Conjunctival changes in different clinical variants of early pseudoexfoliation.

PURPOSE: To evaluate the conjunctival signs in different forms of pseudoexfoliation (PXF) syndrome to identify signs predicting early forms of the disease. METHODS: This observational study included patients with newly diagnosed PXF screened in the outpatient department of glaucoma services. Slit lamp photographs were captured in low and high magnification after full dilatation, and details like melanotic pigmentation, vascularity and tortuosity of vessels, scarring if any, presence of pterygium and actinic changes along with basal Schirmer's test were analysed. Variables in each subtype of PXF previously described by us, namely radial pigmentary (group A), combined pigmentary and classical (group B) and classical PXF (group C), were analysed and compared to age-matched controls. The differences between manifest (group B + C) and unmanifest or early form (group A) were also compared. RESULTS: A total of 89 eyes from 55 patients (M/F = 38:17, 21 unilateral, 34 bilateral, 48 group A, 10 group B and 31 group C) were compared with 40 controls. The Schirmer's test was statically lower in patients with manifest PXF (10 ± 1.4 mm) and unmanifest PXF (14 ± 0.6 mm), p < 0.001. The most frequent conjunctival finding (n = 88) in this cohort was lightly pigmented melanotic pigmentation present close to limbus without evidence of any feeder vessels or actinic changes and associated with pupillary ruff atrophy in the same quadrant. Analysing different PXF forms, there was conjunctival melanosis in one or all quadrants in all forms of PXF which was more prominent in manifest PXF, present in a mean 2 ± 1.7 quadrants in unmanifest and manifest PXF, p = 0.01. CONCLUSION: Conjunctival melanosis with associated pupillary ruff atrophy in the same quadrant may be the earliest signs of early pseudoexfoliation.

Optic nerve head characteristics in eyes with papillomacular bundle defects in glaucoma.

To evaluate the pattern of retinal nerve fibre layer defects (RNFLD) with regard to involvement of papillomacular bundle (PMB) in glaucoma. This observational study included patients attending glaucoma imaging services at our centre from 2011 to 2012. All images were exported to Image J software for analysis and rescaled to a unified scale for measurement of degree of RNFLD defined by its angular width, pattern of involvement with regard to involvement or sparing of PMB in particular and horizontal and vertical distance of central vessel trunk (CVT) from the disc margin. Association of clinical data with pattern of defects with regard to PMB involvement was analysed. Sixty-two fundus photographs with discernible nerve fibre layer defects on red free images were selected, including 48 normal tension glaucoma, two primary angle closure glaucoma (PACG) and 12 primary open angle glaucoma (POAG) eyes. Discernible PMB involvement was seen in 35 eyes which included 31 defects in inferior quadrant while CVT exit was placed in the quadrant opposite to the quadrant of RNFLD in that eye. The mean vertical distance from the nearest disc margin was greater in eyes without PMB involvement, 0.4 ± 0.02 mm, than eyes with PMB defects, 0.3 ± 0.01 mm, p < 0.001. On multivariate logistic regression, PMB involvement was significantly associated with decreased linear horizontal of the CVT from the disc margin, p = 0.003. Selective involvement of superior and inferior PMB suggests different retinotopic representation within the optic disc. Exit of the CVT towards the disc margin may be a predisposing factor for RNFLD and involvement of the PMB.

Barriers to uptake of referral services from secondary eye care to tertiary eye care and its associated determinants in L V Prasad Eye Institute network in Southern India: A cross-sectional study-Report II.

AIM: To investigate the barriers to the uptake of referral services from secondary care centers (SC) to a higher-level tertiary care center (TC) in Southern India. METHODS: A cross-sectional study was conducted in the Mahabubnagar district of Telangana, India, between February 1, 2018 to January 31, 2019 and all those referred from SC to TC between January 1, 2013 to December 30, 2016 were identified for interview. Based on inclusion criteria, of the 960 participants identified, 681 (70.9%) participated in the study. A validated study questionnaire was administered to all participants. Information collected were the demographic details, details related to their referral and barriers to referral. The participants that presented at TC were considered compliant and who did not, were non-compliant. Reasons for non-compliance was also collected. RESULTS: The mean age those interviewed was 46.1 years (SD: 17.3 years) and 429 (63%) were males and 252 (37%) were females. Overall, 516 (75.8%) were compliant, and 165 (24.2%) were non-compliant. The major factors for non-compliance were economic (16.4%) and attitudinal (44.2%) barriers. Within the attitudinal barrier category, the most prevalent individual attitudinal barriers were 'too busy to go to the eye center for treatment (16.4%)'and 'able to manage routine daily activities with current vision (12.1%)'. The multivariable analysis showed that the non-compliant participants had only visited the SC once prior to the referral (odds ratio: 2.82; 95% CI: 1.43-5.57) (p = 0.003). CONCLUSIONS: Participants with only one SC visit, were less likely to comply with referrals and the major barriers to compliance were economical and attitudinal. It is important to address these specific barriers to provide proper counseling to participants during referrals.

