Early Glaucoma Research Articles

Fundus- Based Glaucoma Detection- Machine Learning A Design Approach

Glaucoma is a leading cause of irreversible blindness worldwide, characterized by the progressive degeneration of the optic nerve, often associated with increased intraocular pressure. This paper proposes a machine learning-based design approach for the detection of glaucoma using fundus images. Our approach leverages advanced image processing techniques and machine learning algorithms to identify glaucomatous features in fundus images. The system comprises several key components: pre-processing of fundus images to enhance quality, feature extraction to identify relevant glaucomatous markers, and classification using machine learning models to differentiate between healthy and glaucomatous eyes. The proposed model achieved high accuracy, sensitivity, and specificity in detecting glaucoma, demonstrating its potential as a reliable and non-invasive diagnostic tool. Our findings highlight the efficacy of machine learning in medical imaging applications and underscore the importance of automated systems in assisting ophthalmologists in early glaucoma detection

Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma.

To assess the performance of macular ganglion cell-inner plexiform layer thickness (mGCIPLT) and 10-2 visual field (VF) parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma. Totally 127 eyes from 89 participants (36 eyes of 19 healthy participants, 45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients) were included. The relationships between the optical coherence tomography (OCT)-derived parameters and VF sensitivity were determined. Patients with early glaucoma were divided into eyes with or without central 10° of the VF damages (CVFDs), and the diagnostic performances of OCT-derived parameters were assessed. In early glaucoma, the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation (PSD; with average mGCIPLT: β=-0.046, 95%CI, -0.067 to -0.024, P<0.001). In advanced glaucoma, the mGCIPLT was related to the 24-2 VF mean deviation (MD; with average mGCIPLT: β=0.397, 95%CI, 0.199 to 0.595, P<0.001), 10-2 VF MD (with average mGCIPLT: β=0.762, 95%CI, 0.485 to 1.038, P<0.001) and 24-2 VF PSD (with average mGCIPLT: β=0.244, 95%CI, 0.124 to 0.364, P<0.001). Except for the minimum and superotemporal mGCIPLT, the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without CVFDs. The area under the curve (AUC) of the average mGCIPLT (AUC=0.949, 95%CI, 0.868 to 0.982) was greater than that of the average circumpapillary retinal nerve fiber layer thickness (cpRNFLT; AUC=0.827, 95%CI, 0.674 to 0.918) and rim area (AUC=0.799, 95%CI, 0.610 to 0.907) in early glaucomatous eyes with CVFDs versus normal eyes. The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF, cpRNFLT and ONH parameters, especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level.

MP-3 microperimeter in early primary open angle glaucoma with a new pattern.

To investigate macular microperimetry in patients with early primary open angle glaucoma (POAG) using a new custom-made pattern, and analyze the characteristics of macular sensitivity. This case-control study included 38 patients with POAG, who were divided into pre-perimetric glaucoma (18 eyes of 18 patients), early-stage (20 eyes of 20 patients), and control (20 eyes of 20 patients) groups. All subjects underwent standard 24-2 humphrey visual field test. An MP-3 microperimeter with a new custom-made pattern (28 testing points distributed in four quadrants, covering the central 10° of the retina) was used to evaluate macular sensitivity. Ganglion cell complex (GCC) thicknesses were examined using an RS-3000 Advance OCT system. The features of structure and function were analysed per quadrant. The pre-perimetric glaucoma group had significantly lower inferior hemifield macular sensitivity compared to controls (P<0.05). The early-stage POAG group had significantly lower average, inferior hemifield, inferonasal, and inferotemporal mean sensitivities compared to the pre-perimetric glaucoma group (P<0.05), and lower macular sensitivity in all sectors compared to controls (P<0.05). Regarding GCC thickness, all sectors in the early-stage POAG group became thinner compared to those in controls (P<0.05); whereas all sectors in the early-stage POAG group, except the superonasal quadrant, became thinner compared to those in the pre-perimetric glaucoma group (P<0.05). Macular sensitivity and GCC thickness were significantly associated in each sector. The inferotemporal quadrant had the highest correlation coefficients (0.840). The structure-function relationship for the inferonasal and inferotemporal sectors was stronger compared to the corresponding superior sectors. Microperimetry reveals variations in macular sensitivity in patients with early glaucoma earlier than conventional perimetry, particularly in pre-perimetric glaucoma cases in which it might be undetectable by conventional methods. The new custom-made pattern may improve the accuracy of microperimetry by enhancing point arrangement and reducing fatigue effects. Macular sensitivity measured by MP-3 with this pattern shows statistically significant structural and functional associations with the thicknesses of the GCC.

