Glaucomatous Defects Research Articles

Predicting Visual Field Progression by Optical Coherence Tomography Angiography and Pattern Electroretinography in Glaucoma.

Reduced P50-N95 amplitude on pattern electroretinography (PERG) and the presence of microvasculature dropout (MvD) on optical coherence tomography angiography (OCT-A) at baseline were significant factors associated with visual field (VF) progression in predominantly normal tension glaucoma (NTG) patients. We investigated the baseline demographics and ocular characteristics that predict future progression in glaucoma patients, including PERG and OCT-A parameters. One Hundred forty eyes with open angle glaucoma that were prospectively enrolled and followed up for at least 3 years, and underwent at least 5 serial VF tests were included. Baseline PERG was performed, and N35, P50, and N95 latencies and amplitudes were obtained. Superficial vessel density at the macula and complete loss of microvasculature within the deep retinal layer of the parapapillary region (MvD) were evaluated from baseline OCT-A images. Eyes with a glaucomatous VF defect in either both hemifields within 24 points of a central 10 degrees of fixation, and with no VF abnormality in the nasal periphery outside 10 degrees of fixation, were considered to have isolated central scotoma. During follow-up, detected disc hemorrhage (DH) was recorded. Parameters associated with VF progression were determined using linear regression analysis of the mean deviation (MD) values, in combination with an event-based analysis using the Glaucoma Progression Analysis (GPA) software from the Humphrey Field Analyzer. "Likely progression" using GPA was considered to have glaucoma progression. Of the 140 eyes, 107 (76.4%) were NTG and 57 (40.7%) exhibited glaucoma progression as defined by Humphrey VF GPA. The MD slopes were -0.43±1.11dB/y in the progressors and 0.59±1.27dB/y in the nonprogressors ( P <0.001). Glaucoma patients with progression showed frequent MvD on OCT-A, isolated central scotoma, frequent DH, and reduced baseline P50-N95 amplitude compared with patients without progression. Age at diagnosis ( P =0.038) and baseline P50-N95 amplitude ( P =0.019) showed significant associations with the MD slope. The presence of MvD on OCT-A ( P <0.001) and baseline P50-N95 amplitude ( P =0.037) were significantly associated with VF progression on GPA. The presence of MvD and retinal ganglion cell dysfunction by PERG at baseline, DH or central scotoma were significant factors associated with VF progression in predominantly NTG patients. These patients should be monitored more closely.

Effect of a patient educational video on visual field test reliability

Purpose: Standard automated perimetry (SAP) is the gold standard for detecting and monitoring visual field (VF) defects in glaucoma, but frequent re-testing due to unreliable results increase the burden on this frequently used service. This study aims to assess the reliability of the Humphrey visual field (HVF) test in glaucoma-suspect patients with no previous SAP experience and to determine the effect of a VF test educational video on reliability.Study design: The study was conducted as a full cycle audit.Methods: The audit cycle was carried out in four phases: pre-intervention audit, intervention, monitoring, and post-intervention audit. The pre-intervention audit was carried out from January 2020 to May 2020 and the post-intervention audit was carried out from September 2020 to December 2020. The intervention was in the form of a VF test educational video. A post-video assessment pertaining to the contents of the video was given to patients in the intervention group to complete after they watched the video. The results were then tabulated and analysed.Results: The pre-intervention audit showed that only 66.7% of glaucoma-suspect patients with no previous SAP experience had reliable HVF tests. Post-intervention, HVF reliability improved to 87.5% of patients. Based on the reliability parameters, the main reason for the HVF test being classified as unreliable in both the pre- and post-intervention was fixation loss greater than 20% in 36 (90%) and 11 (73.3%) patients, respectively. There were 76.9% of patients with unreliable fields who had &lt; 4 correct answers on the post-video assessment; all patients who had &gt; 4 correct answers had reliable HVF results.Conclusion: HVF reliability performance in glaucoma-suspect patients improved with the introduction of a pre-test educational video. It is a simple and inexpensive method which may reduce the need for repeat HVF tests for those with unreliable tests.

