Glaucoma Clinic Research Articles

A generalizable deep learning regression model for automated glaucoma screening from fundus images

A plethora of classification models for the detection of glaucoma from fundus images have been proposed in recent years. Often trained with data from a single glaucoma clinic, they report impressive performance on internal test sets, but tend to struggle in generalizing to external sets. This performance drop can be attributed to data shifts in glaucoma prevalence, fundus camera, and the definition of glaucoma ground truth. In this study, we confirm that a previously described regression network for glaucoma referral (G-RISK) obtains excellent results in a variety of challenging settings. Thirteen different data sources of labeled fundus images were utilized. The data sources include two large population cohorts (Australian Blue Mountains Eye Study, BMES and German Gutenberg Health Study, GHS) and 11 publicly available datasets (AIROGS, ORIGA, REFUGE1, LAG, ODIR, REFUGE2, GAMMA, RIM-ONEr3, RIM-ONE DL, ACRIMA, PAPILA). To minimize data shifts in input data, a standardized image processing strategy was developed to obtain 30° disc-centered images from the original data. A total of 149,455 images were included for model testing. Area under the receiver operating characteristic curve (AUC) for BMES and GHS population cohorts were at 0.976 [95% CI: 0.967–0.986] and 0.984 [95% CI: 0.980–0.991] on participant level, respectively. At a fixed specificity of 95%, sensitivities were at 87.3% and 90.3%, respectively, surpassing the minimum criteria of 85% sensitivity recommended by Prevent Blindness America. AUC values on the eleven publicly available data sets ranged from 0.854 to 0.988. These results confirm the excellent generalizability of a glaucoma risk regression model trained with homogeneous data from a single tertiary referral center. Further validation using prospective cohort studies is warranted.

Biochemical-molecular-genetic biomarkers in the tear film, aqueous humor, and blood of primary open-angle glaucoma patients.

Glaucoma is a chronic neurodegenerative disease, which is the leading cause of irreversible blindness worldwide. As a response to high intraocular pressure, the clinical and molecular glaucoma biomarkers indicate the biological state of the visual system. Classical and uncovering novel biomarkers of glaucoma development and progression, follow-up, and monitoring the response to treatment are key objectives to improve vision outcomes. While the glaucoma imaging field has successfully validated biomarkers of disease progression, there is still a considerable need for developing new biomarkers of early glaucoma, that is, at the preclinical and initial glaucoma stages. Outstanding clinical trials and animal-model study designs, innovative technology, and analytical approaches in bioinformatics are essential tools to successfully uncover novel glaucoma biomarkers with a high potential for translation into clinical practice. To better understand the clinical and biochemical-molecular-genetic glaucoma pathogenesis, we conducted an analytical, observational, and case-comparative/control study in 358 primary open-angle glaucoma (POAG) patients and 226 comparative-control individuals (CG) to collect tears, aqueous humor, and blood samples to be processed for identifying POAG biomarkers by exploring several biological pathways, such as inflammation, neurotransmitter/neurotrophin alteration, oxidative stress, gene expression, miRNAs fingerprint and its biological targets, and vascular endothelial dysfunction, Statistics were done by using the IBM SPSS 25.0 program. Differences were considered statistically significant when p ≤ 0.05. Mean age of the POAG patients was 70.03 ± 9.23 years, and 70.62 ± 7.89 years in the CG. Malondialdehyde (MDA), nitric oxide (NO), interleuquin (IL)-6, endothelin-1 (ET-1), and 5 hydroxyindolacetic acid (5-HIAA), displayed significantly higher levels in the POAG patients vs. the CG (p < 0.001). Total antioxidant capacity (TAC), brain derived neurotrophic factor (BDNF), 5-hydroxy tryptamine (5-HT), solute carrier family 23-nucleobase transporters-member 2 (SLC23A2) gene, and the glutathione peroxidase 4 (GPX4) gene, showed significantly lower levelsin the POAG patients than in the CG (p < 0.001). The miRNAs that differentially expressed in tear samples of the POAG patients respect to the CG were the hsa miR-26b-5p (involved in cell proliferation and apoptosis), hsa miR-152-3p (regulator of cell proliferation, and extracellular matrix expression), hsa miR-30e-5p (regulator of autophagy and apoptosis), and hsa miR-151a-3p (regulator of myoblast proliferation). We are incredibly enthusiastic gathering as much information as possible on POAG biomarkers to learn how the above information can be used to better steer the diagnosis and therapy of glaucoma to prevent blindness in the predictable future. In fact, we may suggest that the design and development of blended biomarkers is a more appropriate solution in ophthalmological practice for early diagnosis and to predict therapeutic response in the POAG patients.

