Prevalence of blindness and visual impairment in a coastal region of Southern India: A cross-sectional survey in Prakasam district, Andhra Pradesh.

PURPOSE: To estimate the magnitude, determinants, and causes of visual impairment (VI) and blindness among people >40 years. METHODS: In this cross-sectional survey, 2,968 people >40 years from 34 clusters were examined. A cluster random sampling method with a compact segment sampling technique was used to select the study participants. Prevalence of any VI (presenting visual acuity (PVA) <6/12 in better eye), severe VI (PVA <6/60 - 3/60), and blindness (PVA <3/60 in better eye) were expressed as percentage with 95% confidence interval. Logistic regression was performed to determine the risk factors associated with blindness. A P value of less than 0.05 was considered statistically significant. RESULTS: The mean age of the participants was 54.6 years (Standard deviation ± 11.2 years). The prevalence of mild, moderate, and severe visual impairment was 14.2% (12.95-15.49), 13.7% (12.46-14.97), and 0.7% (0.47-1.12), respectively. The prevalence of blindness was 1.3% (0.94-1.79, n = 39). The overall prevalence of VI (presenting Visual Acuity <6/12) was 12.0% (95% CI: 10.8-13.2%). The major causes of VI were cataract (78.08%), refractive error (12.07%), and optic atrophy (2.22%), and corneal opacity (2.22%) and the major cause of blindness was cataract (77.27%). Blindness was strongly associated with increasing age- OR 17.1 (95% CI: 4.9-59.8) for people >70 years, and OR 7.6 (95% CI: 2.2-26.5) for people aged between 60 and 69 years compared to those aged 41-50 years and people living near coastal regions (Within 50 km of coast) (OR: 3.9, 95% CI: 1.6-7.3). CONCLUSION: Blindness and vision impairment are of public health concern in this geographic region. Eye care services need to be augmented to address this challenge.

Identifying causes of vision loss and assistive technology needs among patients attending rehabilitation clinic of a tertiary care center in North India.

PURPOSE: Investigating the causes of visual loss and the best corrected visual acuity (BCVA) is crucial for identifying avoidable eye problems and planning appropriate rehabilitation and assistive technology (AT) services. The study aimed to identify various causes of vision loss and determine AT required for vision rehabilitation (VR). METHODS: The electronic records of patients who attended the VR clinic at a tertiary eyecare for the past 2 years were reviewed. Information such as demographics, BCVA, and causes of visual impairment were retrieved from the records. BCVA was categorized into better than or equal to 1/60 and less than <1/60 for AT services. RESULTS: In total, 1723 patients, mostly male (71.2%), visited the rehabilitation clinic from 2018 to 2019. Around 58.6% of patients belonged to the age group 16-49 years, whereas 25.6% were less than 15 years old. The most frequent eye problems were retinal disorders (63.5%), followed by retinitis pigmentosa (15.2%) and rod-cone dystrophy (4.7%). In contrast, congenital disorders were the most common cause of vision loss among younger groups. Approximately 36.0% of patients had <1/60 blindness and 16.6% had ≥1/60. Around 17.1% of patients would benefit from large prints (near vision acuity N18-N12). CONCLUSION: Early detection and timely management will prevent a significant proportion of patients from developing irreversible vision loss. Around one-third of patients would benefit from visual substitution AT.

Harnessing the medical undergraduate human resource for screening of sight-threatening diabetic retinopathy.

PURPOSE: To assess whether medical undergraduates can be trained to effectively screen diabetic retinopathy (DR) by statistical comparison with a retina specialist at a tertiary eye care center in India. METHODS: Three final-year undergraduate medical students, having completed ophthalmology department rotation, received training from a retina specialist for grading DR, following which they were asked to grade a set of 50 fundus photographs centered on the macula with a view of 50° as sight-threatening DR (STDR), diabetic macular edema, and grade of DR. Agreement among the undergraduates and retina specialist was determined with the help of Cohen's Kappa coefficient. RESULTS: Kappa coefficient between undergraduates for detection of STDR ranged from 0.695 to 0.817 and between each student and the retina specialist ranged from 0.663 to 0.712. The sensitivity and specificity for undergraduates' and retina specialist's detection of STDR were 93.93%-96.96% and 60%, respectively. CONCLUSION: There was substantial agreement among the undergraduates as well as between the undergraduates and the retina specialist for the detection of STDR. Undergraduates also detected STDR with a high sensitivity. This study outlines the feasibility of training undergraduate students for screening DR.