Comparison between frequency-doubling technology perimetry and standard automated perimetry in early glaucoma

This study aimed to find out the significance of the difference between frequency-doubling technology perimetry (FDT) and standard automated perimetry (SAP) in terms of the detected visual field (VF) damage, and evaluate associated factors to SAP–FDT difference in early glaucoma. Glaucoma patients in early stage (MD better than − 6.0 decibel, 96 eyes) were included in this cross-sectional study. We subtracted mean deviation (MD) and pattern standard deviation (PSD) of FDT from those of SAP, respectively. Additionally, we counted significantly depressed points of P < 5% and P < 1% on the pattern deviation probability plot of both FDT and SAP and defined eyes with significant SAP–FDT difference when the number of abnormal points were greater than 4 points on FDT. We measured lamina cribrosa depth (LCD) and lamina cribrosa curvature index (LCCI) for structural parameters of the optic nerve head from images using enhanced depth imaging of the optical coherence tomography (OCT). Peripapillary vessel density (VD) and presence of microvasculature dropout (MvD), the complete loss of choriocapillaris in localized regions of parapapillary atrophy, was evaluated using deep layer map of OCT angiography (OCT-A) for vascular parameters. Peripheral nasal step (PNS) group had an isolated glaucomatous VF defect within nasal periphery outside 10° of fixation. Parafoveal scotoma (PFS) group had an isolated glaucomatous VF defect within 12 points of a central 10˚ radius. Eyes with significant SAP–FDT difference showed higher detection of MvD on deep layer map of OCT-A, greater LCD, and greater LCCI (all P < 0.05, respectively). In logistic regression analysis, frequent presence of MvD, less presence of disc hemorrhage, and greater LCD were significantly associated with significant SAP–FDT difference. Sub-analysis was performed in eyes with PNS (50 eyes) and PFS (46 eyes). SAP–FDT difference of MD value showed positive association with peripapillary VD on deep layer of OCT-A, which was significant in eyes with PFS compared to eyes with PNS. SAP–FDT difference of PSD value showed negative association with LCCI and LCD, which was significant in eyes with PNS compared to eyes with PFS. Glaucomatous eyes classified by the difference of the detected VF damage on FDT versus SAP showed different clinical features. Greater SAP–FDT difference was significantly associated with structural parameters such as LCD and LCCI. Less SAP–FDT difference was associated with presence of disc hemorrhage and lower deep layer peripepillary VD. There is possibility to use the difference of SAP and FDT to identify associated risk factors in glaucoma patients.

Comparison of the Structure-Function Relationship Between Advanced Primary Open Angle Glaucoma and Normal Tension Glaucoma.

The aim was to investigate and compare the characteristics of visual field (VF) defects in primary open angle glaucoma (POAG) and normal-tension glaucoma (NTG) with advanced glaucomatous damage and to determine whether the structure-function relationships found in advanced glaucoma differ based on their glaucoma classification. Ninety-seven eyes of 97 patients (59 eyes with POAG and 38 eyes with NTG) with advanced glaucoma were included in this cross-sectional study. Scores at each test point of the 30-2 VF total deviation map were recorded, and average values at each test point were point-wise compared between the groups. Peripapillary retinal nerve fiber layer (RNFL) and macular thickness (total, RNFL, ganglion cell layer, and inner plexiform layer thickness) were measured. The structure-function relationship based on the map of Garway-Heath was determined and compared between the 2 groups. At advanced stage of glaucoma, POAG eyes demonstrated more diffusely distributed VF defects, whereas NTG eyes had more severe VF defects at the superior nasal quadrant, showing increased asymmetry. Overall, peripapillary RNFL, macular ganglion cell layer, and macular inner plexiform layer thickness showed good relationships with 30-2 VF parameters in both groups. However, in total macula and macular RNFL thickness, the structure-function relationships tended to show different characteristics depending on the glaucoma classification; NTG eyes showed overall better relationships. In advanced glaucoma, differences in patterns of VF damage were found between POAG and NTG eyes. Conventional peripapillary RNFL and macular measurements showed generally good performance for estimating functional status, particularly in NTG eyes.

A Global and Sector-Based Comparison of OCT Angiography and Visual Field Defects in Glaucoma.

