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Purpose: To compare the retinal vascularity, peripapillary vascularity, nerve fiber layer thickness and ganglion cell layer thickness between active, inactive thyroid eye disease (TED) and healthy eyes., Methods: Retrospective comparative cross-sectional cohort study. Patients with TED, active and inactive on the VISA score, and healthy eyes were included. All patients underwent optical coherence tomography angiography with detailed demographic and clinical data capture. Using automated software, retinal and peripapillary vascularity index, nerve fiber layer thickness, and ganglion cell layer thickness were calculated and were compared between the groups., Results: Twenty-four eyes with active TED, 102 eyes with inactive TED and 52 healthy eyes were included. Independent sample t test was used to compare parametric data and Mann-Whitney test to compare non-parametric data. The age and gender were comparable across groups. The peripapillary vascularity index (26.82 ± 4.13 versus 34.92 ± 5.08, p = .002) and the macular vascularity index (20.32 ± 2.5 versus 31.21 ± 3.89, p < .0001) were reduced in active TED eyes versus inactive eyes. Macular vascularity index was comparable in the inactive versus the healthy eyes. The RNFL thickness was increased in the active TED eyes versus the inactive eyes (45.11 ± 18.3 versus 35.55 ± 7, p = .03) and active versus healthy eyes (45.11 ± 18.3 versus 36.28 ± 7.89, p = .03). Ganglion cell layer thickness between all three groups was comparable., Conclusion: Decrease in peripapillary and macular vascular density and increase in RNFL thickness are seen in active TED compared to inactive TED and healthy eyes. In disease inactivity, these parameters are comparable to healthy eyes.

Purpose: To report the differences in choroidal vascularity index (CVI) in thyroid eye disease (TED) and normals and its discriminatory value for differentiating various stages of TED., Methods: Prospective, cross-sectional, non-interventional imaging study. Ninety-four eyes of 54 patients were included and divided into 5 groups - normal controls (C), inactive TED (I), active TED (A), non-inflammatory active TED (NIA) and systemic hyperthyroid disorder but no TED (SYS). Choroidal images were acquired using the swept-source optical coherence tomography and the choroid was binarized to calculate the CVI., Results: Ninety-four eyes were included. Mean age was 44.52 ± 10.02 years (median 46 years, range 19-65 years). Mean IOP was 16.1 ± 3.37 mm Hg (median 16 mm Hg, range 16-24 mm Hg). Mean Spherical equivalent (SE) was -0.08 ± 1.86 diopters (median 0, range -2.5 to +2.25). Intra-rater agreement was 0.84 ( p < 0.001). Inter-rater agreement was noted to be 0.85 ( p < 0.001) for consistency and 0.77 ( p < 0.001) for absolute agreement. CVI in the A group was 70.11 ± 3.38% and in the NIA group was 69.32 ± 3.5%. Both were comparable to each other and significantly higher than the C, I and SYS groups ( p < 0.001). Multiple regression showed that the Clinical Activity Score (CAS) had a positive effect and spheroequivalent had a negative effect on the CVI. At CVI of 66.83%, active TED can be diagnosed with sensitivity of 91.67% and specificity of 82.14%                 ., Conclusions: CVI is significantly higher in active TED and NIA TED compared to other groups. It has a good value in differentiating the non-inflammatory active TED eyes from the inactive eyes.

Progressive optic neuropathies such as glaucoma are major causes of blindness globally. Multiple sources of subjectivity and analytical challenges are often encountered by clinicians in the process of early diagnosis and clinical management of these diseases. In glaucoma, the structural damage is often characterized by neuroretinal rim (NRR) thinning of the optic nerve head, and other clinical parameters. Baseline structural heterogeneity in the eyes can play a key role in the progression of optic neuropathies, and present challenges to clinical decision-making. We generated a dataset of Optical Coherence Tomography (OCT) based high-resolution circular measurements on NRR phenotypes, along with other clinical covariates, of 3973 healthy eyes as part of an established clinical cohort of Asian Indian participants. We introduced CIFU, a new computational pipeline for CIrcular FUnctional data modeling and analysis. We demonstrated CIFU by unsupervised circular functional clustering of the OCT NRR data, followed by meta-clustering to characterize the clusters using clinical covariates, and presented a circular visualization of the results. Upon stratification by age, we identified a healthy NRR phenotype cluster in the age group 40-49 years with predictive potential for glaucoma. Our dataset also addresses the disparity of representation of this particular population in normative OCT databases., (© 2021. The Author(s).)