Biomechanical properties of cornea and ocular aberrations in myopic eyes.

PURPOSE: To study the correlation of corneal topography, corneal biomechanical properties, and ocular aberrations with the magnitude of refractive error in myopic eyes. METHODS: All myopic patients attending the clinic for refractive surgery were recruited. Data recorded included visual acuity, axial length (AL), central corneal thickness (CCT), manifest refraction spherical equivalent (MRSE), topography (Pentacam - Oculus), corneal biomechanical factors [ocular response analyzer (ORA)], and optical aberrations (iTrace). They were further categorized into group 1 (suitable for femto-LASIK) and group 2 (unsuitable for femto-LASIK). RESULTS: Sixty eyes (30 myopes) of mean age 22.78 ± 2.71 years were enrolled. A negative correlation of refractive error was noted with AL (ρ = -0.9; P < 0.001), total aberrations (ρ = 0.53; P < 0.001), and lower-order aberrations (LOA) (ρ = 0.54; P < 0.001). A strongly positive correlation was noted between CCT and corneal hysteresis (CH) (ρ = 0.63; P < 0.001), CCT and CRF (ρ = 0.56; P < 0.001), CH and corneal resistance factor (CRF) (ρ = 0.83; P < 0.001), and Goldmann equivalent intraocular pressure (IOPg) and corneal compensated intraocular pressure (IOPcc) (ρ = 0.78; P < 0.001). An increase in higher-order aberrations (HOAs) as well as lower-order aberrations (LOAs) was noted with increasing sim-K [HOA (r = 0.73, P = 0.001); LOA (r = 0.601, P = 0.014)] and increasing CRF [HOA (r = 0.5, P = 0.006); LOA (r = 0.732, P = 0.001)] in group 2. The amount of refractive error, axial length, central corneal thickness, and sim-K were significantly different in the two groups. CONCLUSION: Increasing degree of myopia is associated with an increase in axial length, total aberrations, and lower-order aberrations. Corneal biomechanical parameters have a strong correlation with each other. Lower corneal biomechanics are noted in high myopes as they have weaker and thinner corneas. Corneal biomechanics and ocular aberrations do not differ significantly between cases suitable for femto-LASIK and cases unsuitable for femto-LASIK.

COVID and COVID vaccine-related corneal morbidity: A review.

Systemic coronavirus disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has had several ocular consequences. Many vaccines have been developed against the disease, with adverse events being reported as well. Various ocular adverse events secondary to coronavirus disease 2019 (COVID-19) vaccines have also featured in literature in recent times. This review features the reported corneal-related effects of COVID infection and vaccination. These include direct effects on corneal grafts and unilateral or bilateral corneal melts. The compilation of reported experiences from across the world in this systematic review will help clinicians recognize the possible presentations, pathogenesis, and management of the same.

Tear Tacrolimus Levels and Clinical Response After Adjunct Therapy With Cutaneous Application of Tacrolimus 0.1% Over Upper Eyelid Skin in Chronic Vernal Keratoconjunctivitis.