Purpose To evaluate the correlation of optical coherence tomography angiography (OCTA) and spectral-domain optical coherence tomography (SD-OCT) with visual field for global and sector-based indices among glaucoma and glaucoma-suspected eyes. Patients and Methods. This is a retrospective study, and in total, 48 glaucoma eyes and 31 glaucoma suspect eyes were included. The correlation between visual field parameters and radial peripapillary capillary (RPC) vessel density via OCTA was compared to the correlation with retinal nerve fiber layer (RNFL) thickness via SD-OCT. The RPC vessel density and RNFL thickness were divided into eight sectors, which included the temporal upper, temporal lower, superotemporal, inferotemporal, superonasal, inferonasal, nasal upper, and nasal lower sectors. Pearson correlations with 95% confidence intervals were calculated with resampling, and correlations were compared with a Fisher Z transformation. Results Both RPC vessel density (R = 0.63, 95% CI [0.24, 0.86]) and RNFL thickness (R = 0.49, 95% CI [0.23, 0.69]) were correlated with the mean deviation when comparing global indices of glaucoma patients. In glaucoma suspects, the correlations between the mean deviation and RPC vessel density (R = 0.21, 95% CI [−0.05, 0.49]) and RNFL thickness (R = 0.01, 95% CI [−0.35, 0.39]) were not significant. Glaucoma eyes had the highest correlation between the mean sensitivity and RPC vessel density and RNFL thickness for the superotemporal, superonasal, temporal upper, and inferotemporal sectors. Conclusion Across a diverse population and heterogeneous glaucoma types, RPC vessel density measurements correlate with global and sector-wise visual field indices similar to RNFL thickness.

The "Topography" of Glaucomatous Defect Using OCT and Visual Field Examination.

AimTo describe the modifications in the superior and inferior retinal nerve fiber layer (RNFL) thickness regarding the distribution of the VF defects for the horizontal meridians in glaucomatous patients and the differences in the RNFL thickness topography between glaucomatous and healthy subjects.MethodsOne hundred twenty eyes of 91 patients affected by glaucoma and 94 eyes of 51 normal patients were retrospectively reviewed. Computerized 30°VF (Octopus G1 Dynamic strategy) and optical coherence tomography (OCT) ONH and 3D disk analysis were performed in all cases. The RNFL thickness measures analyzed in both groups were superior-nasal (SN), superior-temporal (ST), inferior-nasal (IN), and inferior temporal (IT) sectors. The VFs were classified according to the distribution of the VF defect as for the horizontal meridian in the pattern deviation plot as superior, inferior, predominantly superior, or predominantly inferior.ResultIn the glaucomatous group, 78 eyes (65%) showed a predominantly superior VF defect, while 38 eyes (32%) showed a predominantly inferior VF defect. Fifty-six eyes (46.7%) presented an exclusively superior, and 27/120 eyes (22.5%) presented an exclusively inferior VF defect. In the control group, the thickest RNFL sector was IT. The ST sector showed the thickest RNFL in presence of an exclusive superior VF defect. In case of an exclusive inferior VF defect, the thickest RNFL was the IT sector. VF showing superior defect presented a more altered MD than the VF with an inferior defect.ConclusionGlaucomatous damage affects both the superior and inferior neural rim almost simultaneously. However, the neural rim loss seems to be asymmetric, involving the inferior or superior rim depending on the predominant involvement of the superior or inferior hemifield at the VF test. Particularly, the IT sector appears to be the most compromised in glaucomatous eyes. Therefore, the asymmetry between superior and inferior RNFL could support the diagnosis of glaucoma.How to cite this articlede Paula A, Perdicchi A, Pocobelli A, et al. The “Topography” of Glaucomatous Defect Using OCT and Visual Field Examination. J Curr Glaucoma Pract 2022;16(1):31-35.

Screening of high myopia patients for association with primary open angle glaucoma.

Objectives: To review the prevalence of primary open angle glaucoma in patients with high myopia. Study Design: Observational Study. Setting: Department of Ophthalmology, KDA Teaching Hospital Kohat. Period: January 2019 to December 2019. Material &amp; Methods: During this period 93 high myopic patients were selected. Informed consents were taken from them after explaining the purpose, procedure and tests required for diagnosis. Out of 93 patients 74 were male and 19 were female. Age range of the patients was from 20 to 57 years with mean age 43 years. Proper proforma was designed for documentation of intraocular pressure, perimetry, fundoscopy (Cup-disc ratio) and Optical coherence topography. Refraction of all patients was done with auto-refractometer and then subjectively. All 93 patients were high myopic with refractive error of -6 diopter spherical and above. Intraocular pressure was checked with air puff tonometer. Anterior segment examination was checked with slit lamp. Gonioscopy was done in 9 patients whose angles were suspected to be narrow or open. Pupils were dilated with tropicamide eye drops. Fundosopy with direct and indirect slit lamp biomicrosopy was done for Cupped-Disc ratio. 2 patients who had high intraocular pressure with no glaucomatous cupping disc were advised Optical coherence topography. Perimetry to all patients was advised with automated visual field analyzer. Results: Out of 93 high myopic patients 13(13.97%) had glaucomatous features. Out of 13 patients intraocular pressure more than 21mmHg and glaucomatous field defects were present in 100% while glaucomatous cupping discs were present in 11(84.61%) patients. Conclusion: High myopia is high risk association with primary open angle glaucoma.

