.

Elevation of intraocular pressure (IOP) due to trabecular meshwork (TM) dysfunction, leading to neurodegeneration, is the pathological hallmark of primary open-angle glaucoma (POAG). Impaired axonal transport is an early and critical feature of glaucomatous neurodegeneration. However, a robust mouse model that replicates these human POAG features accurately has been lacking. We report the development and characterization of a novel Cre-inducible mouse model expressing a DsRed-tagged Y437H mutant of human myocilin (Tg.CreMYOCY437H). A single intravitreal injection of HAd5-Cre induced selective MYOC expression in the TM, causing TM dysfunction, reducing outflow facility, and progressively elevating IOP in Tg.CreMYOCY437H mice. Sustained IOP elevation resulted in significant retinal ganglion cell (RGC) loss and progressive axonal degeneration in Cre-induced Tg.CreMYOCY437H mice. Notably, impaired anterograde axonal transport was observed at the optic nerve head before RGC degeneration, independent of age, indicating that impaired axonal transport contributes to RGC degeneration in Tg.CreMYOCY437H mice. In contrast, axonal transport remained intact in ocular hypertensive mice injected with microbeads, despite significant RGC loss. Our findings indicate that Cre-inducible Tg.CreMYOCY437H mice replicate all glaucoma phenotypes, providing an ideal model for studying early events of TM dysfunction and neuronal loss in POAG.

Association between myopia and sleep duration among primary school students in minority regions of Southwest China: a school-based cross-sectional research.

To investigate the relationship between sleep duration and myopia among primary school students in minority regions of Southwest China. The school-based, cross-sectional study was conducted from October 2020 to January 2021. All participants underwent a comprehensive ocular examination and completed a questionnaire on demographic characteristics, ophthalmological history and major environmental factors for myopia. Spherical equivalent (SE) and ocular biometric parameters were measured after cycloplegia, with myopia being defined as SE ≤-0.5 D (Diopter). Multivariate regression models were used to examine the association of sleep duration with myopia, SE and axial length (AL). A total of 857 students from grades 2 to 4 were included in the analysis, of which 63.6% were myopic and 62.0% belonged to ethnic minorities. Boys had a slightly higher prevalence of myopia compared with girls (66.7% vs 60.6%, p=0.06). Myopic students had longer AL, deeper anterior chamber depth and thinner central corneal thickness compared with non-myopic students (all p<0.05). There was no significant association between sleep duration and myopia in both boys and girls (p=0.319 and 0.186, respectively). Moreover, girls with a sleep duration of 8-9 hour/day had higher SE and shorter AL compared with those with less than 8 hour/day of sleep (β=0.41 and -0.32, respectively, all p<0.05). This cross-sectional study did not find a significant association between sleep duration and myopia. However, it suggests that 8-9 hours of sleep per day may have a protective effect on SE progression and AL elongation in girls. Future studies with objectively measured sleep duration are needed to validate the findings.

Amlodipine increases risk of primary open-angle glaucoma

BackgroundThe use of calcium channel blockers is associated with primary open-angle glaucoma (POAG) in a statistically meaningful but minor way. In general, those who had received calcium channel blocker medication were at a 23% increased risk of developing glaucoma in comparison to those who had never taken the antihypertensive drugs. We wished to confirm this association and examine POAG genes that might be involved, since the genetics has not yet been analyzed.MethodsWe used MedWatch and UK Biobank data to evaluate the effects of amlodipine on POAG and intraocular pressure (IOP). We analyzed three POAG-associated single-nucleotide polymorphisms: rs9913911, an intron variant in growth arrest-specific 7 (GAS7), one of the genes that influences IOP; rs944801, an intron variant within CDKN2B-AS1, and rs2093210, an intron variant within SIX6, known to be associated with vertical cup-disc ratio, an important optic nerve head parameter that is often used to define or diagnose glaucoma.ResultsAmlodipine use in MedWatch doubled the prevalence of POAG, from 0.0805 to 0.177%, a small but significant increase. Multivariate analysis by logistic regression of UK Biobank data revealed that POAG risk was significantly increased with age, male sex, major alleles of rs9913911 (GAS7) and rs944801 (CDKN2B-AS1), and minor allele of rs2093210 (SIX6). Amlodipine increased POAG risk by 16.1% (P = 0.032). Amlodipine has not been associated with increased IOP. We confirmed this lack of association and in addition found that GAS7, associated with IOP, was not associated with POAG risk and amlodipine. But CDKN2B-AS1 and SIX6, POAG genes not associated with IOP, were associated with POAG and amlodipine.ConclusionsAmlodipine, a frequently prescribed drug and first line treatment for hypertension, has a potentially hazardous relationship with POAG. Knowledge of this link can guide the prescribing of alternate drugs for hypertensive individuals who have glaucoma or are at risk for it. Diuretics and β-blockers are not associated with POAG or increased IOP and could be substituted for amlodipine in hypertensive patients at risk POAG.Trial registrationNone.Graphical

Application of Negative Pressure by the Ocular Pressure Adjusting Pump to Provide a Sustained Reduction in IOP.