PURPOSE: The aim of this study was to evaluate the role of cutaneous application of 0.1% tacrolimus eye ointment over the skin of the upper eyelid in chronic vernal keratoconjunctivitis (VKC). METHODS: A prospective, longitudinal, noncomparative, open-label clinical study of moderate-to-severe grade steroid-dependent VKC was performed. Study participants were initiated on adjunct therapy of cutaneous application of 0.1% tacrolimus ointment twice daily on the upper eyelid skin. Ocular surface evaluation parameters, meibomian gland imaging, intraocular pressure, visual acuity, and clinical disease severity scoring were performed to assess clinical response at baseline and month 3 of therapy. Tear levels of tacrolimus were measured at month 3 using high-performance liquid chromatography tandem mass spectrometry and correlated with the clinical score. RESULTS: Palpebral form of VKC was observed in 85% of the cases, with positive family history in 5%, atopy in 7.5%, and keratoconus in 11.25%. Clinical assessment revealed improvement in 97.5% patients with discontinuation of concomitant topical steroids in 64% of patients. There were no changes in visual acuity, intraocular pressure, or ocular surface evaluation after therapy. Tacrolimus was detected in the tears of all our study patients after cutaneous application over the upper eyelid skin, proving its bioavailability with mean tear tacrolimus levels of 6.55 ± 21.43 ng/mL. Correlation analysis revealed a moderate negative correlation between the clinical score and tacrolimus concentration (Spearman correlation coefficient: -0.34, P = 0.002). CONCLUSIONS: Cutaneous tacrolimus 0.1% ointment over the upper eyelid skin is an efficacious alternative method of application in treatment of VKC, with no resultant ocular irritation.

Developing Standard Treatment Workflows-way to universal healthcare in India.

Primary healthcare caters to nearly 70% of the population in India and provides treatment for approximately 80-90% of common conditions. To achieve universal health coverage (UHC), the Indian healthcare system is gearing up by initiating several schemes such as National Health Protection Scheme, Ayushman Bharat, Nutrition Supplementation Schemes, and Inderdhanush Schemes. The healthcare delivery system is facing challenges such as irrational use of medicines, over- and under-diagnosis, high out-of-pocket expenditure, lack of targeted attention to preventive and promotive health services, and poor referral mechanisms. Healthcare providers are unable to keep pace with the volume of growing new scientific evidence and rising healthcare costs as the literature is not published at the same pace. In addition, there is a lack of common standard treatment guidelines, workflows, and reference manuals from the Government of India. Indian Council of Medical Research in collaboration with the National Health Authority, Govt. of India, and the WHO India country office has developed Standard Treatment Workflows (STWs) with the objective to be utilized at various levels of healthcare starting from primary to tertiary level care. A systematic approach was adopted to formulate the STWs. An advisory committee was constituted for planning and oversight of the process. Specialty experts' group for each specialty comprised of clinicians working at government and private medical colleges and hospitals. The expert groups prioritized the topics through extensive literature searches and meeting with different stakeholders. Then, the contents of each STW were finalized in the form of single-pager infographics. These STWs were further reviewed by an editorial committee before publication. Presently, 125 STWs pertaining to 23 specialties have been developed. It needs to be ensured that STWs are implemented effectively at all levels and ensure quality healthcare at an affordable cost as part of UHC.

Corneal blindness and eye banking: Current strategies and best practices.

Corneal blindness (CB) is one of the leading causes of blindness in India and globally, affecting around 8 million population worldwide. Many of these corneal blind patients may be visually rehabilitated by corneal transplantation (CT). Eye banking plays a crucial role in facilitating CT and ocular research. Many countries have adopted regulatory frameworks, quality assurance programs, and technological advancements to enhance the efficacy and safety of CT. Various infrastructural and organizational frameworks of eye banks (EBs) in India, according to the Eye Bank Association of India (EBAI), aid in establishing guidelines and standards for EB practices. Initiatives such as the National Programme for Control of Blindness (NPCB) have significantly contributed to eye donation rates and improved access to donor corneas. This review article discusses the established eye banking networks in countries such as India, the United States (USA), and Europe, where dedicated EB organizations work collaboratively to ensure efficient procurement, processing, and distribution of corneal tissue. It also highlights specific strategies employed in India and global countries to address EBs' challenges. These challenges include the shortage of donor corneas, improving donor screening and tissue processing techniques, ensuring timely distribution of corneal tissue, and maintaining high-quality standards. Interestingly, the comparative analysis between India and other developed countries highlights the similarities and differences in eye banking strategies. By understanding the strategies employed by different regions, EBs can learn from each other's experiences and work toward achieving optimal outcomes in CT and ocular research worldwide. It underscores the importance of knowledge sharing and collaborative efforts in addressing common challenges and implementing best practices in eye banking.