Comparison of ZETA Fast (PTS) (Optopol Technology) and Humphrey SITA Fast (SFA) (Carl Zeiss Meditec) Perimetric Strategies.

Purpose To compare two threshold strategies for visual field assessment, ZETA Fast (Optopol Technology) and Humphrey SITA Fast (Carl Zeiss Meditec), in controls and subjects with glaucoma. Patients and Methods. A prospective case-control study was carried out in which the clinical practice study included 26 controls and 26 glaucoma subjects. Testing for each strategy was monocular. Quantitative comparisons of mean deviation (MD), pattern standard deviation (PSD), visual field index (VFI), and test duration were made using two one-sided t-tests and Wilcoxon signed-rank tests. Confusion matrices were constructed to assess Optopol's detection as a proxy for Zeiss's detection of early glaucomatous defects. Receiver operating characteristic (ROC) curves were used to assess MD and PSD's discriminability. Results The difference in MD values (Optopol-Zeiss) was within the margin for controls (difference = 0.36, p=0.06), but not for glaucomatous subjects (difference = 2.16, p=1.0). The Optopol strategy took longer than the Zeiss strategy in both controls (difference = 23 seconds, p=0.001) and glaucomatous subjects (difference = 49 seconds, p < 0.001). PSD values were higher and VFI values were lower from Optopol in glaucomatous subjects (p < 0.001 and p=0.002). Optopol was 92% sensitive in capturing early glaucomatous defects with MD <−2 when compared to Zeiss (p < 0.001). ROC analysis shows Optopol yields higher discriminability than Zeiss for MD/PSD indices. Conclusions Both strategies enable effective identification of glaucomatous defects within 6 minutes; they also offer high sensitivity with a high correlation in global indices between the two strategies. The Optopol strategy is an alternative to the Zeiss counterpart with the limitation of a marginally longer testing protocol but a higher sensitivity of detecting glaucomatous defects.

Archetypal Analysis Reveals Quantifiable Patterns of Visual Field Loss in Optic Neuritis.

PurposeIdentifying and monitoring visual field (VF) defects due to optic neuritis (ON) relies on qualitative clinician interpretation. Archetypal analysis (AA), a form of unsupervised machine learning, is used to quantify VF defects in glaucoma. We hypothesized that AA can identify quantifiable, ON-specific patterns (as archetypes [ATs]) of VF loss that resemble known ON VF defects.MethodsWe applied AA to a dataset of 3892 VFs prospectively collected from 456 eyes in the Optic Neuritis Treatment Trial (ONTT), and decomposed each VF into component ATs (total weight = 100%). AA of 568 VFs from 61 control eyes was used to define a minimum meaningful (≤7%) AT weight and weight change. We correlated baseline ON AT weights with global VF indices, visual acuity, and contrast sensitivity. For eyes with a dominant AT (weight ≥50%), we compared the ONTT VF classification with the AT pattern.ResultsAA generated a set of 16 ATs containing patterns seen in the ONTT. These were distinct from control ATs. Baseline study eye VFs were decomposed into 2.9 ± 1.5 ATs. AT2, a global dysfunction pattern, had the highest mean weight at baseline (36%; 95% confidence interval, 33%–40%), and showed the strongest correlation with MD (r = −0.91; P < 0.001), visual acuity (r = 0.70; P < 0.001), and contrast sensitivity (r = −0.77; P < 0.001). Of 191 baseline VFs with a dominant AT, 81% matched the descriptive classifications.ConclusionsAA identifies and quantifies archetypal, ON-specific patterns of VF loss.Translational RelevanceAA is a quantitative, objective method for demonstrating and monitoring change in regional VF deficits in ON.

Anatomic and refractional correlations in earliest glaucomatous visual field defects.

In glaucoma, initial visual field scotomas can be peripheral or central, whereas central scotomas are more severe and can disrupt daily activities. Individual anatomical features may influence the distribution of retinal nerve fibers and the starting site of visual field defects in glaucoma. In this study, we aimed to correlate myopia and hyperopia or anatomical variation of the disk-fovea angle with initial central or peripheral lesions in the visual field. This cross-sectional study included patients with primary open-angle glaucoma divided into a group of isolated central or peripheral scotomas in the visual field with MD > or equal to -6 dB, correlating with the degree of ametropia and anatomical variations, such as the disk-fovea angle. We included 52 patients with glaucoma. Of 20 myopic patients, 6 (30%) had central scotomas, and 14 (70%) had peripheral scotomas. Of 32 hyperopic patients, 12 (37.5%) had central scotomas, and 20 (63.5%) had peripheral scotomas. Regarding the disk-fovea angle, 25 eyes had the disk-fovea angle of < -7°, with 9 (36%) eyes presenting with central scotoma, and 27 eyes presented with the disk-fovea angle of > -7°, with 9 (33.3%) eyes presenting with a central scotoma. This study showed an association between ametropia and scotomas on the perimetry in patients with glaucoma. Patients had a higher incidence of peripheral scotomas, but hyperopic patients had a greater number of central scotomas than myopic patients, and myopic patients had more peripheral scotomas than hyperopic patients. The disk-fovea angle was not correlated with scotomas in initial glaucoma.