Laser‐Responsive Shape Memory Device to Program the Stepwise Control of Intraocular Pressure in Glaucoma

AbstractThere is an unmet need in the glaucoma clinic to control changes in the intraocular pressure (IOP), i.e., patient‐specific hypotony and tissue fibrosis‐mediated ocular hypertension, owing to the fixed tube diameter of the glaucoma drainage device. As a potential solution, the tube diameter can be adjusted, depending on the IOP, by shape memory polymer (SMP) and clinical laser systems, which can control the energy level, focus, and frequency by minimizing untargeted influences. To develop a translatable device, a laser‐responsive SMP with two additional elements: i) a tube with an intimal gel coating to release 5‐fluorouracil as an anti‐fibrotic drug and ii) a safety lock ring to block late hypotony in special cases is employed. When the SMP tube is inserted into a silicone tube and wrapped externally by the ring, intimal gel degradation and argon laser‐triggered diameter increase enable a three‐step IOP control. Sustained drug release of the intimal gel suppresses tissue fibrosis, and the ring prevents late hypotony by externally squeezing the silicone tube. The advanced design and functions are validated using computational in vitro and rabbit glaucoma models by determining clinic‐friendly argon laser parameters.

Quantification of vascular morphology in optical coherence tomography angiography in primary open angle glaucoma

PurposeTo quantitatively measure and compare the vascular morphology in healthy eyes and eyes with primary open-angle glaucoma (POAG) using optical coherence tomography angiography (OCTA) scans. MethodsThis is a retrospective and cross-sectional study which include healthy individuals and individuals with POAG that underwent OCTA imaging at an academic center's glaucoma clinic. We analyzed OCTA scans of the macula and optic nerve head (ONH) of one eye from each subject to quantitatively measure vessel density (VD), vessel length density (VLD), and branchpoint density (BPD). We compared these 3 parameters between the healthy and POAG groups and used logistic regression classification models to determine their diagnostic value in differentiating healthy and glaucomatous eyes. ResultsWe included 49 healthy subjects and 49 subjects with POAG. After age-adjusted analysis, the parameters of VD, VLD, and BPD were significantly reduced in eyes with POAG (P ​< ​0.001) in all scan layers and most significantly around the ONH. The parameter with the best performances were radial peripapillary capillary (RPC) VD [AUC (areas under the curve): 0.939 (0.891, 0.987)] which had statistically higher performances (P ​< ​0.05) than parameters in the superficial or deep layers. All 3 parameters in the RPC layer had statistically similar performances. ConclusionsWe found that VD, VLD, and BPD were reduced in glaucomatous eyes. The morphologic parameters of VLD and BPD had similar performances to the traditional parameter of VD in RPC layers. Our results suggest that vascular morphology parameters may provide additional value in the diagnosis and evaluation of glaucoma.

Potential role of Lycium barbarum polysaccharides in glaucoma management: evidence from preclinical in vivo studies.

In recent years, the pharmacological benefits of herbal extracts have been revisited for their potential neuroprotective effects in glaucoma. The polysaccharides extracted from the fruits of Lycium barbarum L., or Lycium barbarum polysaccharides, exert their anti-aging effect through reducing oxidative stress, modulating the immune response, enhancing neuronal responses, and promoting cytoprotection. The therapeutic efficacy of Lycium barbarum polysaccharides in preserving retinal ganglion cells and their functions was demonstrated in a range of experimental models of optic neuropathies. These include the acute and chronic ocular hypertension models, the partial optic nerve transection model, and the ischemic-reperfusion injuries model. Based on these findings, Lycium barbarum polysaccharides appear to be a good candidate to be developed as a neuroprotective agent for treating multifactorial diseases. This review aims to present a comprehensive review on the latest preclinical evidence on the pre- and post-treatment benefits of Lycium barbarum polysaccharides in retinal ganglion cell neuroprotection. The possible mechanisms of Lycium barbarum polysaccharides mediating retinal ganglion cell neuroprotection will also be described. Moreover, the potential research gaps in the effective translation of Lycium barbarum polysaccharides treatment into clinical glaucoma management will be discussed.