Retinal Nerve Fiber Layer Damage Assessment in Glaucomatous Eyes Using Retinal Retardance Measured by Polarization-Sensitive Optical Coherence Tomography.

To assess the diagnostic performance and structure-function association of retinal retardance (RR), a customized metric measured by a prototype polarization-sensitive optical coherence tomography (PS-OCT), across various stages of glaucoma. This cross-sectional pilot study analyzed 170eyes from 49 healthy individuals and 68 patients with glaucoma. The patients underwent PS-OCT imaging and conventional spectral-domain optical coherence tomography (SD-OCT), as well as visual field (VF) tests. Parameters including RR and retinal nerve fiber layer thickness (RNFLT) were extracted from identical circumpapillary regions of the fundus. Glaucomatous eyes were categorized into early, moderate, or severe stages based on VF mean deviation (MD). The diagnostic performance of RR and RNFLT in discriminating glaucoma from controls was assessed using receiver operating characteristic (ROC) curves. Correlations among VF-MD, RR, and RNFLT were evaluated and compared within different groups of disease severity. The diagnostic performance of both RR and RNFLT was comparable for glaucoma detection (RR AUC = 0.98, RNFLT AUC = 0.97; P = 0.553). RR showed better structure-function association with VF-MD than RNFLT (RR VF-MD = 0.68, RNFLT VF-MD = 0.58; z = 1.99; P = 0.047) in glaucoma cases, especially in severe glaucoma, where the correlation between VF-MD and RR (r = 0.73) was significantly stronger than with RNFLT (r = 0.43, z = 1.96, P = 0.050). In eyes with early and moderate glaucoma, the structure-function association was similar when using RNFLT and RR. RR and RNFLT have similar performance in glaucoma diagnosis. However, in patients with glaucoma especially severe glaucoma, RR showed a stronger correlation with VF test results. Further research is needed to validate RR as an indicator for severe glaucoma evaluation and to explore the benefits of using PS-OCT in clinical practice. We demonstrated that PS-OCT has the potential to evaluate the status of RNFL structural damage in eyes with severe glaucoma, which is currently challenging in clinics.

Reduced Thickness of the Retina in de novo Parkinson's Disease Shows A Distinct Pattern, Different from Glaucoma.

Parkinson's disease (PD) patients experience visual symptoms and retinal degeneration. Studies using optical coherence tomography (OCT) have shown reduced thickness of the retina in PD, also a key characteristic of glaucoma. To identify the presence and pattern of retinal changes in de novo, treatment-naive PD patients compared to healthy controls (HC) and early primary open angle glaucoma (POAG) patients. Macular OCT data (10×10 mm) were collected from HC, PD, and early POAG patients, at the University Medical Center Groningen. Bayesian informative hypotheses statistical analyses were carried out comparing HC, PD-, and POAG patients, within each retinal cell layer. In total 100 HC, 121 PD, and 78 POAG patients were included. We showed significant reduced thickness of the inner plexiform layer and retinal pigment epithelium in PD compared to HC. POAG patients presented with a significantly thinner retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, outer plexiform layer, and outer photoreceptor and subretinal virtual space compared to PD. Only the outer segment layer and retinal pigment epithelium were significantly thinner in PD compared to POAG. De novo PD patients show reduced thickness of the retina compared to HC, especially of the inner plexiform layer, which differs significantly from POAG, showing a more extensive and widespread pattern of reduced thickness across layers. OCT is a useful tool to detect retinal changes in de novo PD, but its specificity versus other neurodegenerative disorders has to be established.

Association of Long-Term Intraocular Pressure Variability and Rate of Ganglion Complex Thinning in Patients With Glaucoma