To evaluate the sustainability of IOP reduction with continuous negative pressure application over an extended duration with use of the Ocular Pressure Adjusting Pump. Prospective, controlled, open-label, randomized, single site, pilot study. Subjects with primary open-angle glaucoma (OAG) were enrolled. One eye of each subject was randomized to receive negative pressure application; the fellow eye served as a control. The study eye negative pressure setting was programmed for 60% of the baseline IOP. Subjects wore the Ocular Pressure Adjusting Pump for 8 consecutive hours and IOP measurements occurred at 2-hour intervals for a total of 5 IOP measurements (08:00, 10:00, 12:00, 14:00, 16:00). Nine subjects successfully enrolled and completed the study. The mean programmed negative pressure setting was -12.0mmHg. At baseline, the mean IOP in the study eye was 21.4 ± 4.3mmHg. The mean IOP reduction in the study eye at hours 0, 2, 4, 6, and 8 was 8.1 (37%), 6.4 (28%), 6.3 (29%), 7.3 (34%) and 6.7 (31%), respectively. All IOP measurements during negative pressure application were reduced from baseline. There were no serious adverse events. The Ocular Pressure Adjusting Pump provides a sustained reduction in IOP while the device is worn with negative pressure applied with an IOP reduction exceeding 25% across 8hours of continuous wear.

The effects of topical latanoprost 0.005% treatment on microvascular changes in the optic nerve head and macula.

This prospective study aimed to assess the impact of topical latanoprost 0.005% treatment on the microvasculature of the macula and optic nerve head (ONH) in primary open-angle glaucoma (POAG). Fifty-seven eyes of 31 subjects were enrolled. ONH whole-image (wiVD), peripapillary (ppVD), and macular vascular density (VD) parameters were measured using optical coherence tomography angiography before treatment, at the 1st month, and at the 3rd month of treatment. There was a significant reduction in IOP post treatment, with a decrease of 17.0 ± 2.3 mmHg in the 1st month and 16.3 ± 2.5 mmHg in the 3rd month (P < 0.001 for both). ONH wiVD and ppVD significantly increased at the post-treatment 1st month (P = 0.001 for both) but decreased by the 3rd month, returning to baseline levels (P < 0.001 for both), indicating a return to pre-treatment levels (P > 0.05 for both). Similarly, macular wiVD and perifoveolar VD (pefVD) increased significantly at the 1st month (P = 0.013 and P < 0.001, respectively) but returned to baseline by the 3rd month (P < 0.001 for both). No significant difference was observed between before-treatment and post-treatment 3rd month regarding the macular wiVD and pefVD (P > 0.05 for both). Deep capillary plexus and foveal avascular zone parameters did not change during follow-up (P > 0.05 for both). The initial increase in ONH and peripapillary VD, as well as macular VD, is attributed to the acute reduction in IOP from topical latanoprost 0.005%. However, the diminishment of sustained differences by the 3rd month indicates adaptation of the ONH and retinal microvasculature to decreased IOP through compensatory mechanisms.

Relationship between corneal hysteresis and the site of damage to peripapillary retinal nerve fibre layer thickness in open-angle glaucoma

Corneal hysteresis (CH) is associated with glaucomatous structural changes. We retrospectively investigated the association between CH and the regional circumpapillary retinal nerve fibre layer thickness (cpRNFLT) in 419 eyes of 419 patients with normal-tension glaucoma (NTG) and primary open-angle glaucoma (POAG). CH was used as the explanatory variable, and cpRNFLT (total and quadrant) was used as the dependent variable. Standardized β coefficients were compared both overall and between the NTG and POAG groups. Multiple regression analysis with CH as the explanatory variable and cpRNFLT parameters as the dependent variables suggested that even after adjusting for age, sex, intraocular pressure (IOP), axial length, and central corneal thickness, all areas of the cpRNFLT were significantly associated with CH, except for the nasal quadrant. In the stratified analysis by glaucoma type, a positive relationship between CH and regional cpRNFLT tended to be maintained in the NTG group but not in the POAG group (P = 0.060 for interaction). Additionally, in the NTG group, the CH-inferior cpRNFLT relationship was particularly strong in the less-IOP fluctuation group. These results suggest that CH may be a potential predictor of anatomical vulnerability around the optic nerve, particularly enhancing the inferior regions of NTG.