Changing trends in barriers to accessing eye care services in rural South India: results from the longitudinal Andhra Pradesh Eye Disease Study III (APEDS III) cohort.

PURPOSE: To assess the changing trends in barriers towards accessing eye care in a rural population cohort from Southern India. METHODS: This is a population-based longitudinal cohort of participants (the Andhra Pradesh Eye Disease study [APEDS]) from three rural regions of Telangana and Andhra Pradesh who were evaluated at baseline (APEDS I; 1996-2000), along with follow-ups at 10 years (APEDS II; 2009-10) and 15 years (APEDS III; 2012-2016). At follow-up, all participants 30 years and above were administered a structured questionnaire on barriers to uptake of eye care services. RESULTS: Of 3810 participants, 1449 had visual impairment (VI). Among them, 1302 noticed a reduction in vision over last five years and 722 sought treatment, a significant improvement from baseline (P < 0.001). Participants were more likely to seek treatment if they were educated (OR = 1.43, 95%CI: 1.07-1.89), had hypertension (OR = 1.36, 95%CI: 1.04-1.77), had VI from causes other than cataract and refractive error (OR = 2.49, 95%CI: 1.56-3.99) and were residents of Adilabad (OR = 2.21; 95%CI: 1.58-3.08) and Mahbubnagar (OR = 3.55; 95%CI: 2.48-5.08) districts. Those with moderate or worse VI were less likely to seek treatment (moderate VI: OR = 0.56; 95%CI: 0.42-0.75, severe VI: OR = 0.34; 95%CI: 0.19-0.57, blindness: OR = 0.38; 95%CI: 0.2-0.73). The most important barriers to uptake of services were, not perceiving loss of vision as a serious problem (25.9%), accepting it an aging process (21.4%) or due to economic reasons (16.0%). CONCLUSION: Personal and economic elements accounted for considerable amounts of barriers for utilization of eye care services. The uptake of services could be improved by addressing these specific barriers and risk factors for non-compliance.

Prevalence of refractive error among Dongarias and use of Folding Phoropter (FoFo) as a field device enabling implementation research in this indigenous community. Tribal Odisha Eye Disease Study (TOES) Report # 13.

PURPOSE: To evaluate the prevalence of uncorrected refractive error (URE) among Dongarias-a particularly vulnerable tribal group in Rayagada, Odisha, India and evaluate if folding phoropter (FoFo) can help achieve on-site correction of URE. METHODS: This was a cross-sectional study. FoFo was used for people with URE. Spherical equivalent (SE) spectacles based on the FoFo refraction were dispensed when distance visual acuity improved to > 6/12. Others were referred to fixed eye centres. Multivariable logistic regression evaluated the relationship of URE with sociodemographic characters and factors predicting acceptance of FoFo. RESULTS: In the study, 7.5% (95% confidence interval [CI]:7-8) people had URE, and included 4% with severe vision impairment and 36% with moderate visual impairment. URE was less common in children. Simple hyperopia was more common in females (25.3% vs 19.3%); compound myopic astigmatism was more common in males (27.4% vs 20.2%). People older than 50 years (p <0.0001) and females (p <0.0001) were more likely to have URE. Ninety-four people accepted FoFo on-site refraction and received SE spectacles; the acceptance was better in the younger (15-29 years old) and literate people (p <0.0001). CONCLUSIONS: URE was the second most common cause of visual impairment in older adults and was higher in females. Within its technological limit, FoFo could be used in the field for correcting URE and obviating the need for travel, thus bridging the know-do gap for the marginalised Dongaria community.