To evaluate the association of mean intraocular pressure (IOP) and IOP variability (IOP fluctuation [SD of IOP] and the IOP range) with the rate of ganglion cell complex (GCC) layer thinning over time in patients with glaucoma. Prospective cohort study. Participants with at least 4 visits and 2 years of follow-up of optical coherence tomography tests were included. A linear mixed-effect model was used to investigate the association of IOP parameters with the rates of GCC thinning. Subgroup analyses were conducted for eyes with early (MD ≥ -6 dB), and moderate to advanced stage (MD < -6 dB) at baseline. The cohort consisted of 369 eyes of 249 glaucoma patients (282 early glaucoma and 87 moderate to advanced glaucoma) with mean (standard deviation [SD]) age of 68.2 (10.7) years over 5.1 years of follow-up. The mean rate of GCC change was -0.59 (95% confidence interval [CI], -0.67 to -0.52) µm per year. In multivariable models, faster annual rate of GCC thinning was associated with a higher IOP fluctuation (-0.17 [95% CI, -0.23 to -0.11] µm per 1-mmHg higher, P < .001) or higher IOP range (-0.07 [95% CI, -0.09 to -0.05] µm per 1-mmHg higher, P < .001) after adjustment for mean IOP and other confounding factors. Similar results were found for early and moderate to advanced stages of glaucoma. IOP variability showed an independent association with macular change in patients with glaucoma regardless of severity at baseline, even after adjustment for mean IOP, supporting its potential value as a therapeutic target for clinical decision-making.

Case series: Superficial plexus en face may aid distinction of retinal nerve fiber layer loss from diabetic retinal ischemia versus glaucoma.

This study aimed to demonstrate that the pattern and degree of capillary bed dropout in early glaucoma appear different on OCT-A superficial plexus en-face slabs compared with retinal ischemia. RNFL loss associated with retinal ischemia in diabetic patients may be explained and accounted for by overlying the RNFL deviation map on a superficial plexus en-face montage. Three middle-aged White men with diabetes mellitus showed cup-to-disc ratios of approximately 0.7 and RNFL and ganglion thinning. Each patient had several Cirrus OCT and OCT-A scans taken of the posterior pole. The OCT-A en-face images demonstrated specific patterns of superficial capillary dropout. The appearance of superficial plexus capillary dropout in one case of glaucoma is contrasted against two cases of retinal ischemia. Early glaucoma appears to be associated with incomplete capillary bed dropout that extends from macular regions to the disc in a wedge- or arc-shaped pattern. Diabetic retinal ischemia appears to be associated with well-defined patchy and polygonal pockets of complete capillary bed obliteration that may not extend back to the disc. If an RNFL deviation map is superimposed over the superficial plexus en-face montage, areas of RNFL loss may correlate with and thus be well accounted for by areas of retinal ischemia in cases with RNFL thinning likely from ischemia. This approach may supplement inspection of OCT B-scans for focal retinal thinning when trying to differentiate RNFL and ganglion cell loss from retinal ischemia versus glaucoma in patients with diabetes. Formal research studies are needed to validate our observations and proposed use of OCT-A together with OCT in these patients.

Comparison of focal loss volume, global loss volume, retinal nerve fiber layer thickness, and corneal epithelial thickness in eyes with glaucoma and suspicious optic discs

Abstract: PURPOSE: The purpose of this study was to study the role of the focal loss volume (FLV), global loss volume (GLV), and other spectral-domain optical coherence tomography (SD-OCT) parameters in early diagnosis of glaucomatous damage. METHODS: A retrospective study included records of 34 eyes with early glaucoma (Group A) and 17 eyes with suspicious optic discs (Group B). Retinal nerve fiber layer (RNFL), ganglion cell complex (GCC), and corneal thickness parameters were assessed by the SD OCT (RTVue SD-OCT). These included the FLV, GLV, in addition to RNFL thickness, cup/disc ratio, GCC thickness, and anterior segment OCT for assessment of central corneal thickness and central corneal epithelial thickness. Data from both groups were subjected to statistical analysis. RESULTS: The FLV and GLV had the highest areas under the receiver operating characteristic curve in Group A eyes. FLV had higher (97.2%) specificity and was the earliest parameter to be affected by glaucomatous damage, followed by GLV. Moreover, Group A eyes had significant thinning of the RNFL (91.59 μm) compared to Group B (118.18 μm), and GCC thickness was also significantly thinner in Group A (92.07 μm) than in Group B (110.54 μm). Interestingly, Group A eyes had thinner corneal epithelium (nonsignificant) than Group B. CONCLUSION: FLV and GLV were of the greatest value in the assessment of early glaucomatous GCC degeneration.

Correlation between Structural and Functional Changes in Patients with Raised Intraocular Pressure Due to Graves' Orbitopathy.