Point-wise variability of threshold sensitivity of 24-2 and 10-2 visual fields.

PURPOSE:To evaluate point-wise variability of threshold sensitivity at different test locations on 24-2 and 10-2 visual field (VF).MATERIALS AND METHODS:Electronic medical records of patients seen at a tertiary eye care center were screened to include those with at least 3 reliable VF with glaucomatous defects involving fixation on 24-2 and confirmed on 10-2 test strategy. Ninety eyes of 90 patients were categorized into 3 severity groups based on mean deviation (MD on 24-2) test strategy; MD<-6 dB and >-12 dB, <-12 dB and >-20 dB and <-20 dB and >-30 dB. Variability of threshold sensitivity at all topographical test locations in central (ring 1), mid-peripheral (ring 2), peripheral rings on 24-2 VF test strategy (ring 3), and central (ring 4) and paracentral (ring 5) on 10-2 VF test along with variability of visual field index and central field index were calculated by multilevel mixed effects model.RESULTS:Central ring1 on 24-2 and ring 4 on 10-2 showed higher variability (>10 dB) than peripheral ring 2, 3, and 5. Seventy-three eyes were adjudged as stable and 17 as progressing in this cohort. The average ring and point-wise variability was higher in stable eyes (2-6 dB) across all glaucoma severities. Across severity, variability was seen to decrease with increasing severity with minimal variability in point-wise threshold sensitivity beyond MD <-20 dB.CONCLUSION:Central test points/ring on 24-2 and 10-2 with greater threshold variability suggests that status of the eye, severity and topographical location of test points should be incorporated into conventional progression algorithms to predict true glaucoma progression.

Combining OCT and OCTA for Focal Structure–Function Modeling in Early Primary Open-Angle Glaucoma

PurposeTo investigate modeling of the focal visual field (VF) loss by combining structural measurements and vascular measurements in eyes with early primary open-angle glaucoma (POAG).MethodsIn this cross-sectional study, subjects with early glaucoma (VF mean deviation, ≥−6 dB) underwent optical coherence tomography (OCT) imaging, optical coherence tomography angiography (OCTA) imaging, and Humphrey 24-2 VF tests. Capillary perfusion densities (CPDs) were calculated after the removal of large vessels in the OCTA images. Focal associations between VF losses at the individual VF test locations, circumpapillary retinal nerve fiber layer (RNFL) thickness measurements from OCT, and CPDs were determined using nerve fiber trajectory tracings. Linear mixed models were used to model focal VF losses at each VF test location.ResultsNinety-seven eyes with early POAG (VF mean deviation, −2.47 ± 1.64 dB) of 71 subjects were included. Focal VF modeling using a combined RNFL–CPD approach resulted in a median adjusted R2 value of 0.30 (interquartile range [IQR], 0.13–0.55), whereas the RNFL-only and CPD-only approaches resulted in median values of 0.22 (IQR, 0.10–0.51) and 0.26 (IQR, 0.10–0.52), respectively. Seventeen VF locations with the combined approach had an adjusted R2 value greater than 0.50. Likelihood testing at each VF test location showed that the combined approach performed significantly better at the superior nasal VF regions of the eyes compared with the univariate approaches.ConclusionsModeling of focal VF losses showed improvements when structural thickness and vascular parameters were included in tandem. Evaluation of VF defects in early glaucoma may benefit from considering both RNFL and OCTA characteristics.

Analysis of Socioeconomic Factors Affecting Follow-Up in a Glaucoma Screening Program.