Prevalence and causes of visual impairment in Dongaria indigenous (tribal) community. Tribal Odisha eye disease study # 12.

Purpose: To document the spectrum and magnitude of eye disorders and visual impairment in the Dongaria-a Particularly Vulnerable Tribal Group in the Rayagada district of Odisha, India. Methods: A door-to-door screening protocol included a record of basic health parameters, visual acuity for distance, and near and flashlight examination of the eyes. Spectacles were dispensed to those who improved; those who failed the screening were referred to fixed (primary and secondary) eye care centers. Results: We examined 89% (n = 9872/11,085) of people who consented for screening. The mean age was 25.5 ± 18.8 years; 55% (n = 5391) were female; 13.8% (n = 1361) were under-five children, and 39% (n = 3884) were 6 to 16 years. 86% (n = 8515) were illiterate. 12.4% (n = 1224) were visually impaired, of which 9.9% had early moderate VI, and 2.5% had severe VI and blindness. Uncorrected refractive error was detected in 7.5% (n = 744) and cataracts in 7.6% (n = 754); among the adults, 41.5% (n = 924/2227) had presbyopia. In children, 20% (n = 790) had vitamin A deficiency, 17% (n = 234) had global acute malnutrition, and 18% (n = 244) were stunted for their age. Almost two-thirds (62%, n = 6144) confirmed habitual intake of alcohol, and 4% (n = 389) of adults had essential hypertension. Following the screening, 43.5% (n = 837) of referred patients reported to the fixed centers, and 55% (134/243) of people advised underwent cataract surgery. Spectacles were dispensed to 1496 individuals. Conclusion: Visual impairment and malnutrition are high in Dongaria indigenous community. Permanent health facilities and advocacy would improve this community's health and health-seeking behavior.

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.

Visual function tests for glaucoma practice - What is relevant?

Glaucoma represents one of the most important ocular diseases causing irreversible ganglion cell death. It is one of the most common causes of visual impairment and morbidity in the elderly population. There are various tests for measuring visual function in glaucoma. While visual field remains the undisputed method for screening, diagnosis, and monitoring disease progression, other tests have been studied for their utility in glaucoma practice. This review discusses some of the commonly used tests of visual function that can be routinely used in clinics for glaucoma management. Among the various modalities of testing visual function in glaucoma, this review highlights the tests that are most clinically relevant.

Early changes in host and donor lenticule thickness after Descemet stripping endothelial keratoplasty.

PURPOSE: To analyze the early changes in host and donor lenticule thickness after Descemet Stripping Endothelial Keratoplasty (DSEK). METHODS: DSEK was performed on 32 eyes of 31 patients. Pre- and post- operative slit lamp examination and anterior segment Optical Coherence Tomography (OCT) was done on day-1, day-7, 1 month, and 3 months. RESULTS: There were significant changes in host, lenticule, and total corneal thicknesses between day-1 and day-7, and day-7 and 1 month. There were significant changes in host thickness and total corneal thickness between 1 month and 3 months. Thickness changes were significant between day-1 and day-7, and 1 month and 3 months for thick and thin host, respectively, whereas these changes were observed both for thick and thin host between day-7 and 1 month. Similarly, significant changes were observed between day-7 and 1 month, and day-7 and 1 month in thin lenticule whereas in case of thick lenticule, it was observed till the 3 months follow-up period. There was a significant improvement in visual acuity till the 3 months follow-up period. No significant correlation was observed between visual acuity and host and lenticule thickness. CONCLUSION: The thicknesses of host and lenticule decrease continuously. Lenticule thickness stabilizes before host. Thinner cornea stabilizes earlier compared to thicker cornea.

Tribal Odisha Eye Disease Study # 11 - Particularly vulnerable tribal group eye health program. Program protocol and validation.

