Glaucomatous Field Defects Research Articles

A validated web-application (GFDC) for automatic classification of glaucomatous visual field defects using Hodapp-Parrish-Anderson criteria.

Subjectivity and ambiguity of visual field classification limits the accuracy and reliability of glaucoma diagnosis, prognostication, and management decisions. Standardised rules for classifying glaucomatous visual field defects exist, but these are labour-intensive and therefore impractical for day-to-day clinical work. Here a web-application, Glaucoma Field Defect Classifier (GFDC), for automatic application of Hodapp-Parrish-Anderson, is presented and validated in a cross-sectional study. GFDC exhibits perfect accuracy in classifying mild, moderate, and severe glaucomatous field defects. GFDC may thereby improve the accuracy and fairness of clinical decision-making in glaucoma. The application and its source code are freely hosted online for clinicians and researchers to use with glaucoma patients.

Performance of perimetric glaucoma staging systems and their preference patterns among the Indian eye care practitioners.

Various systems are available to stage glaucomatous field defects into different severity grades. Still, the preference for such systems among Indian eye care practitioners (ECPs) and the consensus between them are not explored. To compare the clinical performance of perimetric glaucoma staging systems and to assess their preference patterns among Indian ECPs. Retro-prospective cross-sectional study. Three investigators stratified 400 perimetry reports using four systems: Hodapp Anderson Parrish (HAP), enhanced Glaucoma Severity Staging (eGSS), Advanced Glaucoma Intervention Study (AGIS), and Collaborative Initial Glaucoma Treatment Study (CIGTS). Their performance was compared in terms of agreement and association. Following this, 30 ECPs from across the country segregated a subset of reports (n = 20) into different stages based on their system of choice, and their preferences/perceptions about the available perimetry staging systems were enquired and documented. Descriptive statistics, Kruskal-Wallis, Cohen's kappa, and Spearman's correlation. For the consolidated severity stages, substantial agreements (K ranging from 0.61 to 0.75) were found between all the systems, except for HAP-CIGTS (K = 0.58) and AGIS-CIGTS (K = 0.51). All ECPs were aware of perimetry staging systems, and a high preference was reported for HAP (97%) due to ease of implementation and interpretation. Among the four staging systems, the highest agreement was found between HAP and eGSS. A majority of ECPs proposed the need for a uniform classification system across the practices for clinical comparisons and patient education.

Detectability of Visual Field Defects in Glaucoma Using Moving Versus Static Stimuli for Perimetry.

We have previously shown that using moving, instead of static, stimuli extends the effective dynamic range of automated perimetry in glaucoma. In this study, we further investigate the effect of using moving stimuli on the detectability of functional loss. We used two experimental perimetry paradigms to test 155 subjects with a diagnosis of glaucoma or glaucoma suspect, and 34 healthy control subjects. One test used stimuli moving parallel to the average nerve fiber bundle orientation at each location; the other used static stimuli. Algorithms were otherwise identical. Sensitivities to moving stimuli were transformed to the equivalent values for static stimuli based on a Bland-Altman plot. The proportions of locations outside age-corrected normative limits were compared, and test-retest variability was compared against defect depth for each stimulus type. More tested locations were below the fifth percentile of the normative range for that location using static stimuli. However, among locations abnormal according to standard clinical perimetry on the same day, 19.2% were abnormal using static stimuli, versus 20.5% using moving stimuli (P = 0.372). Test-retest variability was 44% lower for moving stimuli across the range of defect depths. When compared with static automated perimetry and expressed on a common scale, moving stimuli extend the effective dynamic range and decrease variability, without decreasing the detectability of known functional defects. Moving stimuli provide a method to improve known problems of current clinical perimetry.

Commentary: Rethinking 10-2 visual fields in early diagnosis of glaucoma for a glided glaucoma practice: The right choice to pick up a feeble noise?

Commentary: Rethinking 10-2 visual fields in early diagnosis of glaucoma for a glided glaucoma practice: The right choice to pick up a feeble noise?

Correlation between Interocular Asymmetry of Corneal Hysteresis and Visual Field Defect in Glaucoma.