PurposeTo determine what socioeconomic factors affect follow-up in a glaucoma screening program.Patients and MethodsThis was a retrospective cohort study of six health fairs in South Florida from October 2012 to March 2013 among socially and economically disadvantaged populations. Visual acuity (VA), intraocular pressure (IOP), cup-to-disc ratio (CDR), and visual field testing were obtained to identify glaucoma suspects. Glaucoma suspects were defined as having intraocular pressure ≥24 mm Hg, cup-to-disc ratio of ≥0.6 in either eye, or glaucomatous defects on visual field testing. In July 2015, telephone surveys were administered to assess follow up and socioeconomic factors.ResultsSeventy-two out of 144 (50%) glaucoma suspects responded to the survey and were included in the analysis. Of the 72 respondents, average age was 52.8 years old and 65% were female. The most common race was African American (69%) and ethnicity was Haitian (51%). Glaucoma suspects who followed up were significantly more likely to have health insurance compared to those who did not follow up (74% vs 43%, p = 0.014). No significant difference in follow-up based on age (p = 0.125), education (p = 0.151), gender (p = 0.48), or ethnicity (p = 0.707) was identified. Of the 30 respondents, who did not follow up, the most common reasons were “no insurance” (57%, 17/30) and “not worried” (33%, 10/30).ConclusionInsurance was the main socioeconomic factor in determining whether glaucoma suspects followed up after community health screenings. Streamlining social services could increase clinical access of glaucoma suspects.

Vessel Density in the Macular and Peripapillary Areas in Preperimetric Glaucoma to Various Stages of Primary Open-Angle Glaucoma in Taiwan.

Peripapillary and macular vessel density (VD) are reduced in myopic non-glaucomatous eyes, the dynamic range of VD may be decreased by myopia, and whether VD measurement has the potential in differentiating stages of glaucoma severity in patients with myopic glaucoma remains questionable. This observational, cross-sectional study aimed to clarify the changes in peripapillary and macular VDs in preperimetric glaucoma (PPG) and primary open-angle glaucoma in the early, moderate, and late stages. A total of 1228 eyes from 661 participants (540 normal, 67 PPG, and 521 glaucomatous) were included. Participants underwent free blood tests at the internal medicine clinic to retrieve systemic data. Patients with glaucoma were grouped by disease severity, defined by glaucomatous visual field mean defect, including early-(224 eyes), moderate-(103 eyes), and late-stage glaucoma (194 eyes), and further divided into advanced (158 eyes) and terminal glaucoma (36 eyes). Macular VD, peripapillary VD, circumpapillary retinal nerve fiber layer (cpRNFL) thickness, and ganglion cell complex (GCC) thickness were evaluated and divided into superior and inferior parts. One-way analysis of variance was performed, followed by Tukey’s post-hoc test. The peripapillary VD was significantly different between the healthy and PPG groups and the early-, moderate-, and late-stage glaucoma subgroups (all p < 0.001). Peripapillary VD measurements are helpful in differentiating the various stages of glaucoma even in patients with myopic glaucoma.

Enhanced Objective Detection of Retinal Nerve Fiber Bundle Defects in Glaucoma With a Novel Method for En Face OCT Slab Image Construction and Analysis.

PurposeTo introduce and evaluate the performance in detecting glaucomatous abnormalities of a novel method for extracting en face slab images (SMAS), which considers varying individual anatomy and configuration of retinal nerve fiber bundles.MethodsDense central retinal spectral domain optical coherence tomography scans were acquired in 16 participants with glaucoma and 19 age-similar controls. Slab images were generated by averaging reflectivity over different depths below the inner limiting membrane according to several methods. SMAS considered multiple 16 µm thick slabs from 8 to 116 µm below the inner limiting membrane, whereas 5 alternative methods considered single summary slabs of various thicknesses and depths. Superpixels in eyes with glaucoma were considered abnormal if below the first percentile of distributions fitted to control data for each method. The ability to detect glaucoma defects was measured by the proportion of abnormal superpixels. Proportion of superpixels below the fitted first percentile in controls was used as a surrogate false-positive rate. The effects of slab methods on performance measures were evaluated with linear mixed models.ResultsThe ability to detect glaucoma defects varied between slab methods, χ2(5) = 120.9, P < 0.0001, with SMAS showing proportion of abnormal superpixels 0.05 to 0.09 greater than alternatives (all P < 0.0001). No slab method found abnormal superpixels in controls.ConclusionsSMAS outperformed alternatives in detecting abnormalities in eyes with glaucoma. SMAS evaluates all depths with potential retinal nerve fiber bundle presence by combining multiple slabs, resulting in greater detection of reflectance abnormalities with no increase in surrogate false positives.Translational RelevanceSMAS may be used to objectively detect glaucoma defects in en face optical coherence tomography images.