This study explores the complication of secondary intraocular pressure (IOP) elevation and consequent glaucoma development in Graves' orbitopathy (GO), an autoimmune disorder associated with hyperthyroidism. Utilizing Octopus 900 visual field testing and optical coherence tomography (OCT), the research established correlations between functional and structural changes in optic nerve regions in patients with GO and patients with GO with elevated IOP (GO IOP) groups. A comparison with primary open-angle glaucoma (POAG) was conducted in a cohort of 182 subjects. The study identifies optic nerve head parameters that effectively differentiate changes in GO and GO IOP groups. In the GO group, the strongest correlation between structural and functional changes was observed in sector 7, while in the GO IOP group, it was in sectors 1 and 7. For POAG, correlation was found in six sectors. Elevated IOP in GO correlates with structural and functional impairments similarly to early glaucoma. Risk factors for GO-related elevated IOP included older age, longer duration of thyroid disease, and higher anti-thyroglobulin values. The study highlights the significance of regular IOP measurements, visual field assessments, and OCT examinations in GO patients. Early antiglaucoma intervention is warranted when characteristic structural and functional changes and/or risk factors are identified.

Surgical Outcomes of Early Versus Late Onset Glaucoma Associated With Sturge-Weber Syndrome.

Long-term intraocular pressure control can be difficult to achieve in eyes with Sturge-Weber syndrome glaucoma. The most commonly performed primary surgery was trabeculotomyin early onset disease and tube shunt implantation in late onset disease. To compare long-term surgical outcomes of glaucoma associated with Sturge-Weber syndrome (SWS) in eyes with early and late-onset disease. Medical records of children with glaucoma associated with SWS who underwent surgical treatment between January 1990 and December 2018 were reviewed. Those diagnosed ≤2 years of age were categorized as early onset while those who were diagnosed >2 years of age were late onset. Failure was defined as intraocular pressure (IOP) >21mm Hg or reduced <20% below baseline on 2 consecutive follow-up visits after 3 months, IOP ≤5mm Hg on 2 consecutive follow-up visits, reoperation for glaucoma or a complication, or loss of light perception. Forty-three eyes of 36 children were studied, including 26 eyes in the early-onset group and 17 eyes in the late-onset group. The early-onset group more frequently presented with buphthalmos, corneal edema, and Haab striae, while late-onset group had higher baseline IOP, larger cup-to-disc ratio, and longer axial length. The most commonly performed primary surgery was trabeculotomy (50%) in early-onset group and tube shunt implantation (71%) in late-onset group. The cumulative probability of failure after 5 years follow-up was 50.6% in early-onset group and 50.9% in the late-onset group ( P =0.56). Postoperative complications occurred in 3 eyes (12%) in early-onset group and 11 eyes (65%) in late-onset group ( P <0.001). Early and late-onset SWS glaucoma may represent 2 entities with different pathogenetic mechanisms, clinical presentations, primary surgical choices, and outcomes, though this needs corroboration in future studies.

Quantitative Measurement and Analysis of the Radial Peripapillary and Central Macular Microvasculature Density in Early Open-Angle Glaucoma Using OCT Angiography

Background Glaucoma is a prevalent cause of visual impairment, and early detection is critical to prevent progressive vision loss. Optical coherence tomography angiography (OCT-A) enables visualization of retinal and optic nerve microvasculature and holds promise for early glaucoma detection. Aims This study aims to assess microvasculature density alterations in glaucoma using OCT-A. Methods An observational cross-sectional case–control study was conducted at Benghazi Eye Hospital in Libya from December 2022 to August 2023. It included 160 eyes of 126 patients diagnosed with primary open-angle glaucoma and 120 eyes of 96 control subjects. OCT-A was performed using the Swept-Source OCT DRI Triton. Vessel density measurements were obtained from OCT-A images using new built-in software within the device. The data presented as mean ± standard deviation and percentages were analyzed using SPSS. The statistical significance of the differences between different groups was determined using independent t-tests, and the level of significance was set at p-value less than 0.05. Results OCT-A demonstrated significantly reduced microvasculature density in glaucoma eyes across all optic nerve sectors including the inferior (29.0%), superior (25.2%), central (23.5%), nasal (9.9%), and temporal sectors (9.3%; p &lt; 0.02). Moreover, glaucoma patients exhibited a significant reduction in vessel density in the superior macula (17% reduction), the temporal (15.7%,), nasal (12.9%), and inferior sectors (12.6%) (p &lt; 0.002). No statistical difference was seen with vessel density of the central sector (0.49%, p &gt;0.05). Conclusion OCT-A demonstrated significant reductions in microvasculature density in glaucoma patients compared with healthy controls. These findings support the association between glaucoma and vascular changes. Additionally, the TOPCON Swept-Source OCT DRI Triton new software shows promise as a valuable tool for early detection and monitoring of glaucoma-related vascular changes.