Purpose: To study the effects of age, sex, intraocular pressure (IOP), corneal thickness, axial length (AXL), disc area, and the signal strength of the scan on optical coherence tomography (OCT) parameters of normal subjects in the L V Prasad Eye Institute-Glaucoma Epidemiological and Molecular Genetic Study (LVPEI-GLEAMS), a population-based study., Design: Cross-sectional study., Methods: A total of 1,100 eyes (1,100 subjects) of normal adults aged between 40 and 80 years from LVPEI-GLEAMS underwent macular and optic nerve head imaging with spectral-domain OCT (SDOCT). Effect of age, sex, IOP, central corneal thickness (CCT) and AXL, disc area, and signal strength of the OCT scan on retinal nerve fiber layer (RNFL) thickness, rim area, and ganglion cell-inner plexiform layer (GC-IPL) thickness measurements were evaluated using univariate and multivariate regression models., Results: Mean rim area, RNFL, and GC-IPL thickness were 1.31 mm 2 (standard deviation [SD] = 0.22), 93.7 μm (SD = 9.3) and 79.6 μm (SD = 8.7), respectively. Age had a negative association with RNFL thickness (coefficient: -0.18, P < .001) and GC-IPL thickness (-0.18, P < .001). GC-IPL thickness was significantly less in women than in men (-1.05, P < .001). AXL had a negative association with rim area (-0.05, P < .001). Disc area was positively associated with RNFL thickness (4.90, P < .001) and rim area (0.15, P < .001). Signal strength of OCT scan was positively associated with RNFL thickness (1.6, P < .001) and negatively associated with rim area (-0.02, P < .001)., Conclusion: Age, sex, AXL, disc area, and signal strength of the scan were significantly associated with OCT measurements. These factors may need to be considered while interpreting the OCT parameters in pathologic conditions such as glaucoma., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: The present study's objectives are 1) to describe a novel model of Diabetic Retinopathy Capacity Building (DRCB) for optometrists in the detection of diabetes-related retinal pathology in India and 2) to assess the outcomes of this model by comparing the ability of optometrists to detect these diseases using retinal photographs, vis-à-vis, a specialist ophthalmologist., Methods: The DRCB model for optometrists conducted between August 2016 and August 2018 included training, certification in the screening, and referral guidelines for Diabetic Retinopathy (DR) and hospital-and community-based service delivery. Training included a 7-month long fellowship in DR and mentored participation as cofacilitators in 1-day orientation workshops on DR screening guidelines across India. The sensitivity and specificity of study optometrists in screening for DR by fundus photography were compared to a retina specialist before certification., Results: A total of eight optometrists successfully completed their DR fellowship in the project duration of 24 months. The sensitivity and specificity of detection of any DR were 95 and 79%, any Diabetic macular edema (DME) was 80 and 86%. The sensitivity and specificity of detection of sight threatening DR were 88 and 90% and DME was 72% and 92% respectively. Seven workshops were cofacilitated by study optometrists training 870 optometrists in DR screening guidelines across India., Conclusion: The present DRCB model results advocate for an optometry coordinated DR screening in India. Lessons learnt from this model can be useful in designing community-based task sharing initiatives for optometrists in DR screening., Competing Interests: None