To evaluate the relationship between interocular asymmetries of corneal hysteresis (CH) and visual field defects in Korean patients with glaucoma. A total of 444 eyes from 222 participants with glaucoma in at least one eye were enrolled. CH was measured using an ocular response analyzer (Reichert Technologies Inc). Eyes of each participant were classified into "better eye" and "worse eye" based on the mean deviation (MD) value of visual field test. The correlation between interocular differences in intraocular pressure, axial length, central corneal thickness, CH, and MD values was evaluated using Spearman correlation analysis. To exclude the possible effect of antiglaucoma medication on corneal properties, additional analyses were performed on eyes without any glaucoma treatment at the time of CH measurement (treatment-naive group). Median (interquartile range) MD value was -3.71 dB (-6.87 to -1.30 dB) in the better eye and -10.20 dB (-16.32 to -5.62 dB) in the worse eye. When the correlation between the asymmetry of the MD value and asymmetry of intraocular pressure, axial length, central corneal thickness, and CH were evaluated, only interocular differences in CH were significantly associated with interocular differences in MD values (rho = 0.214, p = 0.001). Among the 222 participants, 60 (27.0%) were treatment-naive group. In these eyes, interocular differences in CH were also significantly associated with interocular differences in the MD values (rho = 0.285, p = 0.029). The interocular asymmetry of CH was significantly correlated with the interocular asymmetry of visual field defects in glaucoma.

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.

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 & 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.

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.

Vertical Position of the Central Retinal Vessel in the Optic Disc and Its Association With the Site of Visual Field Defects in Glaucoma

The purpose of this study was to investigate the association between the vertical position of the central retinal vessel (CRV) within the optic nerve head (ONH) and the site of visual field defects (VFDs) in glaucoma. Cross-sectional study. The vertical position of the CRV was identified in 134 glaucoma eyes and 61 normal eyes at the point at which CRV exited the lamina cribrosa (LC) onto the ONH surface, by using spectral-domain optical coherence tomography (exit position). The position was also identified at the entry point into the LC from the retrolaminar ONH region (entry position), which was little influenced by glaucomatous LC deformation, therefore close to the original position before the glaucoma development. Positions were compared among glaucoma eyes with different sites of VFDs, and between glaucoma and normal eyes. In glaucoma eyes, the entry position of the CRV was in the superior ONH region in 63.0% of eyes with superior VFDs and in the inferior ONH region in 97.8% of eyes with inferior VFDs (P < .0001). The exit position exhibited a similar percentage. The vertical CRV positions were not significantly different between glaucoma and normal eyes, both at the entry and exit positions. Eyes with CRVs in the superior ONH region were significantly more likely to form VFDs in the superior hemifields and vice versa. The vertical position of the CRV was little altered by the development of glaucoma. The original position of the CRV before the development of glaucoma may influence regional susceptibility to glaucomatous stress and may be useful in predicting initial sites of VFDs.

Comparison of 10-2 and 24-2C Test Grids for Identifying Central Visual Field Defects in Glaucoma and Suspect Patients

To compare the ability of 24-2C and 10-2 test grids in measuring visual field global indices, identifying central visual field defects, and facilitating macular structure-function analysis with OCT scans in glaucoma and glaucoma suspect patients. Prospective, cross-sectional study. One eye from 131 glaucoma and 57 glaucoma suspect patients recruited from a referral-only, university-based glaucoma clinic. Each subject underwent perimetric testing using 24-2C SITA-Faster and 10-2 SITA-Fast in random order, and Cirrus OCT macular imaging (Ganglion Cell Analysis) for structure-function correlations. Visual field global indices (mean deviation, pattern standard deviation, binarized "cluster" pass/fail, and central mean sensitivity), number and proportion of visual field defects, and structure-function concordance with the Cirrus OCT deviation map following visual field location displacement for correspondence with underlying retinal ganglion cell position. Global indices (mean deviation, pattern standard deviation, and central mean sensitivity) were similar between both grids. The 10-2 detected more defects compared with the 24-2C (P < 0.0001 for all patients, P= 0.006 for glaucoma patients). This was preserved when analyzing the proportion of defects in the central visual field for all patients (P= 0.02) but was not significantly different for glaucoma patients (P= 0.051). The 10-2 identified more central "clusters" of 2+ contiguous points of deficit (P < 0.0001). Structure-function comparisons performed at locations where visual field and OCT test locations were colocalized revealed greater concordance of structural and functional deficits using the 10-2 (P < 0.0001). The 10-2 took a median of 201 seconds, and the 24-2C took a median of 154 seconds, corresponding to the different thresholding algorithms. The 24-2C and 10-2 test grids return similar global indices of visual field performance and proportionally similar amounts of central visual field loss. The additional points in the 10-2 grid return more "clusters" of defects and a greater rate of structure-function concordance compared with the 24-2C test grid. Thus, the 24-2C can identify the presence of a clustered central visual field defect using similar probability criteria, whereas the 10-2 may be more useful in comprehensively characterizing the defect and predicting central visual function.