Purpose: To describe and validate the eye health program protocol of Dongria tribal community, a particularly vulnerable tribal group (PVTG) in Rayagada district, Odisha, India. Methods: The program would consist of three segments. At people's residences, trained community health workers (CHWs) will measure the vision and collect demographic data. In addition, vision technicians (VTs) will refract using a hand-held device and prescribe spectacles to people who improve to >6/12, N8. Others would be referred to the vision center (VC). At VC, the VT will perform a slit-lamp examination and re-refract. They would refer people with vision ≤6/12 to the secondary center (SC). At SC, referred people will receive a comprehensive eye examination and treatment. The ophthalmologist will assign the cause of blindness and visual impairment for people with visual acuity <6/12. The entire process was rehearsed in a pilot study. Results: The target population is approximately 10,000 people residing in 101 hutments on the hills of Rayagada district. The pilot study included 126 people. The mean age was 44 ± 18 years; 70% of the people were illiterate, and in this cohort, 97.6% (n = 123) had never worn spectacles. In the pilot study, 41% of the people had cataract, and 12% had pterygium. The agreements between optometrist versus VTs and between optometrist versus CHWs were good (k = ~0.8-1.0) in all eye conditions except for strabismus (k = ~0.56-0.65). Conclusion: The pilot study confirms the program modality, and when completed, it would help in the planning and resource allocation of Odisha PVTG eye care.

Does the Accuracy and Repeatability of Refractive Error Estimates Depend on the Measurement Principle of Autorefractors?

Purpose: The purpose of this study was to determine the accuracy and repeatability of refractive errors obtained using three autorefractors based on different measurement principles, vis-à-vis, gold-standard retinoscopy. Methodology: Accuracy of noncycloplegic, sphero-cylindrical refractive error of 234 eyes was obtained using the rotary prism-based RM-8900 closed-field autorefractor, photorefraction based Spot vision screener, wavefront aberrometry based E-see, and streak retinoscopy by four different examiners, masked to the results of each other. Intersession repeatability of autorefractors was determined by repeat measurements in a subset of 40 subjects. Results: Retinoscopy values of M, J0, and J45 power vectors for the cohort ranged from -10.2 to 8 D, -1.4 to 1.8 D, and -0.9 to 1.2 D, respectively. Across autorefractors, the interequipment bias of M and J0 power vectors were statistically insignificant (< ±0.5 D; P > 0.05) but the corresponding limits of agreement were ±2.5 and ±1 D, respectively, without any trend across instruments or the patient's age (P > 0.5). Repeatability of M and J0 power vectors were ±0.75 D and ±0.40 D, respectively, across autorefractors. The range of J45 power vector was too narrow for any meaningful analysis. Conclusions: Refractive errors measured using autorefractors operating on different principles show minimal bias and good short-term repeatability but relatively large agreement limits, vis-à-vis, retinoscopy. Among them, the wavefront aberrometry based E-see autorefractor performs relatively better in all measurement parameters evaluated here. Translational Relevance: Although autorefractor estimates of noncycloplegic refractive error appears independent of their measurement principle, their relatively poor agreement with gold-standard retinoscopy warrants caution while used for screening and quantification of refractive errors.

Automated iris volume analysis and trabecular meshwork length using anterior segment optical coherence tomography - Application in pseudoexfoliation and pseudoexfoliation glaucoma.

Purpose: The aim of this study was to evaluate differences in the iris and angle parameters in psuedoexfoliation syndrome (PXF) and pseudoexfoliation glaucoma (PXG) using anterior segment optical coherence tomography (ASOCT). Methods: Patients with PXF or PXG were compared using ASOCT with primary open-angle glaucoma POAG eyes as controls in this noninterventional comparative study conducted at a tertiary eye care center in East India. All angle parameters, TM length, and iris thickness were analyzed from the enhanced depth imaging (EDI) single scans obtained. Quadrant scans were used for the calculation of iris volume using a custom-built in-house software. In particular, the software performs multiple operations including edge detection, connected components, and thresholding to localize and segment the iris. Differences in the iris volume/thickness and TM length in PXF and PXG with POAG were analyzed. Results: A total of 225 eyes were included, which included 75 PXG and 98 PXF cases and 52 POAG with a mean age of 67 ± 9.7 years at presentation. The algorithm repeatability and reproducibility was also established with correlation coefficients more than 99% which was substantiated with Bland-Altman plots. The iris volume (calculated in 197 images of 225 eyes) did not differ significantly in PXF and PXG eyes, although both had significantly greater volume compared to POAG eyes. The iris volume or other angle parameters including TM length did not correlate with clinical variables such as IOP, age, or visual field indices. Conclusion: Iris parameters or TM length do not explain pathogenesis of glaucoma in pseudoexfoliation.

Scoop and chop - A modified phaco-chop technique for pseudoexfoliation and cataract.