Objectives: To assess the ability of teleophthalmoscopic grading of peripheral anterior chamber depth (PACD) using the van Herick (vH) technique in detecting gonioscopically occludable angle; and to determine whether combining results from vH grading and ocular biometry can improve the accuracy to diagnose gonioscopically occludable angle METHODS: This cross-sectional study was an offshoot of a rural population-based study, Glaucoma Epidemiology and Molecular Genetic Study (GLEAMS). A masked urban ophthalmologist graded digital slit lamp photographs of PACD by vH technique. Sussman four-mirror lens was used to perform dark room indentation gonioscopy. Cutoff values of the tests were, vH technique: grade ≤ 2, central anterior chamber depth (ACD), as well as axial length: ≤ 25th percentile and lens thickness ≥ 75th percentile value of the study population., Results: We studied 1965 eyes of 1029 adult participants. The vH grade was ≤2 in 188 (9.5%) eyes. The angle was occludable by gonioscopy in 101 (5.1%) eyes. The performance of the vH test to rule out gonioscopically occludable angle was good [negative predictive value (NPV): 97.3%], despite low sensitivity (52.5%), while its efficacy to rule in the condition was low [positive predictive value (PPV): 28.2%] despite high specificity (92.8%). However, test combination strategy increased the PPV nearly twofold (53.8%). The calculated PPV at 10% prevalence of gonioscopically occludable angle was even higher (70.5%)., Conclusions: Van Herick technique can be incorporated into a teleophthalmology program by means of slit lamp photographs of PACD. Combined vH grading and ocular biometry improved the predictability of a gonioscopically occludable angle.

Purpose: To report the clinical features, treatment outcomes and blindness associated with steroid-induced glaucoma in vernal keratoconjunctivitis (VKC)., Materials and Methods: Records of patients with VKC, who visited our tertiary centre from 1992 and 2009, were reviewed and those with steroid-induced glaucoma were included in the study. Glaucoma was diagnosed based on intraocular pressure (IOP) ≥22 mm Hg on two consecutive visits (ocular hypertension) and/or glaucomatous optic disc damage. Blindness was defined as best corrected visual acuity of ≤20/400 or visual field <10°., Results: Of the 4062 VKC subjects, 91 (157 eyes) had steroid-induced glaucoma (SIG), showing a prevalence of 2.24%. Of these 87% were men. The median (IQR) age at onset of VKC was 12 years (7-17). At presentation, the median duration of VKC was 48 months (24-72) and the median duration of steroid usage was 24 months (12-36). The median cup-to-disc ratio (CDR) was 0.9 (0.7-0.9) and median mean deviation was -21.9 dB (-30.0 to -10.2). IOP was medically controlled in 66% eyes (104/157) and 34% eyes (53/157) needed glaucoma surgery. High presenting IOP (OR: 1.04; p=0.05) and increased duration of steroid usage (OR: 1.07; p=0.02) were significantly associated with need for glaucoma surgery. At presentation, 29/91 subjects (31.8%) were bilaterally blind due to SIG. Higher CDR at presentation was significantly associated with blindness in this cohort (p=0.02)., Conclusion: In this cohort of VKC with SIG, the disease predominantly affected adolescent males. Glaucoma was severe with one-third needing surgery and one-third blind due to SIG., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To report the prevalence of primary glaucoma as identified by study optometrists of the L. V. Prasad Eye Institute - Glaucoma Epidemiology and Molecular Genetics Study (LVPEI-GLEAMS)., Methods: Two study optometrists and a total number of 3833 individuals participated in the LVPEI-GLEAMS. All subjects underwent a complete medical history and comprehensive eye examination including slit lamp photography, imaging of anterior and posterior segment, frequency doubling technology and standard automated perimetry including gonioscopy with a Sussman 4 mirror goniolens, post dilated evaluation of the optic disc and fundus was done with a 90 D lens by the study optometrist. A diagnosis of primary open angle glaucoma (POAG), primary angle closure suspect (PACS), primary angle closure (PAC), primary angle closure glaucoma (PACG), normal tension glaucoma (NTG), glaucoma/disc suspect or no glaucoma was made based on the clinical examination., Results: Estimated prevalence of OAG (POAG and NTG) was 1.07% (0.74-1.39), PACS 2.03% (1.58-2.48), PAC 1.77% (1.35-2.19), PACG 0.21% (0.06-0.35) as identified by the study optometrists on site., Conclusions: Prevalence of all the categories of primary glaucoma, as reported by the study optometrists of LVPEI-GLEAMS was comparable to previous findings of other regions in South India.