Measures of multiple deprivation and visual field loss in glaucoma clinics in England: lessons from big data

Background/ObjectivesTo examine the association between multiple deprivation with late diagnosis and rapid worsening of glaucoma in patients in English hospital eye services (HES).Methods602,439 visual fields (VFs) were extracted from five regionally different glaucoma clinics in England. Mean Deviation (MD) worse than −12 dB was used as a surrogate definition for advanced VF loss at diagnosis in patients with ≥2 reliable VF records. MD loss worse than -1 dB per year was used to define rapid VF progression in patients with ≥6 VFs. Patient data were stratified into deciles of the Index of Multiple Deprivation (IMD) from residential postcodes.ResultsThere was an association between IMD and advanced VF loss at diagnosis in 44,956 patients with 18% (293/1608) and 11% (771/6929) in the most and least deprived IMD decile, respectively. Age-corrected odds ratio (OR) for having advanced VF loss at entry into HES was 1.42 (95% confidence interval [CI] 1.21–1.67) and 0.75 (95% CI: 0.66–0.85) in the most and least deprived IMD decile respectively (reference = fifth decile). In 15,094 patients with follow up data (median [interquartile range] of 6.9 [4.5, 10.0] years), the proportion having rapid VF progression did not differ across the IMD spectrum.ConclusionLarge-scale VF data from clinics indicates that glaucoma severity at presentation to English HES is associated with levels of multiple deprivation. We found no evidence to suggest likelihood of having rapid VF progression during follow-up is associated with IMD; this hints at equity of glaucoma care and outcomes once patients are in English HES.

The application of artificial intelligence in glaucoma diagnosis and prediction.

Artificial intelligence is a multidisciplinary and collaborative science, the ability of deep learning for image feature extraction and processing gives it a unique advantage in dealing with problems in ophthalmology. The deep learning system can assist ophthalmologists in diagnosing characteristic fundus lesions in glaucoma, such as retinal nerve fiber layer defects, optic nerve head damage, optic disc hemorrhage, etc. Early detection of these lesions can help delay structural damage, protect visual function, and reduce visual field damage. The development of deep learning led to the emergence of deep convolutional neural networks, which are pushing the integration of artificial intelligence with testing devices such as visual field meters, fundus imaging and optical coherence tomography to drive more rapid advances in clinical glaucoma diagnosis and prediction techniques. This article details advances in artificial intelligence combined with visual field, fundus photography, and optical coherence tomography in the field of glaucoma diagnosis and prediction, some of which are familiar and some not widely known. Then it further explores the challenges at this stage and the prospects for future clinical applications. In the future, the deep cooperation between artificial intelligence and medical technology will make the datasets and clinical application rules more standardized, and glaucoma diagnosis and prediction tools will be simplified in a single direction, which will benefit multiple ethnic groups.

Anti-scarring effects of conbercept on human Tenon’s fibroblasts: comparisons with bevacizumab

BackgroundSafely inhibiting the formation of scar in the glaucoma filtration surgery (GFS) has always been an issue for clinical glaucoma doctors. Anti-vascular endothelial growth factor (VEGF) agents can reduce angiogenesis, and anti-placental growth factor (PIGF) agents can affect reactive gliosis. However, the effect of conbercept, which can bind to both VEGF and PIGF, on human Tenon’s fibroblasts (HTFs) is unknown.MethodsHTFs were cultured in vitro and treated with conbercept or bevacizumab (BVZ). No drug was added to the control group. The effects of drugs on cell proliferation were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the collagen type I alpha1(Col1A1) mRNA expression level was measured using quantitative polymerase chain reaction (qPCR). HTF cell migration after drug interventions was evaluated using the scratch wound assay along with the measurement of the expression levels of VEGF and PIGF in human umbilical vein endothelial cells (HUVECs) using enzyme-linked immunosorbent assay, as well as the detection of the VEGF(R) mRNA expression level in HTFs using qPCR.ResultsAfter the addition of conbercept (0.01, 0.1, and 1 mg/mL) to the cultured HTFs or HUVECs, no significant cytotoxicity was observed compared with the control group, while the cytotoxicity of 2.5 mg/mL BVZ on HTFs was obvious. Conbercept significantly inhibited HTF cell migration and Col1A1 mRNA expression level in HTFs. It was superior to BVZ in inhibiting HTF migration. After the intervention with conbercept, the expression level of PIGF and VEGF in HUVECs significantly decreased; and the inhibitory effect of conbercept on the expression level of VEGF in HUVECs was weaker than that of BVZ. Conbercept was more advantageous than BVZ in inhibiting the expression level of VEGFR-1 mRNA in HTFs. However, its effect in terms of inhibiting the expression level of VEGFR-2 mRNA in HTFs was weaker than that of BVZ.ConclusionThe results suggested the low cytotoxicity and significant anti-scarring effect of conbercept in HTF with significant anti-PIGF and inferior anti-VEGF effects compared with BVZ, thus providing a better understanding of the role of conbercept in the GFS wound healing process.