PURPOSE: The purpose is to evaluate the results of the modified direct phaco-chop technique of cataract surgery in eyes with pseudoexfoliation. METHODS: All patients with pseudoexfoliation and visually significant cataract with normal intraocular pressure (IOP) and optic nerve that underwent cataract surgery by the same surgeon using Infiniti®, OZil® Torsional handpiece (Alcon Labs), were included for this retrospective hospital-based study. Direct vertical or horizontal chop technique was used in all cases with parameters set as required for quadrant removal with high vacuum after the initial cleanup of cortex under the capsulorhexis. To allow better visualization of the hardness of the nucleus core, the sides of the lens were scooped out a central well with vacuum with maximum chopping done centrally within the rhexis as the first step to enable better assessment of the depth of burying the chopper for direct chop. Intraoperative details recorded and analyzed included ultrasound time and cumulative dissipated energy. The mean visual acuity and IOP before and after surgery were recorded at 1 day, 1 week, and 1 month. Complications during or after surgery were noted. RESULTS: A total of 138 patients with a mean age of 62 ± 6.7 years underwent phachop technique of phacoemulsification for nuclear cataract grades of nuclear sclerosis 2-4 with significant improvement in visual acuity from baseline (0.26) to 3 months (0.82), P < 0.001. The mean ultrasound torsional amplitude and cumulative dissipated energy (CDE) were greater for brown cataract of grading >3, P = 0.02. A total of 8 patients had intraoperative zonular dialysis in 1 quadrant (none in >1 quadrant), which was not associated with intraoperative vitreous prolapse in 6 eyes. CONCLUSIONS: Direct modified phaco-chop technique may be a safe technique in pseudoexfoliation due to minimal zonular stress with successful outcomes and reduced complications.

Perspectives and impediment to eye care in caregivers of children with childhood glaucoma.

Purpose: To study the perceptions, attitude, knowledge of the disease, and impediments to seeking early eye care in caregivers of children with childhood glaucoma. Methods: The study included new and old children diagnosed with childhood glaucoma (which included congenital glaucoma and developmental glaucoma) at a tertiary hospital of east India. The caregivers were administered a video-based questionnaire through open-ended questions intended to collect demographic and other personal details such as caregiver's socioeconomic status, knowledge, attitude towards eye health, and other social barriers. The responses were analyzed using thematic analysis technique into different buckets such as social status, knowledge/attitude, and sociocultural beliefs while individual responses in each bucket were analyzed. Results: Of a total of 43 patients included,> 75% of patients came from places> 200 km from the eye care centre with> 50% coming from> 300 km. Most patients presented either <1 year (42%, n = 18) or> 3 years (52%, n = 22) with only 2% (n = 3) presenting between 1-3 years of age. The mother was the first person of contact to diagnose the eye abnormality in> 45% of patients. Comparing differences among children who presented within 1 year of first diagnosis and those that presented later, caregivers hailing from long-distance> 200 km from an eye care center, monthly income <5000 INR, and those with social/cultural taboos (like children's eyes should not be operated) were more likely to seek delayed eye care for congenital glaucoma, P < 0.001. Conclusion: Impediments in seeking early eye care for blinding diseases in children (including distance from the nearest hospital, low socioeconomic constraints, and sociocultural beliefs/taboos) mandate serious policies towards improving education about eye disease and eye health among caregivers.

Unusual Surprises in Glaucoma Filtering Surgeries: Lessons Learned and Review of Literature.

PURPOSE: To describe an unusual series of complications after glaucoma filtering surgeries with their clinical findings and outcome after tailored non-conventional modes of therapy. PATIENTS AND METHODS: Eighteen patients who underwent re-interventions (medical or surgical) after glaucoma filtering surgeries during the period at two tertiary centers, excluding those that required conventional modes of treatment (medical control or re-trabeculectomy, simple wound closure for traumatic wound dehiscence, bleb revision or needling, laser iridotomy), were included. Relevant clinical details with intraoperative videos, intraoperative or postoperative problems, and images with course after re-intervention were retrieved from the hospital database. Clinical details which helped in clinching diagnosis and cause for problems and course after intervention with final vision and intraocular pressure were evaluated. RESULTS: Six of 18 eyes required surgical management for an unusual course of events after an uneventful filtering surgery. Bleb morphology and close follow-up of the conjunctiva, in addition to intraocular pressure (IOP) and anterior chamber (AC) configuration, helped diagnose possible aetiology and appropriate tailored management. All patients had good IOP and visual outcome in all except one with macular scar status after retinal detachment surgery. CONCLUSION: Assessment of the bleb morphology in the postoperative course coupled with monitoring of the conjunctival wound are essential to conventional monitoring of IOP and anterior chamber configuration to arrive at appropriate management for rare unusual events after glaucoma surgery.