Relationship between peripapillary vessel density and visual function based on Garway-Heath sectorization in open-angle glaucoma.

Purpose:To investigate the relationship between peripapillary vessel density (pVD) and visual field sensitivity (VFS) and between peripapillary retinal nerve fiber layer thickness (pRNFLT) and VFS, based on Garway-Heath sectorization in open-angle glaucoma patients.Methods:Sixty-six eyes of healthy subjects and 84 eyes of glaucoma subjects were included. All subjects underwent several eye examinations, including standard automated perimetry and optical coherence tomography angiography. Sectoral structure-function relationships based on the Garway-Heath sectorization were compared among normal subjects, the ‘mild glaucoma,’ and ‘moderate-to-severe glaucoma’ group. Multivariate analyses were performed for each sector to determine the factors related to VFS. The diagnostic abilities of vessel density parameters and RNFLT were evaluated by calculating the area under the receiver operating characteristic curves (AUROC).Results:The correlation between pVD-VFS and pRNFLT-VFS was statistically significant in the glaucoma group independent of the VFS sector. In the glaucoma group, VFS in the temportal sector was statistically related in a multivariate model to pVD, pRNFLT and age (R2 = 0.721; P = 0.007, < 0.001, .15, respectively). We found pRNFLT and age were significantly associated with VFS in glaucoma. The AUROC values of pVD in the inferotemporal sector of the total, mild, and moderate-to-severe glaucoma (0.843, 0.714, and 0.972, respectively) were comparable to pRNFLT in this sector (0.833, 0.718, 0.948, respectively).Conclusion:Since the relationship between pVD and VFS in the papillomacular area was significant, measuring pVD and RNFLT in the corresponding area will be valuable in expanding our pathophysiologic knowledge of the paracentral field defects in glaucoma.

Evaluation of Intraocular Pressure Changes with Topical Dexamethasone 0.1%, Prednisolone 1% and Difluprednate 0.05% Postcataract Surgery- A Randomised Clinical Trial

Introduction: Topical corticosteroids are most commonly used for the control of postoperative inflammation after cataract surgery. Topical steroids may cause increase in Intraocular Pressure (IOP) which, if left untreated may lead to progressive optic nerve damage and glaucomatous field defects. Aim: To compare the ocular hypertensive response of three commonly used corticosteroids in an effort to generate evidence for managing postcataract surgery inflammation more effectively. Materials and Methods: This randomised clinical trial was carried out for a period of one year from November 2018 to October 2019, among 150 patients undergoing cataract surgery. Patients were divided into three groups. Group A-50 patients received topical dexamethasone 0.1%, Group B-50 patients received topical prednisolone 1% and Group C-50 patients received topical difluprednate 0.05% four times a day for six weeks after cataract surgery. Postoperative IOP was recorded preoperatively, on first postoperative day and at the end of first week, third week and sixth week with non contact tonometer and statistical significance was assessed with the help of repeated measures mixed model Analysis of Variance (ANOVA). Results: The mean age of the patients was 64.4±9.39 years, 48% were males and 52% patients were females. Mean IOP in the three drug groups was not statistically significant at 1st week, 3rd week and at 6th week after cataract surgery. Two patients belonging to difluprednate group at the end of 1st week and one patient at the end of 3rd week after cataract surgery developed significant rise in IOP (&gt;31 mmHg). Conclusion: It can be concluded that all three steroids were equally safe and did not cause any statistically significant rise in IOP over six-week postoperative period. However, higher values were noted in difluprednate group at the end of first and third week after cataract surgery.