Watching intense movies increase IOP of primary open angle glaucoma patients: A prospective study

To investigate intraocular pressure (IOP) changes while viewing smartphone movies under artificial intelligence (AI) monitoring. In all, 48 subjects were recruited from the glaucoma clinic of Xianyou maternal and child health hospital from January 2018 to March 2020. The research consisted of three parts. In part 1, movies rated by the Motion Picture Association of America (MPAA) were viewed via smartphones of various screen sizes under AI supervision for 90minutes, at a distance of 40cm. IOP and biological parameters including anterior chamber angle, Schlemm's canal (SC) cross-sectional area, heart rate, systolic and diastolic blood pressures (SBP and DBP) were measured and analyzed. In part 2, blue-blocking glasses (BB glasses) were worn to repeat the above experiments. In part 3, the efficacy of AI in decreasing attention loss was analyzed. In addition, results were analyzed to determine whether interval breaks, prompted by AI, prevented IOP from rising. In part 1, the mean IOP of primary open angle glaucoma (POAG) subjects' right eyes significantly increased by 4.828 and 4.974mmHg after watching R and NC-17movies, respectively. In their left eyes, it increased by 2.876 and 5.767 after watching R and NC-17movies, respectively. The maximum IOP difference was also increased by 4.782 and 4.510 on right and left eyes, respectively, after viewing NC-17 movies on a 6.1-inch screen. Furthermore, the SC became narrower, whereas heart rate, DBP and SBP increased in the POAG group. In addition, maximum IOP difference was significantly correlated with SC cross-sectional area, DBP and SBP in the POAG group. In part 2, symptom scores were improved by BB glasses; however, IOP was not decreased. In part 3, attention loss was significantly decreased by AI monitoring. On the contrary, AI also prevented IOP from rising via promoting interval rest. Watching adult movies (NC-17) can significantly increase the IOP of POAG patients. AI can prevent IOP from rising by promoting interval rest when viewing NC-17 movies.

Towards an extended EfficientNet-based U-Net framework for joint optic disc and cup segmentation in the fundus image

PurposeAutomatic and accurate segmentation of the optic disc (OD) and optic cup (OC) is crucial for clinical glaucoma screening. However, the segmentation accuracy cannot meet the requirements of clinical diagnosis yet. This paper aims to propose a novel joint segmentation framework to improve accuracy. MethodsWe suggested an extended EfficientNet-based U-Net, named EE-UNet. First, we use the EfficientNet to extract distinguishable features under different scales of receptive fields. Second, we employ the Conditional Random Field as a Recurrent Neural Network (CRF-RNN) to extend the U-Net framework, maintaining an end-to-end mode. Third, the Ranger optimizer is suggested for faster and more stable convergence with minimal computational cost. Finally, we designed a multi-label loss function to balance the foreground and background pixels. ResultsExtensive experiments were trained and verified on the datasets REFUGE and GAMMA and tested on Drishti-GS1 and RIM-ONE-v3. The proposed EE-UNet achieved a high DICE score in OD/OC segmentation (0.9624/0.9228, respectively), outperforming the state-of-the-art (SOTA) methods. ConclusionQuantitative and qualitative results verified the superior performance of the proposed method in OC and OD segmentation, thus proving that it can be a promising tool in the early screening of large-scale glaucoma.

The relationship between multiple deprivation and severity of glaucoma at diagnosis.