Unclassified Axenfeld-Rieger Syndrome: A CASE SERIES and Review of Literature.

PURPOSE: To report anterior segment features in unclassified anterior segment dysgenesis with overlapping features of Axenfeld-Rieger syndrome and other developmental anomalies. METHODS: This retrospective study included those with atypical or overlapping features in one or both eyes, which were identified as unclassified ASD. Typical ARS was defined as the presence of posterior embryotoxon with or without iris changes like stromal hypoplasia, corectopia, polycoria, or ectropion uvea with or without systemic features. Cases of ARS with overlapping features with other ASD, like aniridia (complete or incomplete absence of iris), iridocorneal endothelial (ICE) syndrome (beaten metal appearance of corneal endothelium), Peters anomaly, isolated trabeculodysgenesis (evidenced by Haab's striae, buphthalmos, and epiphora) in one or both eyes with other typical ARS features in the same or other eye were included and screened. RESULTS: Of 56 cases of ARS seen over 10 years, a total of 17 eyes of 11 cases (M:F=9:2, unilateral n=3) with unclassified ASD were identified with a median age of patients of 28.45±17.75 years (range 6-30 years). All cases of unclassified ASD had the presence of focal atypical strands of non-progressive anterior synechiae extending from the iris mid-periphery to the cornea with no attachments to the Schwalbe's line in any case. Adjacent keratic precipitates or pigment were present in three eyes with focal beaten metal appearance in one eye. Three patients developed repeated episodes of anterior uveitis in one eye with stromal involvement seen in all cases, which responded to antiviral therapy. CONCLUSIONS: Atypical features like focal strands with differential corneal involvement and onset of viral uveitis in unclassified ARS suggest a possible viral etiology during different periods of eye development.

Viscoless Manual Small Incision Cataract Surgery with Trabeculectomy.

PURPOSE: To compare the efficacy of combined manual small incision cataract and glaucoma surgery with anterior chamber maintainer (ACM) alone versus that with intraoperative viscoelastics. METHODS: Hospital electronic medical records of patients who underwent small incision cataract and trabeculectomy and intraocular lens implantation without Mitomycin-C from 2014 to 2016 were identified from the hospital operation theater database for this retrospective, hospital-based comparative study. All MSICS surgeries were performed by a single surgeon under peribulbar block. Data retrieved from all patients undergoing surgery with viscoelastic (group 2) or under AC maintainer without viscoelastic (group 1) included preoperative visual acuity, preoperative treated intraocular pressure, number of anti-glaucoma medications before surgery, total surgical time, intraoperative complications, postoperative best-corrected visual acuity and IOP at one week and one month, need for additional procedures, and corneal clarity. Differences in surgical time and postoperative course in both groups were compared. RESULTS: Of 268 manual combined cataract and glaucoma surgeries done from 2014-2016, we identified 147 eyes of 130 age-matched patients, which included 51 PACG, 50 POAG, 12 NTG, and 24 PXG eyes with a mean age of 66 ±11.2 years and 64± 10.8 years in group 2 (n=74) and group 1 (n=73), respectively; p=0.9. The surgical time was significantly lower in group 1 (16±4.8 minutes compared to 44±14.6 minutes for group 2; p<0.001) with transient edema seen <1 week after surgery in 24 eyes of group 2 and seven eyes of group 1; p=0.02. The postoperative IOP at all postoperative visits dropped to >50% in both groups with 11 eyes (PXG n=6, PACG n=5) requiring medications for rise in intraocular pressure at a median time of 1.2 months (r=0.2-3 months). The final visual acuity improved >4 snellen lines in all cases with two patients with advanced damage having 1 line improvement in Snellen acuity at final follow-up. CONCLUSION: The ACM can help completely avoid the use of viscoelastic during surgery, which can be an effective technique for MSICS with trabeculectomy in low resource stings. Training for such procedures should be incorporated into residency training programs.