Hemifield-based analysis of pattern electroretinography in normal subjects and patients with preperimetric glaucoma

This prospective cross-sectional study investigated the visual function of preperimetric glaucoma (PPG) patients based on hemifield (HF) pattern electroretinogram (PERG) amplitudes. Thirty-two (32) normal subjects and 33 PPG patients were enrolled in control and PPG groups, respectively. All of the participants had undergone full ophthalmic examinations, including spectral-domain optical coherence tomography (SD-OCT), visual field (VF) examination and pattern electroretinography (PERG). The PERG parameters along with the HF ratios of SD-OCT and PERG were compared between the control and PPG groups. Pairwise Pearson's correlation coefficients and linear regression models were fitted to investigate the correlations. The PERG N95 amplitudes were significantly lower in the PPG group (P < 0.001). The smaller/larger HF N95 amplitude ratio of the PPG group was found to be smaller than that of the control group (0.73 ± 0.20 vs. 0.86 ± 0.12; P = 0.003) and showed positive correlations with affected HF average ganglion cell-inner plexiform layer (GCIPL) thickness (r = 0.377, P = 0.034) and with average GCIPL thickness (r = 0.341, P = 0.005). The smaller/larger HF N95 amplitude ratio did not significantly change with age (β = − 0.005, P = 0.195), whereas the full-field N95 amplitude showed a negative correlation with age (β = − 0.081, P < 0.001). HF analysis of PERG N95 amplitudes might be particularly useful for patients with early glaucoma.

Evaluation of corneal densitometry values with Pentacam in cases of ocular hypertension and pseudoexfoliative glaucoma

BackgroundExamination of corneal densitometry measurements using the Pentacam Scheimpflug imaging system in cases of pseudoexfoliative glaucoma (PEXG) and ocular hypertension (OHT). MethodsThe study included 50 eyes of 29 PEXG patients, 25 eyes of 16 OHT patients, and 76 eyes of 38 healthy control subjects followed in the glaucoma clinic. Corneal densitometry values of all cases were measured using the Scheimpflug imaging system (Pentacam, Oculus, Germany). Corneal densitometry was assessed based on 4 concentric radial zones (0–2 mm, 2–6 mm, 6–10 mm, and 10–12 mm) and depths (anterior, central, posterior, and total) within the Scheimpflug imaging system. The results were statistically analyzed. ResultsCorneal densitometry values examined between the OHT and control groups were higher in OHT and statistically significant (p < 0.05). Corneal densitometry values examined between the PEXG and control groups were higher in PEXG and statistically significant (p < 0.05). In comparison between the PEXG and OHT groups, corneal densitometry values in the central 0–2 mm, 2–6 mm, and 6–10 mm; posterior 0–2 mm and 2–6 mm radial zones were higher in PEXG and statistically significant (p < 0.05). ConclusionsIt was observed that elevated intraocular pressure levels in OHT cases could lead to changes in the cornea, consequently increasing corneal densitometry values. The higher corneal densitometry values in PEXG cases compared to OHT were attributed to the accumulation of pseudoexfoliative material in the cornea. Based on our study, corneal densitometry could serve as a potential biomarker for early glaucoma detection in OHT cases and could be employed to assess corneal transparency during the follow-up of PEXG cases.

Novel Methods for Diagnosing Glaucoma: Segmenting Optic Discs and Cups using Ensemble Learning Algorithms and CDR Ratio Analysis

Glaucoma, a multifactorial group of eye diseases characterized by progressive damage to the Glaucoma, a group of progressive optic neuropathies, is a leading cause of irreversible blindness globally, affecting millions of individuals. This research addresses the critical task of glaucoma identification through the segmentation of the optic disc and optic cup using ensemble learning algorithms, Unet and Gnet. The study leverages the capabilities of these algorithms to enhance the accuracy of the segmentation process, a crucial step in early glaucoma detection. A meticulously curated dataset of ophthalmic images is utilized, with a focus on preprocessing techniques includes resizing, normalization, filtering and contrast enhancement process to optimize the input quality. The proposed architectures of Unet and Gnet, highlighting their suitability for segmenting the optic disc and cup. The experimental setup involves rigorous training, with an emphasis on fine-tuning the models for segmentation tasks. Evaluation metrics, including Dice coefficient and sensitivity, are employed to assess the precision of the segmentation results. The outcomes demonstrate the efficacy of ensemble Unet and Gnet. Consistently achieving accuracy levels surpassing 98.90% across various datasets, the suggested model demonstrates exceptional performance in accurately categorizing severe cases. The study concludes with insights into the potential clinical impact of improved optic disc and cup segmentation on early glaucoma diagnosis, emphasizing the significance of ensemble learning in advancing ophthalmic image analysis for medical applications.