Aims: To determine the profile of CSCR patients from a tertiary health care set-up in India., Methods and Material: A total of 2780 (2447 males and 333 females) patients with a diagnosis of CSCR were included. Data regarding the demographics, profile of CSCR and systemic diseases, if any, were collected from a tertiary eye care network in South India from January 2012 to December 2016., Results: The prevalence of CSCR was found to be 1.7% (A total 2780 patients, with mean age of 42.3±10.1 years). A total of 2031 patients had a unilateral and 749 had bilateral involvement. Acute and chronic CSCR was seen in 1932 (69.5%) and 848 (30.5%) eyes respectively. The mean uncorrected visual acuity of the patients was 0.51±0.45 log MAR (Snellen equivalent 20/60) while the mean best corrected visual acuity was 0.32±0.40 log MAR (Snellen equivalent 20/40). History of smoking and steroid use was present in 214 (7.7%) and 758 (27.3%) individuals respectively. Hypertension and diabetes mellitus was present in 106 (3.8%) and 51 (1.8%) patients respectively. Most of patients {824 (29.6%) patients} were shift-workers. Laser was done in 336 (12.1%) acute and 223 (8%) chronic CSCR patients. Photodynamic therapy was used in 12 acute and 12 chronic cases., Conclusion: Prevalence of CSCR was 1.7%. The study provides an overview of patient profile among Indian subjects., (© NEPjOPH.)

Purpose: To compare the choroidal thickness (CT) of subjects with Retinitis Pigmentosa (RP) with age-matched healthy subjects and to correlate the visual acuity with retinal parameters including central macular thickness (CMT), inner segment/outer segment junction (IS/OS junction) integrity, external limiting membrane (ELM) integrity and choroidal thickness in subjects with RP., Methods: Eighty-eight eyes (69 patients) with typical RP and 188 eyes of 104 healthy subjects were enrolled between September 2012 and January 2013. All subjects underwent a comprehensive ocular examination including choroidal imaging using enhanced depth imaging with spectral domain optical coherence tomography. Outcome measures were CT difference between RP and age-matched healthy subjects; and correlation of various factors such CMT, IS/OS junction integrity, ELM integrity, and CT with visual acuity., Results: Among RP subjects, mean age was 31.39 ± 13.4 years with a mean BCVA of 0.99 ± 0.94 logMAR. Mean spherical equivalent was -0.6 ± 1.6D. Mean CMT was 148.48 ± 119 μm. Mean subfoveal CT was 296.9 ± 72 μm. Mean IS/OS and ELM integrity was 42.2 ± 46.6% and 43.75 ± 45.7%, respectively. The mean age was 40.0 ± 13.5 years with a mean spherical equivalent of 0.18 ± 0.6D for the normal age-matched healthy group. Mean subfoveal CT was 283.1 ± 47.8 μm. CT at various locations in patients of various ages in the RP group did not show any statistical significant difference (P = ≫0.05) in comparison with age-matched healthy subjects. On multivariate regression, ELM percentage integrity had the strongest association with best corrected visual acuity, followed by IS/OS junction percentage integrity. Subfoveal choroidal thickness had very weak correlation with visual acuity as well other retinal parameters. There was a significant difference in the outer retinal structure integrity (p = 0.002) and CMT (p = 0.02) between the eyes with good (⩾20/200) and poor vision (<20/200), but not in subfoveal choroidal thickness (p = 0.3)., Conclusions: Our study results did not show any significant difference in choroidal thickness between subjects with RP and age-matched healthy subjects. Choroidal thickness correlated better with the age but not with the vision or outer retinal structures in eyes with RP. Outer retinal structure integrity and CMT had a better correlation with visual acuity.