What do patients with glaucoma see: a novel iPad app to improve glaucoma patient awareness of visual field loss

PurposeGlaucoma patients with peripheral vision loss have in the past subjectively described their field loss as ‘blurred’ or ‘no vision compromise’. We developed an iPad app for patients to self-characterise...

Inter-Eye Association of Visual Field Defects in Glaucoma and Its Clinical Utility.

PurposeTo investigate intereye associations of visual field (VF) defects.MethodsWe selected 24-2 VF pairs of both eyes from 63,604 patients tested on the same date with mean deviation (MD) ≥ −12 dB. VFs were decomposed into one normal and 15 defect patterns previously identified using archetypal analysis. VF pattern weighting coefficients were correlated between the worse and better eyes, as defined by MD. VF defect patterns (weighting coefficients > 10%) in the better eye were predicted from weighting coefficients of the worse eye by logistic regression models, which were evaluated by area under the receiver operating characteristic curve (AUC).ResultsIntereye correlations of archetypal VF patterns were strongest for the same defect pattern between fellow eyes. The AUCs for predicting the presence of 15 defect patterns in the better eye based on the worse eye ranged from 0.69 (superior nasal step) to 0.92 (near total loss). The AUC for predicting superior paracentral loss was 0.89. Superior paracentral loss in the better eye was positively correlated with coefficients of superior paracentral loss, central scotoma, superior altitudinal defect, nasal hemianopia, and inferior paracentral loss in the worse eye, and negatively correlated with coefficients of the normal VF, superior peripheral defect, concentric peripheral defect, and temporal wedge. The parameters are presented in the descending order of statistical significance.ConclusionsVF patterns of the worse eye are predictive of VF defects in the better eye.Translational RelevanceOur models can potentially assist clinicians to better interpret VF loss under measurement uncertainty.

Reversibility of visual field defects through induction of brain plasticity: vision restoration, recovery and rehabilitation using alternating current stimulation.

For decades visual field defects were considered irreversible because it was thought that in the visual system the regeneration potential of the neuronal tissues is low. Nevertheless, there is always some potential for partial recovery of the visual field defect that can be achieved through induction of neuroplasticity. Neuroplasticity refers to the ability of the brain to change its own functional architecture by modulating synaptic efficacy. It is maintained throughout life and just as neurological rehabilitation can improve motor coordination, visual field defects in glaucoma, diabetic retinopathy or optic neuropathy can be improved by inducing neuroplasticity. In ophthalmology many new treatment paradigms have been tested that can induce neuroplastic changes, including non-invasive alternating current stimulation. Treatment with alternating current stimulation (e.g., 30 minutes, daily for 10 days using transorbital electrodes and ~10 Hz) activates the entire retina and parts of the brain. Electroencephalography and functional magnetic resonance imaging studies revealed local activation of the visual cortex, global reorganization of functional brain networks, and enhanced blood flow, which together activate neurons and their networks. The future of low vision is optimistic because vision loss is indeed, partially reversible.

Eye Movement Perimetry and Frequency Doubling Perimetry: clinical performance and patient preference during glaucoma screening.

To evaluate the screening accuracy of an Eye Movement Perimetry (EMP) in comparison with Frequency Doubling Perimetry (FDP) and to investigate the patient preference and perception towards these visual field screening methods. A total of 104 healthy subjects (mean age (SD) of 48 (14) years) and 73 glaucoma patients (mean age (SD) of 52 (13) years) were recruited. All the participants underwent a comprehensive ophthalmic evaluation including the 24-2 SITA standard protocol on the Humphrey Field Analyzer (HFA). This was followed by the 26-point protocol in EMP and the C-20-1 protocol in FDP. During EMP, all subjects were instructed to fixate a central target and to look at the detected peripheral target, followed by refixation of the central target and Saccadic Reaction Time (SRT) towards each of the "seen" stimuli was calculated. Next, a questionnaire was administered to evaluate the patient preference and perception towards the perimetry techniques. Mean SRTs and Robin scores were used to plot Receiver Operating Characteristics (ROC) curves to determine the screening accuracies. From the questionnaire survey, the frequency distributions of the responses were calculated. Robin score and SRT were significantly increased in glaucoma patients in comparison with the age-matched healthy subjects (p < 0.001). The ROC analysis revealed comparable Area Under the Curve (AUC) values (0.95, p = 0.81) with a specificity of 95.2% for FDP and 96.2% for EMP with a sensitivity of 87.7%. Thirty-seven percent of the older age group (≥ 40years) and 65% of severe glaucoma patients showed preference for EMP over FDP. This study results indicate that the customized protocol in EMP provides efficient and rapid means of screening visual field defects in glaucoma, which compared well with FDP. Elderly healthy participants and patients with moderate and severe glaucomatous defectspreferred EMP as it permitted natural reflexive eye movements thereby resembling a real-life test setting.