Socioeconomic deprivation is associated with higher odds of chronic diseases, with many individuals living with more than one illness. This study aimed to examine the relationship between deprivation and severity of glaucoma at diagnosis, an important risk factor for glaucoma blindness. A retrospective study of 472 consecutive patients referred by community optometrists to the glaucoma clinic at a university hospital was performed. Glaucoma severity was determined by standard automated perimetry mean deviation (MD) in the worse eye. The Scottish Index of Multiple Deprivation (SIMD) was determined for each patient as a measure of deprivation based on postcode. Regression analyses were performed to determine the relationship between visual field MD and SIMD. There was a significant relationship between higher levels of deprivation (lower SIMD) and worse severity of glaucoma at diagnosis. 32 of 472 patients (6.8%) had a MD of ≤-6 dB and 11 (2.3%) ≤-12 dB in their better eye. MD in the worse eye was 0.04 dB (95% CI 0.014 to 0.062 dB, P = 0.002) worse for each 100-point decrease in SIMD, with lower SIMD indicating a higher level of deprivation. A higher proportion of patients living in most deprived areas had a MD ≤ -6 dB or ≤ -12 dB at presentation compared to those living in the least deprived areas (14.3% versus 6.8% for ≤ -6 dB and 4.8% versus 0.8% for ≤ -12 dB). Higher levels of deprivation were associated with worse glaucoma severity at presentation. The reasons for poorer outcomes in those from more deprived communities need further study so that inequalities can be addressed and the frequency of patients presenting with advanced glaucoma reduced.

Three‐year outcomes of an optometrist‐led virtual clinic for new glaucoma referrals

The purpose of this study was to describe and evaluate the outcomes of an optometrist-led virtual glaucoma clinic (VGC). New patients referred to the glaucoma service who were consultant triaged as 'low risk' were assessed virtually by specialist-trained optometrists in the VGC and either discharged or monitored for a period of 3 years. Ten percent of virtual case notes were audited by a glaucoma consultant to verify quality and generate learning objectives. Retrospective case-note review and analysis of all patients seen in the virtual clinic between 2014 and 2016 was undertaken to determine 3-year outcomes. A total of 1710 new patients were seen in the clinic between 1 January 2014 and 31 December 2016. Of these, 1033 (60.4%) patients required no outpatient input in 3 years of follow-up. Additionally, 320 (18.7%) were discharged at the first visit, and the proportion of glaucoma suspect and ocular hypertension patients who converted to glaucoma was 12.1% and 5.8%, respectively. At 3 years, 95 patients had died, 159 were lost to follow-up, 576 were discharged and 371 were diagnosed with glaucoma at baseline or during the 3-year follow-up. The cumulative discharge proportion from the service at the end of 3 years was 82.6%. No patients required emergency eye treatment or sight-impairment registration, and of the 12 referred back to the clinic on discharge, only five required ongoing monitoring. This optometrist-led VGC combined two aspects of novel service delivery to reduce the burden of glaucoma monitoring in outpatient departments and consolidate consultant contact to patients requiring more intervention. This model will be of value in units establishing virtual services and looking to expand the role of allied health professionals.

Comparison of Perimetric Outcomes from a Tablet Perimeter, Smart Visual Function Analyzer, and Humphrey Field Analyzer

The tablet-based Melbourne Rapid Fields (MRF) visual field (VF) test and the IMOvifa Smart Visual Function Analyzer (SVFA) are portable perimeters that may allow for at-home monitoring and more frequent testing. We compared tablet and SVFA results with outputs from the Humphrey Field Analyzer (HFA) 24-2 Swedish Interactive Threshold Algorithm Standard program. Observational cross-sectional study. Adult participants with a diagnosis of glaucoma, suspected glaucoma, or ocular hypertension seen in the Massachusetts Eye and Ear glaucoma clinic were enrolled. All participants were reliable and experienced HFA testers. Participants were tested with the SVFA and HFA. The study staff also trained participants on the MRF tablet with instructions to take weekly tests at home for 3 months. Visual field results from the 3 devices were compared. Mean deviation (MD), pattern standard deviation (PSD), reliability parameters, and point sensitivity. Overall, 79 participants (133 eyes) with a mean age of 61±13 years (range, 26-79 years) were included; 59% of the participants were female, and the mean HFA MD was-2.7±3.9 dB. The global indices of MD and PSD did not significantly vary between HFA and the 2 novel devices, except that the tablet VF reported a 0.6 dB higher PSD compared with HFA. However, tablet and SVFA sensitivities significantly differed from those of the HFA at 36 and 39 locations, respectively, out of 52 locations. Relative to HFA, the tablet overestimated light sensitivity in the nasal field while underestimating the temporal field. The SVFA generally underestimated light sensitivity, but its results were more similar to HFA results compared with the tablet. Although average MD values from the 2 novel devices suggest that they provide similar results to the HFA, point-by-point comparisons highlight notable deviations. Differences in specific point sensitivity values were significant, especially between the tablet and the other 2 devices. These differences may in part be explained by differences in the devices' normative databases as well as how MD is calculated. However, the tablet had substantial differences based on location, indicating that the tablet design itself may be responsible for differences in local sensitivities. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Feasibility of providing collaborative glaucoma care from a community optometry perspective: a mixed-methods assessment