Purpose: To evaluate choroidal thickness (CT) change in various grades of diabetic retinopathy (DR) in comparison to age-matched healthy subjects., Methods: This prospective observational study included 227 eyes of 125 subjects with diabetes (study group: 58 females) and 197 eyes of 110 age-matched healthy subjects (control group: 66 females). Collected data included age, gender, duration of diabetes, glycemic control, comprehensive ocular examination, fundus photography, and CT measurement on spectral domain ocular coherence tomography using enhanced depth imaging., Results: Mean age in the study group was 57.0 ± 9.37 years (43-73 years). The mean age was 41.48 ± 5.43 years in the control group. Subjects with diabetes with (252.8 ± 55.6 microns) and without (261.71 ± 51.8 microns) retinopathy had significantly thinner choroids when compared to the control group (281.7 ± 47.7 microns; P = 0.032). Seventy-four of 227 eyes did not have any evidence of DR, 89 eyes had features of nonproliferative diabetic retinopathy (NPDR), and 33 eyes had treatment naïve proliferative diabetic retinopathy (PDR). Thirty-one PDR eyes had received previous laser photocoagulation. Subjects with diabetes without retinopathy had a greater subfoveal choroidal thickness (SFCT) than subjects with diabetes with retinopathy (P < 0.001). Eyes with PDR (243.9 ± 56.2 microns) had thinner SFCT than those with NPDR (238.98 ± 111.23 microns). There was no difference in the SFCT between treated (laser photocoagulation done; 251.784 ± 103.72 microns) and treatment naïve PDR (258.405 ± 89.47 microns, P = 0.23)., Conclusions: Control eyes had greater SFCT compared to subjects with diabetes, with and without retinopathy. The thinning progressed with increasing severity of DR. Choroidal thinning may contribute to DR pathogenesis.

Purpose: To assess the choroidal thickness changes in eyes with macular telangiectasia Type 2 and their relationship with the integrity of outer retinal structures and visual acuity., Methods: This is a prospective observational study that included 81 eyes (41 subjects) with macular telangiectasia Type 2, including 21 women who underwent enhanced depth choroidal imaging. The choroidal thickness measurements were made at the fovea and at 5 points with an interval of 500 μm in both directions, nasal and temporal from the fovea, and were compared with age-matched healthy subjects. Masked observers assessed the outer retinal structure integrity. Stepwise regression was used to find the relationship between age, spherical equivalent, central macular thickness, integrity of the inner segment/outer segment junction, external limiting membrane integrity, and subfoveal choroidal thickness (SFCT)., Results: The mean age of the subjects was 55.2 ± 7.8 years in study subjects. The mean SFCT was 274.6 ± 45.7 μm. There was no significant difference between the SFCT in eyes with macular telangiectasia Type 2 and age-matched healthy subjects (P = 0.38). There was no correlation between the visual acuity (r = 0.008); integrity of inner segment/outer segment (r = 0.54); external limiting membrane (r = 0.47); central macular thickness (r = 0.31) and SFCT., Conclusion: Choroidal thickness did not vary between eyes with macular telangiectasia Type 2 and age-matched healthy subjects. There was no correlation between SFCT and visual acuity, and integrity of the outer retinal structures and central macular thickness.

Purpose: To report the clinical features, management, and treatment outcomes of glaucoma in microspherophakia., Methods: Medical records of 159 eyes of 80 subjects with microspherophakia were reviewed. The clinical features at presentation, presence of glaucoma, methods of treatment, and their outcomes were noted. Glaucoma was diagnosed based on intraocular pressure (IOP)≥22 mm Hg on 2 different occasions and/or glaucomatous optic disc damage. Angle closure was defined as occludable angles >270 degrees with or without presence of peripheral anterior synechiae., Results: Glaucoma was diagnosed in 81 eyes (51%). The mean age of subjects was 20±13 years, mean refractive error was -13.5±5.5, the mean IOP was 27.7±11.1 mm Hg. IOP≥22 mm Hg was present in 84% of eyes, disc damage in 59% of the eyes, 75% eyes had angle closure, and 25% had open angle on gonioscopy. Subluxation of crystalline lens was seen in 53 eyes and 14 eyes had dislocation of the lens; systemic associations were present in 21 subjects (3 Marfan syndrome, 18 Weill-Marchesani syndrome). Nine eyes out of 51 and 2 out of 16 eyes responded to medical treatment and laser iridotomy, respectively. Of the 48 eyes that required surgical intervention, 24 eyes underwent trabeculectomy. Complete success probability of trabeculectomy was 86% [95% confidence interval (CI), 63%-95%] at 6 months, 77% (95% CI, 53%-90%) at 1 year, which was maintained till 7 years, and reduced to 61% (95% CI, 26%-84%) at 8 years. Nearly 20% of eyes at presentation and 30% of the eyes at last follow-up were blind due to glaucoma., Conclusions: More than half of the eyes with microspherophakia in this series presented with glaucoma; angle closure was the predominant form of glaucoma. Blindness due to glaucoma in microspherophakia was 20% to 30%.