Comparative evaluation of intraoperative aberrometry and Barrett's toric calculator in toric intraocular lens implantation.

Purpose: Barrett toric calculator (BTC) is known for its accuracy in toric IOL (tIOL) calculation over standard calculators; however, there is no study in literature to compare it with real-time intraoperative aberrometry (IA). The aim was to compare the accuracy of BTC and IA in predicting refractive outcomes in tIOL implantation. Methods: This was an institution-based prospective, observational study. Patients undergoing routine phacoemulsification with tIOL implantation were enrolled. Biometry was obtained from Lenstar-LS 900 and IOL power calculated using online BTC; however, IOL was implanted as per IA (Optiwave Refractive Analysis, ORA, Alcon) recommendation. Postoperative refractive astigmatism (RA) and spherical equivalent (SE) were recorded at one month, and respective prediction errors (PEs) were calculated using predicted refractive outcomes for both methods. The primary outcome measure was a comparison between mean PE with IA and BTC, and secondary outcome measures were uncorrected distance visual acuity (UCDVA), postoperative RA, and SE at one month. SPSS Version-21 was used; P < 0.05 considered significant. Results: Thirty eyes of 29 patients were included. Mean arithmetic and mean absolute PEs for RA were comparable between BTC (-0.70 ± 0.35D; 0.70 ± 0.34D) and IA (0.77 ± 0.32D; 0.80 ± 0.39D) (P = 0.09 and 0.09, respectively). Mean arithmetic PE for residual SE was significantly lower for BTC (-0.14 ± 0.32D) than IA (0.001 ± 0.33D) (-0.14 ± 0.32D; P = 0.002); however, there was no difference between respective mean absolute PEs (0.27 ± 0.21 D; 0.27 ± 0.18; P = 0.80). At one-month, mean UCDVA, RA, and SE were 0.09 ± 0.10D, -0.57 ± 0.26D, and -0.18 ± 0.27D, respectively. Conclusion: Both IA and BTC give reliable and comparable refractive results for tIOL implantation.

A Framework for the Continuous Evaluation of 3D Motion Perception in Virtual Reality.

OBJECTIVE: We present a novel framework for the detection and continuous evaluation of 3D motion perception by deploying a virtual reality environment with built-in eye tracking. METHODS: We created a biologically-motivated virtual scene that involved a ball moving in a restricted Gaussian random walk against a background of 1/f noise. Sixteen visually healthy participants were asked to follow the moving ball while their eye movements were monitored binocularly using the eye tracker. We calculated the convergence positions of their gaze in 3D using their fronto-parallel coordinates and linear least-squares optimization. Subsequently, to quantify 3D pursuit performance, we employed a first-order linear kernel analysis known as the Eye Movement Correlogram technique to separately analyze the horizontal, vertical and depth components of the eye movements. Finally, we checked the robustness of our method by adding systematic and variable noise to the gaze directions and re-evaluating 3D pursuit performance. RESULTS: We found that the pursuit performance in the motion-through depth component was reduced significantly compared to that for fronto-parallel motion components. We found that our technique was robust in evaluating 3D motion perception, even when systematic and variable noise was added to the gaze directions. CONCLUSION: The proposed framework enables the assessment of 3D Motion perception by evaluating continuous pursuit performance through eye-tracking. SIGNIFICANCE: Our framework paves the way for a rapid, standardized and intuitive assessment of 3D motion perception in patients with various eye disorders.

Ocular conjunctival microbiome profiling in dry eye disease: A case control pilot study.