Anatomical Characterization of an Optic Disc Notch Using SD-OCT in Glaucoma.

PURPOSE: To characterize anatomical dimensions of a disc notch using novel methods using spectral domain optical coherence tomography (SD-OCT). PARTICIPANTS: All age- and severity-matched glaucoma patients with disc notch (defined as complete loss of neural rim with no residual rim between disc and cup) seen from 2014 to 2015 who underwent enhanced depth imaging with SD-OCT (Cirrus HD-OCT version 6.5, Carl Zeiss, USA) were included for this retrospective observational study. METHODS: Using known dimensions of the 200 * 200 optic disc cube (6 * 6 mm), the notch width was calculated from the margins of the notch on either side using ImageJ software. The height was calculated from the lowest margin of the cup to the lowest point of the defect on the optic disc. These were compared with the quadrant retinal nerve fiber layer (qRNFT) and sectoral retinal nerve fiber layer (sRNFLT) thickness in notch and the sector 2 clock hours adjacent to the notch region (SaRNFLT). RESULTS: The height and width of the notch in 31 eyes of 27 patients were 2.6 ± 0.48 mm and 2.23 ± 0.31 mm. The RNFL thickness in the same sector as that of the notch was 41 ± 21.06 µm while the adjacent two sectors measured 62 ± 26.5 and 64 ± 26.5 µm on either sides of the sector of the notch. The difference between the sRNFLT and saRNFLT ranged from -9 to 67 and -13 to 50 µm, respectively. This difference was significantly associated with height of the notch (R2 = 20.8, p = 0.01). CONCLUSION: Automated analysis of a notch and RNFL thickness in that sector can help in precise glaucoma monitoring in the region of interest.

Impact of Different Visual Field Instruction Strategies on Reliability Indices.

PURPOSE: To investigate and compare the visual field performance following three different types of visual field instruction strategies. METHOD: Ninety consecutive visual field-naïve glaucoma patients who can perform the test and understand instructions were imparted three forms of instructions prior to the visual field test. Patients with visual acuity <20/200, central corneal opacities, or anterior segment pathology and patients unable to understand general instructions/uncooperative were excluded. All forms of instructions were given by a trained optometrist in the patients' own language as an instruction leaflet read out in 5 min for a verbal group (group1) and by a 5 min video created in house (group 2). Group 3 patients were shown the video first, followed by verbal instructions. We evaluated the reliability parameters in each group after visual field testing by an independent optometrist blinded to the form of instruction given. RESULTS: Among the three groups, group 3 patients had the least number of repeat tests. Eyes with MD<-12Db had better reliability than that of the other groups. Mixed-model linear regression analysis shows that the duration of the test was significantly influenced by the severity of glaucoma in group 1, which is further predisposed by false negatives (FN; ß = 0.06, p < 0.0001, R2 61.7%). CONCLUSION: The video with verbal instruction can minimize the number of repeated tests compared with only verbal or only video instruction medium. The video as well as the combined video/verbal instructions have a practical influence of obtaining more reliable fields compared with only verbal instruction.

Automated retinal nerve fiber layer defect detection using fundus imaging in glaucoma.

Retinal nerve fiber layer defect (RNFLD) provides an early objective evidence of structural changes in glaucoma. RNFLD detection is currently carried out using imaging modalities like OCT and GDx which are expensive for routine practice. In this regard, we propose a novel automatic method for RNFLD detection and angular width quantification using cost effective redfree fundus images to be practically useful for computer-assisted glaucoma risk assessment. After blood vessel inpainting and CLAHE based contrast enhancement, the initial boundary pixels are identified by local minima analysis of the 1-D intensity profiles on concentric circles. The true boundary pixels are classified using random forest trained by newly proposed cumulative zero count local binary pattern (CZC-LBP) and directional differential energy (DDE) along with Shannon, Tsallis entropy and intensity features. Finally, the RNFLD angular width is obtained by random sample consensus (RANSAC) line fitting on the detected set of boundary pixels. The proposed method is found to achieve high RNFLD detection performance on a newly created dataset with sensitivity (SN) of 0.7821 at 0.2727 false positives per image (FPI) and the area under curve (AUC) value is obtained as 0.8733.