Background: With the advent of spectral domain optical coherence tomography (SDOCT), there has been a renewed interest in macular region for detection of glaucoma. However, most macular SDOCT parameters currently are thickness parameters which evaluate thinning of the macular layers but do not quantify the extent of area over which the thinning has occurred. We therefore calculated a new macular parameter, "ganglion cell complex surface abnormality ratio (GCC SAR)" that represented the surface area over which the macular thickness was decreased., Purpose: To evaluate the ability of SAR in detecting perimetric and preperimetric glaucoma., Design: Retrospective image analysis., Materials and Methods: 68 eyes with perimetric glaucoma, 62 eyes with preperimetric glaucoma and 165 control eyes underwent GCC imaging with SDOCT. SAR was calculated as the ratio of the abnormal to total area on the GCC significance map., Statistical Analysis: Diagnostic ability of SAR in glaucoma was compared against that of the standard parameters generated by the SDOCT software using area under receiver operating characteristic curves (AUC) and sensitivities at fixed specificities., Results: AUC of SAR (0.91) was statistically significantly better than that of GCC average thickness (0.86, P = 0.001) and GCC global loss volume (GLV; 0.88, P = 0.01) in differentiating perimetric glaucoma from control eyes. In differentiating preperimetric glaucoma from control eyes, AUC of SAR (0.72) was comparable to that of GCC average thickness (0.70, P > 0.05) and GLV (0.72, P > 0.05). Sensitivities at specificities of 80% and 95% of SAR were comparable (P > 0.05 for all comparisons) to that of GCC average thickness and GLV in diagnosing perimetric and preperimetric glaucoma., Conclusion: GCC SAR had a better ability to diagnose perimetric glaucoma compared to the SDOCT software provided global GCC parameters. However, in diagnosing preperimetric glaucoma, the ability of SAR was similar to that of software provided global GCC parameters.

Purpose: To evaluate the relationship between intraocular pressure (IOP) and the rate of visual field (VF) progression in treated glaucoma., Methods: In a clinic-based, retrospective study, data of consecutive primary open-angle and angle-closure glaucoma patients with ≥ 5 VFs between 1989 and 2008 were analyzed. The Guided Progression Analysis software, which provides the rate of change of Visual Field Index per year, was used to assess the rate of progression (ROP). IOP measurements during the VF examination visits were extracted, and mean, peak, and fluctuation (SD) of IOP during the follow-up were calculated. Relationships between IOP parameters and ROP were analyzed using regression models. Other risk factors evaluated were age, sex, type of glaucoma, presence of hypertension and diabetes, severity of VF loss at presentation, glaucoma surgery during follow-up, number of antiglaucoma medications, and follow-up duration., Results: During the study period, 296 eyes of 213 glaucoma patients had undergone ≥ 5 VFs. IOP fluctuation was the only IOP parameter significantly associated with ROP (β=-0.37, P=0.02). Evaluated in a multivariate model with other risk factors, the severity of VF damage at presentation (β=0.08, P=0.002) and IOP fluctuation (β=-0.35, P=0.02) remained significantly associated with ROP. Greater IOP fluctuation was seen in eyes undergoing glaucoma surgery and eyes requiring more antiglaucoma medications during follow-up., Conclusions: Long-term IOP fluctuation was the most important IOP parameter associated with increased ROP of glaucomatous VF loss. This association is likely due to the confounding effect of enhanced therapy in eyes suspected to be progressing.