Unsupervised Machine Learning Identifies Quantifiable Patterns of Visual Field Loss in Idiopathic Intracranial Hypertension.

PurposeArchetypal analysis, a form of unsupervised machine learning, identifies archetypal patterns within a visual field (VF) dataset such that any VF is described as a weighted sum of its archetypes (ATs) and has been used to quantify VF defects in glaucoma. We applied archetypal analysis to VFs affected by nonglaucomatous optic neuropathy caused by idiopathic intracranial hypertension (IIH).MethodsWe created an AT model from 2862 VFs prospectively collected from 330 eyes in the IIH Treatment Trial (IIHTT). We compared baseline IIH AT patterns with their descriptive VF classifications from the IIHTT.ResultsThe optimum IIH AT model yielded 14 ATs resembling VF patterns reported in the IIHTT. Baseline VFs contained four or fewer meaningful ATs in 147 (89%) of study eyes. AT2 (mild general VF depression pattern) demonstrated the greatest number of study eyes with meaningful AT weight at baseline (n = 114), followed by AT1 (n = 91). Other ATs captured patterns of blind spot enlargement, hemianopia, arcuate, nasal defects, and more nonspecific patterns of general VF depression. Of all ATs, AT1 (normal pattern) had the strongest correlation with mean deviation (r = 0.69, P < 0.001). For 65 of the 93 VFs with a dominant AT, this AT matched the expert classification.ConclusionsArchetypal analysis identifies quantifiable, archetypal VF defects that resemble those commonly seen in IIH.Translational RelevanceArchetypal analysis provides a quantitative, objective method of measuring and monitoring disease-specific regional VF defects in IIH.

Predicting the development of normal tension glaucoma and related risk factors in normal tension glaucoma suspects

This study investigated the predicted risk factors for the development of normal-tension glaucoma (NTG) in NTG suspects. A total of 684 eyes of 379 NTG suspects who were followed-up for at least 5 years were included in the study. NTG suspects were those having (1) intraocular pressure within normal range, (2) suspicious optic disc (neuroretinal rim thinning) or enlarged cup-to-disc ratio (≥ 0.6), but without definite localized retinal nerve fiber layer (RNFL) defects on red-free disc/fundus photographs, and (3) normal visual field (VF). Demographic, systemic, and ocular characteristics were determined at the time of the first visit via detailed history-taking and examination of past medical records. Various ocular parameters were assess using spectral-domain optical coherence tomography and Heidelberg retinal tomography. Conversion to NTG was defined either by the presence of a new localized RNFL defect at the superotemporal or inferotemporal region on disc/fundus red-free photographs, or presence of a glaucomatous VF defect on pattern standard deviation plots on two consecutive tests. Hazard ratios were calculated with the Cox proportional hazard model. In total, 86 (12.6%) of the 684 NTG suspects converted to NTG during the follow-up period of 69.39 ± 7.77 months. Significant (P < 0.05, Cox regression) risk factors included medication for systemic hypertension, longer axial length, worse baseline VF parameters, thinner baseline peripapillary RNFL, greater disc torsion, and lamina cribrosa (LC) thickness < 180.5 μm (using a cut-off value obtained by regression analysis). Significant (P < 0.05, Cox regression) risk factors in the non-myopic NTG suspects included medication for systemic hypertension and a LC thinner than the cut-off value. Significant (P < 0.05, Cox regression) risk factors in the myopic NTG suspects included greater disc torsion. The results indicated that 12.6% of NTG suspects converted to NTG during the 5–6-year follow-up period. NTG suspects taking medication for systemic hypertension, disc torsion of the optic disc in the inferotemporal direction, and thinner LC of the optic nerve head at baseline were at greater risk of NTG conversion. Related baseline risk factors were different between myopic and non-myopic NTG suspects.

Multicolor Imaging for Detection of Retinal Nerve Fiber Layer Defect in Myopic Eyes With Glaucoma