ABSTRACT Clinical relevance Despite evidence showing that optometry-led collaborative glaucoma care can be delivered at reduced cost compared to ophthalmology-based care without compromising patient outcomes, such models of care are not widely practiced in Australia. Ensuring glaucoma patients have equitable access to effective and cost-effective care is a matter of public health importance. Background This study examined the feasibility and business case assessment for providing glaucoma care from a community optometry perspective. Methods Nine optometrists were interviewed in a semi-structured format, focusing on the economic feasibility, barriers, and benefits of collaborative glaucoma care. The Consolidated Framework for Intervention Research was used for thematic data analysis. Costs and revenues associated with providing glaucoma care were sourced from the literature and interviews. A business case model assessing the profitability of glaucoma care in optometric practice was developed. Results Thematic analysis revealed concerns over financial viability such that current Medicare Benefits Schedule fees are not sufficient to justify the cost of running a community optometry glaucoma clinic. All participants received a supplementary source of revenue. This finding was confirmed by the business case assessment. Inter-professional trust was perceived to be a key barrier to initiation of collaborative care however was able to be overcome quickly upon commencement of a collaborative care relationship. Optometrists perceived that collaborative care was beneficial to all involved, including patients, ophthalmologists, optometrists, and health payers. There was a perception of a growing divide between clinical and retail optometry, which was thought by most participants to be appropriate. Conclusion This study is the first to explore the feasibility and business case for community-based optometrists to provide collaborative glaucoma care in Australia. Our findings show that current public funding is insufficient to justify the business case to private optometry practice, despite being perceived by optometrists as beneficial to all involved.

Identifying Risk Factors for Blindness From Glaucoma at First Presentation to a Tertiary Clinic

Glaucoma is the leading cause of irreversible blindness, a crippling disability resulting in higher risks of chronic health conditions. To better understand disparities in blindness risk, we identified risk factors of blindness on first presentation to a glaucoma clinic using a large clinical database. Retrospective cross-sectional study. We used electronic health records of glaucoma patients from the Duke Ophthalmic Registry. International Classification of Diseases codes were used to identify glaucoma and exclude concurrent diseases. Blindness classification was based on the definition of legal blindness. Risk factors included gender, race, marital status, age, intraocular pressure, diabetes history, income level, and education. Odds ratios (ORs) and 95% CIs were calculated for risk factors using univariable and multivariable logistic regression. Our cohort consisted of 3753 patients, with 192 (5%) blind on first presentation. In univariable models, African American / Black race (OR 2.48, 95% CI 1.83-3.36), single marital status (1.74, 95% CI 1.25-2.44), prior diabetes diagnosis (2.23, 95% CI 1.52-3.27), and higher intraocular pressure (1.29 per 1 SD higher, 95% CI 1.13-1.46) were associated with increased risk of presenting blind, whereas higher annual income (0.75, 95% CI 0.65-0.86) and education (0.77, 95% CI 0.69-0.85) were associated with lower risk. These associations remained significant and in the same direction in a multivariable model apart from income, which became insignificant. Using a large real-world clinical database, we identified risk factors associated with presentation with blindness among glaucoma patients. Our results highlight disparities in health care outcomes and indicate the importance of targeted education to reduce disparities in blindness.

Lockdown: The Impact on Management of Glaucoma in a Suburban Tertiary Centre in Malaysia.