Purpose: Keratoconjunctivitis sicca (KCS) or dry eye disease (DED) is a multifactorial disease that results in discomfort, visual disturbance, and tear film instability with potential damage to the ocular surface. A pilot study was undertaken to determine if there were any major substantial differences in the ocular microbiome in DED patients versus healthy controls. Methods: The bacterial communities residing in the conjunctiva of patients with DED (n = 4) and healthy controls (n = 4) were assessed by 16S ribosomal RNA (rRNA) gene sequencing of the V4-V5 region. Results: The phyla Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were most dominant and accounted for 97% and 94.5% of all bacterial sequences in patients and controls, respectively. At the genus level, 27 bacterial genera were found with more than two-fold difference between patients and controls. Four of these - Acinetobacter, Corynebacterium, Lactobacillus, and Pseudomonas spp. - dominated the ocular microbiome of all subjects, but were proportionately lower in DED (16.5%) compared to controls (37.7%). Several bacterial genera were found to be unique in DED (34) and controls (24). Conclusion: This pilot study is an attempt to profile the ocular microbiome in patients with DED that demonstrated a higher concentration of microbial DNA compared to controls, with Firmicutes phyla dominating the bacterial population in patients with DED.

Evaluation of liposomal amphotericin B for the treatment of fungal keratitis in a tertiary eye care hospital.

Purpose: To evaluate the efficacy of liposomal amphotericin B (L-AMB) for the treatment of fungal keratitis. Methods: Patients with fungal keratitis confirmed by potassium hydroxide (KOH) smear and/or confocal microscopy were administered topical L-AMB and randomized into three groups treated with three different formulations. The medication was administered two hourly till clinical improvement was achieved, followed by six hourly till complete resolution. The outcome measures were time to clinical improvement, resolution of epithelial defect, stromal infiltrate, hypopyon, extent and density of corneal opacity, neovascularization, and best corrected visual acuity (BCVA) at 3 months. Results: Mean age of the patients was 46.6 ± 14.8 years, and trauma with vegetative matter was the most common predisposing factor. Aspergillus flavus (36%) was the most common fungus cultured, followed by Fusarium (23%). Mean time to clinical improvement, time to resolution of epithelial defect, mean time to resolution of infiltrate, and time to resolution of hypopyon were 3.45 ± 1.38, 25.35 ± 8.46, 37.97 ± 9.94, and 13.33 ± 4.90 days, respectively, and they were comparable among the three groups. There was a significant difference between treatment failure and success cases in terms of days of presentation (P < 0.01), size of the epithelial defect (P-value 0.04), and infiltrate size at presentation (P-value 0.04). At 3 months follow-up, no statistically significant difference was noted in BCVA and mean scar size among groups. Conclusion: L-AMB in a gel form is an effective antifungal agent that promotes the healing of fungal ulcers with notably least vascularization and better tolerance. Trial registration number: CTRI/2020/04/024550.

Prevalence and causes of low vision in a population-based study on childhood visual impairment in North India (CHVI 4).

Purpose: The present study was a population-based study to determine the prevalence and causes of low vision in children less than 16 years in North India. Methods: This cross-sectional study was conducted in 40 clusters of urban Delhi. Children aged less than 16 years underwent visual acuity screening using age-appropriate visual acuity charts. All children with visual acuity of <6/12 in any eye in the age group between 3 and 15 years and inability to follow the light in age less than 3 years were referred for detailed ophthalmic examination in a centrally based clinic. Cycloplegic examination and best-corrected visual acuity (BCVA) were assessed. They were examined by an ophthalmologist to determine the prevalence and causes of functional low vision (FLV). The prevalence of FLV was compared with other population-based studies across India and other parts of the world. Results: Amongst 20,955 children examined for visual acuity, 789 children were referred to the central clinic for detailed ophthalmic examination. The overall prevalence of low vision was 0.62 per 1,000 children (95% confidence interval [CI] 0.12-1.90). The main anatomical cause of low vision was retinal abnormalities. Conclusion: Although the prevalence of children with low vision decreased as compared to previous population-based studies. There is an important need to create awareness among parents on appropriate and timely usage of low-vision devices (LVDs) at an affordable cost to improve the visual quality in children with low vision.