To investigate the diagnostic performance of multicolor imaging for detection of retinal nerve fiber layer (RNFL) defects in myopic eyes with glaucoma. Comparative diagnostic analysis. A total of 150 myopic eyes of 138 patients (< -1.00 diopter or axial length >24 mm) underwent multicolor imaging by Spectralis (Heidelberg Engineering GmbH) optical coherence tomography (OCT). Two independent observers graded the RNFL visibility score and determined the location of the RNFL defect on each image. Readings were taken from the superior and inferior areas. The diagnostic performances of multicolor, green-reflectance, and blue-reflectance images for detection of the RNFL defect were compared with those of conventional fundus and red-free RNFL photographs. The interobserver agreement on the RNFL visibility score was substantial for fundus and RNFL photographs and multicolor and green-reflectance images and was perfect for blue-reflectance images. The interobserver agreement on the location of the RNFL defect was better when using multicolor imaging than when using conventional photography. The green-reflectance image (2.89 ± 0.31) showed the highest RNFL visibility score, followed by blue-reflectance (2.88 ± 0.32) and multicolor (2.57 ± 0.63) images. The sensitivity of multicolor imaging (94.9%, 93.2%, and 91.5% for green-reflectance, blue-reflectance, and multicolor images, respectively) was significantly higher than that of fundus photography (83.1%) for detection of superotemporal RNFL defects (all P < .05). It was significantly higher for inferotemporal defects than those of fundus and RNFL photographs (all P < .05). Multicolor imaging can visualize the glaucomatous RNFL defects in myopic eyes that are indistinguishable on conventional photography.

Agreement between Compass Fundus Perimeter New Grid and 10-2 Testing Protocols for Detecting Central Visual Field Defects

To evaluate the agreement between Compass New Grid (NG) and 10-2 test protocols for detecting early glaucomatous defects in the central 10 degrees of the visual field (CVFD). Cross-sectional study. A total of 123 eyes of 14 healthy individuals, 17 glaucoma suspects, and 32 glaucoma patients were enrolled. Subjects performed NG and 10-2 Compass automated perimetry testing within 1 week. For both test protocols, total deviation (TD) and pattern deviation (PD) plot CVFDs were defined by 3 contiguous points with probabilities of <5%, <2%, <2% or <5%, <1%, <1%. Cohen's Kappa statistic was used to assess agreement between NG and 10-2 for identifying CVFDs. The Spectralis GMPE Hood Glaucoma Report (investigational software version) macula deviation analysis obtained within 1 year was used for calculating sensitivities and specificities of test protocols. Protocols' agreement, sensitivity, and specificity. Fair to moderate agreement was observed between NG and 10-2 protocols for detecting presence of superior CVFDs on TD (k= 0.57) and PD (k= 0.26) plots and for detecting inferior CVFDs on TD (0.49) and PD (0.27) plots. With the use of OCT macula deviation maps, specificity for detecting CVFD was consistently higher with NG than 10-2 tests for TD plots of the superior hemifield (0.82 and 0.65), inferior hemifield (0.92 and 0.84), and PD plots of the superior hemifield (0.81 and 0.36) and inferior hemifield (0.86 and 0.52). Sensitivity of NG was consistently lower than TD plots of the superior hemifield (0.48 and 0.72), inferior hemifield (0.28 and 0.46), and PD plots of the superior hemifield (0.48 and 0.78) and inferior hemifield (0.20 and 0.52). By using pattern standard deviation (PSD) criterion, the mean PSD values for 10-2 and NG VF tests were 1.61 (95% confidence interval [CI], 1.26-1.96) and 1.81 (95% CI, 1.45-2.17) (P < 0.001), respectively. Although the Compass NG detected fewer CVFDs than the 10-2 test protocol, it did detect CVFDs that were not observed in the Compass 24-2 test in patients with early glaucoma. Therefore, NG may be particularly useful in clinical situations when higher specificity is desired or PSD criterion is used.

EFFICACY AND SAFETY OF COMBINED PHACO TRABECULOTOMY FOR CHRONIC NARROW-ANGLE GLAUCOMA

Introduction:• Primary angle-closure glaucoma was determined as the presence of glaucomatous optic neuropathy caused by high IOP related to a synechial closed-angle on gonioscopy and glaucomatous defects in visual fields and absence of any cause of secondary angle closure.• Outflow reconstructive surgery is a relatively safe procedure because of the absence of a filtering bleb. Trabeculotomy decreases outflow resistance by cleavage of the trabecular meshwork and the inner layers of Schlemm’s canal, which are the regions primarily responsible for the resistance to aqueous outflow.• Some sections of the anterior chamber angle are permanently closed by peripheral anterior synechiae in eyes with chronic angle-closure glaucoma. IOP after removal of the pupillary block depends on the degree of damage to the trabecular meshwork. We combined phacoemulsification and trabeculotomy to try to obtain the lowest possible IOP after a single surgical procedure. Patients:• Retrospective clinical study that included 20 eyes of patients who underwent phacoemulsification surgery and IOL implantation combined with trabeculotomy under deep sclerectomy .• All these patients were found to have PACG together with significant cataract.• These eyes were found to have extensive peripheral anterior synechiae of more than 180° on gonioscopy.