Accuracy of Bruch’s membrane opening minimum rim width and retinal nerve fiber layer thickness in glaucoma diagnosis depending on optic disc size

Background/aimThe aim of this paper is to compare retinal nerve fiber layer thickness (RNFL) and Bruch’s membrane opening-based minimum rim width (BMO-MRW) in terms of their performance in detecting early and moderate/advanced glaucoma using receiver operating characteristics (ROC) analysis and the classification using the 5th percentile as a cut-off.MethodsOne hundred eyes from 100 patients with early glaucoma (mean deviation (MD): < -5.0 dB) and 100 eyes from 100 patients with moderate/advanced glaucoma (MD: > -5.0 dB) were carefully matched to healthy controls based on optic disc size. Then, the dataset was divided, based on the 50th percentile of the measured Bruch’s membrane opening area (BMO-A), into small (BMO-A < 1.95 mm2) and large optic discs (BMO-A > 1.95 mm2). Finally, the discriminative performance of BMO-MRW and RNFL between glaucoma and controls using ROC analysis and the manufacturer’s classification based on the 5th percentile was analyzed.ResultsIn discriminating between glaucoma and matched healthy controls, global BMO-MRW and global RNFL thickness had comparable areas under the ROC curve for eyes with early glaucoma and both small BMO-As (ROC ± confidence interval [CI] 0.91 [0.87 to 0.95] and 0.88 [0.83 to 0.93]) and large BMO-As (0.86 [0.82 to 0.92] and 0.84 [0.79 to 0.90]), as well as in moderate/advanced glaucoma with small BMO-As (0.99 [0.98 to 1.00] and 0.97 [0.95 to 1.00]) and large BMO-As (0.94 [0.91 to 0.98] and 0.97 [0.94 to 1.00]). Using the calculated 5th percentile as a threshold value, the sensitivities for the detection of early and moderate/advanced glaucoma were comparable for BMO-MRW and RNFL in eyes with small optic discs (early glaucoma: fifty-two percent and 61%; moderate/advanced glaucoma: ninety-one percent and 92%). In eyes with large optic discs, the sensitivity of BMO-MRW was inferior to that of RNFL for both early (38% versus 51%) and moderate/advanced (80% versus 91%) glaucoma.ConclusionBased on an ROC analysis, the discriminative performance of BMO-MRW and RNFL between patients with early and moderate/advanced glaucoma and a healthy control group matched based on optic disc size is comparable in eyes with BMO-As smaller and larger 1.95 mm2. Using a classification based on the 5th percentile, as used in clinical practice, RNFL is shown to be superior to BMO-MRW regarding sensitivity in glaucoma detection with large optic discs. This study underscores the importance of RNFL imaging and measurement in the diagnostic evaluation of glaucoma, especially in cases of large optic discs.

Frontloading visual field tests detect earlier mean deviation progression when applied to real-world-derived early-stage glaucoma data.

To examine the diagnostic accuracy of performing two (frontloaded) versus one (clinical standard) visual field (VF) test per visit for detecting the progression of early glaucoma in data derived from clinical populations. A computer simulation model was used to follow the VFs of 10,000 glaucoma patients (derived from two cohorts: Heijl etal., Swedish cohort; and Chauhan etal., Canadian Glaucoma Study [CGS]) over a 10-year period to identify patients whose mean deviation (MD) progression was detected. Core data (baseline MD and progression rates) were extracted from two studies in clinical cohorts of glaucoma, which were modulated using SITA-Faster variability characteristics from previous work. Additional variables included follow-up intervals (six-monthly or yearly) and rates of perimetric data loss for any reason (0%, 15% and 30%). The main outcome measures were the proportions of progressors detected. When the Swedish cohort was reviewed six-monthly, the frontloaded strategy detected more progressors compared to the non-frontloaded method up to years 8, 9 and 10 of follow-up for 0%, 15% and 30% data loss conditions. The time required to detect 50% of cases was 1.0-1.5 years less for frontloading compared to non-frontloading. At 4 years, frontloading increased detection by 26.7%, 28.7% and 32.4% for 0%, 15% and 30% data loss conditions, respectively. Where both techniques detected progression, frontloading detected progressors earlier compared to the non-frontloaded strategy (78.5%-81.5% and by 1.0-1.3 years when reviewed six-monthly; 81%-82.9% and by 1.2-2.1 years when reviewed yearly). Accordingly, these patients had less severe MD scores (six-monthly review: 0.63-1.67 dB 'saved'; yearly review: 1.10-2.87 dB). The differences increased with higher rates of data loss. Similar tendencies were noted when applied to the CGS cohort. Frontloaded VFs applied to clinical distributions of MD and progression led to earlier detection of early glaucoma progression.