The COVID-19 pandemic brought the world to a standstill in 2020. Many countries have imposed lockdowns, known as the movement-control order (MCO) in Malaysia, to prevent transmission of the disease. The objective of this study is to evaluate the impact of the MCO on the management of glaucoma patients in a suburban tertiary hospital. We conducted a cross-sectional study of 194 glaucoma patients between June 2020 and August 2020 in the glaucoma clinic at Hospital Universiti Sains Malaysia. We evaluated the patients' treatment, visual acuity, intraocular pressure (IOP) measurements, and potential signs of progression. We compared the results with those of their last clinic visits prior to the MCO. We studied 94 (48.5%) male and 100 (51.5%) female glaucoma patients with a mean age of 65 ± 13.7. The mean duration between pre-MCO and post-MCO follow-up was 26.4 ± 6.7 weeks. There was a significant increase in the number of patients with deterioration of visual acuity, and one patient lost his vision after the MCO. There was also a significant elevation of the mean IOP of the right eye: pre-MCO, 16.7 ± 7.8 mmHg, compared to post-MCO, 17.7 ± 8.8 mmHg (p = 0.027). The cup-to-disc ratio (CDR) for the right eye increased significantly from pre-MCO, 0.72 ± 0.18, to 0.74 ± 0.19 post-MCO (p < 0.001). However, there were no significant changes in IOP or CDR in the left eye. Twenty-four patients (12.4%) missed medications during the MCO period, and 35 patients (18%) required additional topical medications due to the progression of the disease. Only one patient (0.5%) required admission due to uncontrolled IOP. Lockdown, as a preventive step in the COVID-19 pandemic, indirectly caused the progression of glaucoma and uncontrolled IOP.

Global and sectoral retinal nerve fiber layer thickness in glaucoma suspects and primary open-angle glaucoma patients attending a tertiary care center in South India

ABSTRACT Background: Spectral-domain optical coherence tomography (OCT) can identify the presence of localized glaucomatous structural damage. The peripapillary retinal nerve fiber layer (RNFL) thickness is a popular OCT parameter used for glaucoma diagnosis and monitoring progression. Aim: To measure the peripapillary RNFL thickness, the pattern of RNFL defect, and association of RNFL with the severity of glaucoma using Spectralis Spectral Domain – OCT in patients with primary open-angle glaucoma (POAG) at a glaucoma clinic in a tertiary care teaching hospital in south India. Methods: Cross-sectional study design. Peripapillary RNFL thickness of 109 glaucomatous eyes of 56 patients aged 40–75 years having POAG, ocular hypertension, or suspected to have glaucoma but without visual field (VF) defects were included in the study. The cross-sectional thickness of RNFL using a 3.46 mm circle centered around the disc in 6 segments were measured and defects in the RNFL were identified by comparing measurements from each patient with the normative database. Results: The study included 109 eyes with 51 (46.79%) preperimetric eyes and 58 (53.21%) POAG eyes (with field defects). The average global thickness in the study population was 91.31 ± 12.81 µm for preperimetric eyes and 67.76 ± 17.33 µm for eyes with glaucoma. There was significant thinning in all segments between eyes with POAG and normal eyes with the mean difference highest in the inferotemporal segment (mean difference of 73.05) and the superotemporal segment (mean difference of 55.85). The global RNFL thickness had a coefficient of − 0.015 (standard error [SE] 0.003, 95% confidence interval [CI]: 0.02–0.009, R2 = 0.29) for mild glaucoma, −0.010 (SE 0.004, 95% CI: 0.02–0.003, R2 = 0.12) for moderate and − 0.18 (SE: 0.001, 95% CI: 0.022–0.014, R2 = 0.60) for severe glaucoma compared to preperimetric eyes in a linear regression model that adjusted for age and gender. Global and sector-wise RNFL thickness also had a significant area under Receiver Operator Characteristic (0.84, 95% CI: 0.78. 0.91) that showed the ability to discriminate between preperimetric and glaucomatous eyes. Possible “floor effect” of RNFL thickness was shown by 7 eyes with advanced glaucoma cases. Conclusion: RNFL thinning can be used as a parameter to assess glaucomatous structural loss that can aid in early diagnosis and monitoring of disease progression, to grade the severity of the disease in primary open-angle glaucoma, and when VFs cannot be done.

Prevalence of Myocilin Gene Mutation in Adult-Onset Primary Open Angle Glaucoma and Non-Glaucoma Subjects Who Are Indigenes of Rivers State, Nigeria