Purpose: In the developing world, more than 90% of glaucoma is undetected due to the lack of appropriate screening methods. The LV Prasad Eye Institute Glaucoma Epidemiology and Molecular Genetic Study (LVPEI-GLEAMS) is a population-based study which aims to estimate the prevalence of, along with clinical, systemic and genetic risk factors for glaucoma in a rural population sampled from the state of Andhra Pradesh, India. The study aims to develop community screening strategies to diagnose glaucoma. This article describes the methodology adopted in LVPEI-GLEAMS., Methods: A sample of 3833 participants aged 40 years and older has been estimated to be enrolled using a compact segment sampling method with probability proportionate to size. Each participant will undergo a complete medical history and comprehensive eye examination including slit lamp photography, imaging of anterior and posterior segment, frequency doubling technology and standard automated perimetry. Additionally, glycosylated hemoglobin will be measured and a genetic profile based on candidate gene analysis will be undertaken. Clinical, biochemical and genetic data will be stored in a computerized database and analyzed. The novelty of this study lies in the fact that it is conducted at a vision center (primary eye care center serving a population of 50,000) by a vision technician (high school educated rural youth trained in basic ophthalmic techniques for a year)., Conclusion: Information from the diagnostic techniques of the study will be used to develop effective community-level screening strategies, and insights from risk factors associated with glaucoma will help develop appropriate detection and management strategies.

Purpose: : To determine the effect of cataract on the Visual Field Index (VFI) in glaucoma patients., Methods: : Reliable visual fields (VFs) of 53 patients (53 eyes) with primary glaucoma who underwent phacoemulsification either alone or combined with trabeculectomy were analyzed before and after surgery. All patients had VFs within a period of 15 months before and after surgery. VFI, mean deviation (MD), and pattern standard deviation (PSD) before surgery were compared with those after surgery., Results: : Median (25th and 75th percentiles) MD after cataract surgery [-10.52 dB (range, -19.25 to -4.86 dB)] was significantly better (P=0.003) than that before surgery [-11.74 dB (range, -20.61 to -7.15 dB)]. Median PSD after surgery [4.76 dB (range, 2.48 to 9.83)] was worse (P=0.01) than that before surgery [3.50 dB (range, 1.93 to 8.20 dB)] when eyes with MD better than -20 dB were considered (41 eyes). VFI after surgery [80% (range, 44% to 94%)] was similar (P=0.92) to that before surgery [77% (range, 37% to 92%)]. MD improved while VFI remained unchanged in both nuclear sclerotic (n=41) and posterior subcapsular cataracts (n=12)., Conclusions: : MD and PSD were significantly affected, whereas VFI was not affected by cataract. VFI may be a more robust measure of VF damage than MD or PSD in glaucomatous eyes with coexisting cataracts.

Purpose: To evaluate the influence of optic disc size and disease severity on the diagnostic validity of optical coherence tomography (Stratus OCT), scanning laser polarimetry [GDx variable corneal compensator (VCC)], and confocal scanning laser ophthalmoscopy [Heidelberg retina tomograph II (HRT II)] in Indian eyes with glaucoma., Methods: Ninety-five normal and 125 glaucoma patients underwent imaging with Stratus OCT, GDx VCC, and HRT II. One eye of each person was randomly selected for analysis. Using disc area determined on HRT II, discs were classified as small (<2 mm), moderate (2 to 3 mm), and large (>3 mm). The parameter with the best sensitivity for each device, at a fixed specificity, was compared for different disc sizes. Logistic marginal regression was used to study the effect of disc size and disease severity (mean deviation on standard automated perimetry) on the diagnostic performance of these imaging devices., Results: At a fixed specificity of 84.2%, the sensitivity of HRT II was significantly different for varying disc sizes (P=0.0004). The sensitivities for dissimilar disc sizes were not significantly different for the GDx VCC (P=0.928) or Stratus OCT (P=0.381). Logistic marginal regression also showed that sensitivity of HRT II increased with increasing disc size, whereas sensitivity of OCT and GDx were independent of the disc size. The sensitivity of all 3 technologies increased with increasing disease severity (decreasing mean deviation)., Conclusions: Optic disc size affects the diagnostic capability of HRT II but not that of GDx VCC or Stratus OCT. The sensitivity of all 3 imaging technologies increased with increasing disease severity.