XEN-45 in the management of early glaucoma surgery: A national Delphi consensus study

Background and objectiveRecommendations on general glaucoma management and the use of early minimally invasive and microincisional surgeries are limited. This study aimed to establish consensus regarding glaucoma management, focusing on the XEN-45 gel stent implant. MethodsA Delphi consensus-driven process was used. The scientific committee led the study, identified the expert panel, and participated in elaborating the questionnaire. Fifty-one panelists were invited to complete, on a nine-point Likert scale, an 89-item questionnaire covering three topic blocks. Two Delphi rounds were performed. Consensus was achieved if ≥66.6% of panelists reached agreement or disagreement. ResultsPanelists agreed on 84 items related to the patients’ quality of life, the therapeutic algorithm and patient profile, and surgical and pre- and post-operative management. Panelists agreed on the suitability of XEN stent implants to treat glaucoma at different stages and for different patient profiles: young patients, elderly or with significant comorbidities, and with myopic glaucoma, patients who failed previous surgeries, and with previous poor post-operative experience. XEN surgery was considered a therapeutic step prior to classic filtering surgery and a possible first surgical option in elderly patients with comorbidities and uncontrolled intraocular pressure. XEN surgery allows the patient to return to routine daily activities faster than conventional filtering surgeries and to reduce and/or eliminate topical treatments. ConclusionsThis Delphi-driven consensus resulted in a series of general recommendations for glaucoma management, including those related to patient quality of life, therapeutic algorithm, and patient profile, and specific ones regarding the use of XEN stent gel surgery.

Treatment Outcomes of Primary Combined Trabeculotomy With Trabeculectomy in Early Onset Glaucoma With Sturge-Weber Syndrome.

In eyes with Sturge-Weber syndrome (SWS) with early onset glaucoma, primary combined trabeculotomy with trabeculectomy (CTT) had a good intermediate-term success rate and minimal postoperative complications. Retrospective cohort study. To report the intermediate-term outcomes of primary CTT in early onset glaucoma with SWS. This study included 49 eyes of 49 children (1997-2020) with SWS and early onset glaucoma who underwent primary CTT with at least 1-year postoperative follow-up. Success was defined as complete when intraocular pressure was >5mm Hg and ≤16mm Hg under general anesthesia or ≤21mm Hg in the clinic without antiglaucoma medications (AGMs) and as qualified with AGM. The median age (interquartile range) at CTT was 0.58 (0.19, 8.3) years. The median postoperative follow-up was 4.7 years (2.5, 9). The majority were male children (31/49, 63%). Epilepsy was noted in 7 (14.3%) and diffuse choroidal hemangioma in 17 children (35%). At diagnosis, 37 eyes(75%), had corneal edema, and the mean (±SD) horizontal corneal diameter was 12.8 ± 0.7mm. Postoperatively, the median intraocular pressure decreased from 26 (22, 30) mm Hg to 16 (12, 20) mm Hg ( P < 0.0001) and the median number of AGM reduced from 1 (0,1) to 0 (0,1; P < 0.01). Complete success probability of CTT was 86% (76, 96) at 1 year and 64% (49, 84) at 5 years. Qualified success was 98% (94, 100) at 1 year and 89% (78, 100) at 5 years. A larger cup-to-disk ratio ( P < 0.005) was associated with a higher risk of surgical failure. Postoperative complications were noted in 9 eyes (18%), all resolved with conservative management except one eye with a retinal detachment that ended in phthisis bulbi. CTT as a primary procedure showed good long-term efficacy and safety in SWS with early onset glaucoma.