Background: Glaucoma is the leading cause of irreversible blindness incapacitating over 80 million people worldwide. Several pathogenetic mechanisms have been postulated to explain the optic nerve damage that occur in POAG among which genetic predisposition is prominent. Gene-Linkage-based studies have identified genes associated with POAG: Myocilin, Optineurin, WDR36, Tank-Binding Kinase (TBK1) and APbb-2. Objective: To investigate the prevalence of myocilin gene mutation in adult-onset POAG patients and non-glaucoma subjects who are indigenes of Rivers State. Methodology: In this comparative cross-sectional study, 393 POAG patients attending the Glaucoma Clinic of UPTH were compared with 393 age and sex-matched phenotypically normal participants. Clinical assessment combined with findings from clinical records was used. Venous blood was obtained for genomic analyses. Extracted DNA was sequenced with specific primers for myocilin and polymerase chain reaction. Zymo-Bead Genomic DNA kit protocol was used to detect allelic differences. Results: Total of 786 participants participated in the study. The mean age was 59.8 ± 11.8 years. The prevalence of myocilin gene mutation (MYOC) in the study population was 5.3%, in the POAG group was 8.4%, and 2.3% in the non-glaucoma group. This observed difference was statistically significant (p = 0.001). Location of the mutant myocilin gene was in GLC1A 171638779, 171638703, 171638610 and 171638608. Conclusion: Mutations in myocilin gene are associated with adult-onset POAG in Rivers State. Its relevance as a biomarker for diagnosis of adult-onset POAG needs further investigations.

Demographic and Socioeconomic Characteristics of Glaucoma Suspects in a Tertiary Care Center of Pakistan

Purpose: To describe the demographic characteristics of Glaucoma Suspects (GS) presenting to the glaucoma clinic in a tertiary care settings. Study Design: Descriptive observational study. Place &amp; Duration of Study: Glaucoma clinic of Al-Shifa Trust Eye Hospital, Rawalpindi, from September 2015 to February 2016. Methods: Patients attending the glaucoma clinic were examined and intraocular pressure (IOP), iridocorneal angles, anterior and posterior segments evaluation, vertical cup-to-disc ratio (vCDR) were measured. Retinal nerve fiber (RNFL-Global) thickness was calculated by the Optical Coherence tomography machine using software version 6.0.9. Subjects qualifying as glaucoma suspects were interviewed for demographic and systemic conditions. All the information was recorded on a predesigned proforma and descriptive statistics was used for analysis. Results: A total of 876 patients were examined. Eighty-two (9.36%) patients fulfilled the criteria of GS. There were 57.3% females and mean age of sample was 56.78 ± 12.83 (Range 40 – 70 years). Hypertension was found in 34.1% (n = 28) and diabetes in 25.6% (n = 21). Other diseases were asthma, depression, cardiac and gastric problems. Most of the patients belonged to lower or upper lower class, which represents a huge number on socioeconomic status scale. Mean IOP (both eyes) was 13.93 ± 3.23 mmHg (range 6 – 22 mmHg). Only 5% of subjects had vCDR of &gt; 0.8.RNFL-Global of 79 (48.2%) eyes were within normal limits. Conclusions: Majority of GS belong to lower or lower middle socioeconomic class. The health authorities must focus on this issue to provide easily accessible diagnostic facilities for reducing the economic burden of this problem.

Rhopressa Clinical Use: A Case Series

Purpose. The aim of this paper is to discuss and highlight via case reports the effective use of Rhopressa in three individual cases of Primary Open-Angle Glaucoma (POAG) treated at a glaucoma clinic in Philadelphia, PA, USA. The cases display the clinical use of netarsudil and reviews therapeutic approach- es to combating the side effects of conjunctival hyperemia associated with netarsudil. Material and Methods. A systematized PubMed literature search based on the terms “Rhopressa”, “netarsudil”, “ROCK inhibition” was conducted. Six eyes of three adult patients were monitored for three months after beginning treatment with Rhopressa (0.02 % netasurdil ophthalmic solution, Aerie Pharmaceuticals Inc, Durham, NC, 2018). Results. In all three cases, an efficacious response was achieved with all three patients obtaining an intraocular pressure of 13 mmHg or lower. In two out of three cases the patients were taking three or more medications prior to the addition of Rhopressa (0.02 % netasurdil ophthalmic solution, Aerie Pharmaceuticals Inc, Durham, NC, 2018). Two eyes out of six possessed a stage of severe glaucoma and two out of six eyes previously underwent multiple surgical glaucoma interventions. Conclusion. A desirable intraocular pressure reduction was found in all six eyes out of three patients with an accept- able tolerability of use of the medication. Rhopressa (0.02 % netasurdil ophthalmic solution, Aerie Pharmaceuticals Inc, Durham, NC, 2018) is a viable and effective adjunct therapy for the treatment of open-angle glaucoma with adequate patient tolerability. Keywords Primary Open Angel Glaucoma (POAG), glaucoma treatment, intraocular pressure, Rhopressa