Posterior scleral deformations around optic disc are associated with visual field damage in open-angle glaucoma patients with myopia.

PurposeTo identify important variables associated with visual field (VF) defects in open-angle glaucoma (OAG) with myopia.Materials and methodsA total of 105 OAG with myopia were enrolled in this cross-sectional study. The disc tilt ratio, disc torsion degree, disc-foveal angle, and area of peripapillary atrophy (PPA) were measured from red-free fundus photographs. Patients underwent Swept-source optical coherence tomography to measure peripapillary retinal nerve fiber layer (RNFL), subfoveal choroidal, and sufoveal scleral thicknesses. Functional evaluation was performed using 24–2 standard automated perimetry. For statistical analyses, logistic regression, artificial neural networks (ANN), and hierarchical cluster analysis were performed.ResultsLogistic regression demonstrated peripapillary RNFL thickness as a significant variable for the presence of VF defects, otherwise ANN identified PPA area, peripapillary RNFL thickness, disc-foveal angle, and disc torsion degree as significant clinical variables in OAG with myopia. Two clusters were made after a hierarchical cluster analysis. Cluster 2 showed significantly worse VF damage than cluster 1 (MD = -5.20±5.25 dB for cluster 2 and -1.84±3.02 dB for cluster 1, P < .001). Cluster 2 had significantly greater disc tilt ratio, disc-foveal angle, and PPA area compared with cluster 1 (P < .001, 0.005, and < .001, respectively).ConclusionsGenerally peripapillary RNFL thickness is considered as an important variable associated with visual field defects in glaucoma patients. ANN identified parameters associated with posterior scleral deformations around optic disc induced by myopic change including PPA area, disc torsion degree, and disc-foveal angle as significant clinical variables for visual field damage in OAG with myopia.

Transient visual field impairment after cold provocation in glaucoma patients with Flammer syndrome.

Background:It is still debatable whether visual field defects in glaucoma have a reversible component and to what extent a temporary loss can be provoked.Objective:To investigate the response of the visual function to a cold provocation in glaucoma patients, particularly to test whether subjects with Flammer syndrome (FS) behaved differently from subjects without FS.Methods:Ten (10) primary open-angle glaucoma (POAG) patients with FS, 7 POAG patients without FS, and 11 healthy controls were tested with program G2 on the Octopus 101 perimeter before and after putting one hand in cold water (4°C) for 2 min. The mean sensitivity (MS) of each visual field was included in the statistical analysis.Results:In glaucoma patients with FS, the mean MS significantly decreased after cold provocation (delta MS = –0.91 dB, CI = –1.43 to –0.39, p = 0.0014). In contrast, the mean MS in glaucoma patients without FS did not change significantly (delta MS = 0.17 dB, CI = –0.43 to 0.78, p = 0.56). Likewise, the mean MS did not change significantly in the healthy controls (delta MS = 0.23 dB, CI = –0.27 to 0.72, p = 0.36).Conclusions:Cold provocation induced a transient visual field deterioration in the glaucoma patients with FS but not in the glaucoma patients without FS or in the healthy controls. We assume this effect to be the result of a transient reduction of ocular blood flow.

Автоматизированная статическая компьютерная периметрия в диагностике нарушений поля зрения при глаукоме

Автоматизированная статическая компьютерная периметрия в диагностике нарушений поля зрения при глаукоме

Quantification of Glaucomatous Field Defect in Primary Open Angle Glaucoma Patients at the time of Presentation: A Retrospective CrossSectional Study

Quantification of Glaucomatous Field Defect in Primary Open Angle Glaucoma Patients at the time of Presentation: A Retrospective CrossSectional Study