Short-term report of early glaucoma surgery with a clear lens extraction and an intraocular lens, OMNI canaloplasty, and a HYDRUS microstent: a case series in younger patients.

The purpose of this case series is to report the surgical outcomes from the combination of a clear lensectomy, OMNI® canaloplasty, and a HYDRUS® microstent with an adjacent goniotomy. This is a retrospective non-comparative single-center case series of four black patients of African descent with glaucoma who were treated with a clear lensectomy, OMNI canaloplasty, and a HYDRUS microstent with an adjacent goniotomy. The surgeries were performed by an experienced cataract and glaucoma surgeon, Daniel Laroche, MD. The parameters investigated in this study were postoperative intraocular pressure (IOP) and the mean number of preoperative and postoperative medications needed. The mean age of the four patients was 44.5 years. All patients had a mean postoperative reduction in IOP of 17 mmHg to 12.7 mmHg. The mean number of preoperative medications was 2.2, while the mean number of postoperative medications was 0.3. Potential complications such as hyphema, IOP spikes, or corneal edema were not seen in this series. All patients achieved a lower IOP and stable vision with less refractive error. Patients also experienced improved visual fields, clearer vision, and more open angles. Clear lensectomy and combined microinvasive glaucoma surgery (MIGS) in patients with primary open-angle glaucoma (POAG) and narrow-angle glaucoma (NAG) results in the safe lowering of IOP. The limitations of this study include the small series size and the retrospective potential for bias. Further research with a larger series and a prospective trial with follow-up should be performed.

New methods for detection of early loss of rapid flicker, spatial vision, and chromatic sensitivity in glaucoma

Purpose: To examine whether ocular hypertension and early glaucoma cause measurable changes in spatial vision, rapid flicker sensitivity and red/green and yellow/blue colour vision.Methods: We examined subjects aged 40 to 78 years with ocular hypertension (OHT), primary open angle glaucoma (POAG), normal tension glaucoma (NTG), and age matched controls. Monocular best corrected visual acuity (BCVA) was tested using EDTRS charts.VA and Functional Contrast Sensitivity (FCS) with Landolt ring stimuli of both positive and negative contrast were also measured monocularly with the Acuity‐Plus test. Red/green (RG) and yellow/blue (YB) colour thresholds were measured with the Colour Assessment and Diagnostics (CAD) test. Photopic (cone‐enhanced) and mesopic (rod‐enhanced) rapid flicker thresholds were measured at the fovea (0°) and at an eccentricity of 5° in each of the four quadrants using the Flicker‐Plus test. All subjects had their visual fields measured using the Humphrey visual field analyser (24–2 SITA standard protocol). Peripapillary retinal nerve fibre layer thickness (pRNFLT) and macular retinal layer thicknesses were measured using the Heidelberg Spectralis OCT.Results: The mean, logMAR BCVA for OHT patients was 0.00 and for POAG and NTG patients was −0.10 and 0.10, respectively. For control participants, mean logMAR BCVA was 0.00. Mean pRNFL thickness was significantly reduced for glaucoma patients (59.5 ± 7.7 μm) as compared to control subjects (94.6 ± 5.13 μm) and OHT patients (115.5 ± 3.5 μm). POAG and NTG patients showed significantly higher colour thresholds (mean red/green threshold 4.97, blue/yellow 5.28 CAD units) compared to control subjects (mean red/green threshold 2.07, blue/yellow 1.62 CAD units). One OHT patient showed acquired loss of blue/yellow colour vision (3.23 CAD units), with normal VA. The Acuity‐Plus test which employs briefly presented stimuli, also revealed significant loss of VA (3.78 and 3.64 min of arc) and FCS (141.32% and 100%) in an NTG patient, with results outside normal limits for both positive and negative contrast, respectively. Central FCS was higher and outside the normal age limits for POAG patients (73.41% and 89.27%) as compared to age matched controls (61.27% and 33.63%). OHT patients, on the other hand, produced FCS thresholds within normal limits. Flicker modulation thresholds were higher for both rod and cone enhanced stimulus conditions in glaucoma and OHT patients, when compared to control subjects.Conclusion: The results reveal non‐uniform, losses that can affect selectively each of the visual attributes examined in this study. These preliminary findings suggest that in addition to VA and FCS tests, colour vision and rapid flicker sensitivity should also be examined in patients with optic nerve pathologies like glaucoma.