Stereopsis following surgery in children with congenital and developmental cataracts: A systematic review and meta-analysis.

We estimated the proportion of children with stereopsis following surgery in congenital and developmental cataracts by systematic review and meta-analysis and also considered the factors influencing stereopsis, such as intervention age and presence of strabismus. Stereopsis is directly related to quality of life, and investigating its levels following cataract surgery in children may help decide the right time to intervene, particularly in the context of brain plasticity. We conducted a systematic literature search using Scopus, PubMed, and Web of Science and found 25 case series, 3 cohorts, and 3 clinical trial studies from 1/1/1995 to 31/12/2020. Study-specific proportions of stereopsis from 923 children were pooled using a random-effects model, and stratified analyses were conducted based on intervention age and pre-existing strabismus as a confounder. We appraised the risk of bias using tools published by National Institutes of Health and evaluated publication bias with funnel plots and the Egger test. The pooled proportions of stereopsis based on 8 unilateral and 6 bilateral congenital cataract studies were 0.37 (95% CIs: [0.24, 0.53]) and 0.45 (95% CIs: [0.24,0.68]) when patients with preexisting strabismus were excluded as a confounder. When the intervention age was ≤6 months, proportions in unilateral congenital cataract group significantly increased to 0.52 (95% CIs: [0.37, 0.66]; P = 0.49) compared to 0.26 (95% CIs: [0.14, 0.44]; P = 0.16) otherwise. A similar increase in proportions was found when intervention age ≤4 months. In both unilateral and bilateral congenital cataract groups, proportions increased significantly when the confounder was excluded. Overall, proportions in bilateral congenital cataracts were significantly greater than unilateral cases (irrespective of confounder). Eight unilateral and 5 bilateral developmental cataract studies resulted in pooled proportions of 0.62 (95% CIs: [0.27, 0.88] and 0.82 (95% CIs: [0.4, 0.97]), respectively. Although proportions for bilateral developmental cataracts were greater than unilateral cataracts (irrespective of confounder), results were not statistically significant. Finally, proportions in unilateral developmental cataracts were significantly greater than unilateral congenital cataracts (Z = 7.413, P = 6.173694e-14). We conclude that surgical intervention within first 4-6 months can significantly affect postoperative outcomes in unilateral congenital cataracts. Analysis of existing data does not show a significant effect of intervention age on stereopsis outcomes for developmental cataracts.

Population-based study on the prevalence, clinical characteristics and vision-related quality of life in patients with corneal opacity resulting from infectious keratitis: results from the Corneal Opacity Rural Epidemiological study.

AIM: To estimate prevalence and characterise clinical features and vision-related quality of life (VR-QoL) of corneal opacities (COs) resulting from infectious keratitis in a rural North Indian population. METHODS: The Corneal Opacity Rural Epidemiological study was a cross-sectional study conducted in 25 randomly selected clusters of rural Gurgaon, Haryana, India to determine prevalence of corneal disease across all age groups. During house-to-house visits, sociodemographic details, presence, type and clinical characteristics of corneal disease, laterality and resultant visual impairment (VI) was noted. Subgroup analysis of data was performed to understand the prevalence, clinical characteristics, VR-QoL in patients with CO due to infectious keratitis. VR-QoL scores were compared with healthy controls. RESULTS: Overall, 65 of 12 113 participants had evidence of infectious keratitis-related CO with a mean age of 63.3 (±14.7 SD) years. Prevalence of infectious keratitis-related CO, including both bilateral (12/65) and unilateral (53/65) cases was 0.54% (95% CI 0.41 to 0.66) seen in a total of 77 eyes of 65 participants. Mean visual acuity was 1.18±0.80 with 30/77 (38.9%) eyes having a presenting visual acuity <3/60. Most of the CO due to infectious keratitis was <3 mm in size (61.03%; 47/77), nebular (42.85%; 33/77) and central (49.35%; 38/77) in location. These participants had significantly higher VR-QoL scores and hence poorer VR-QoL across all three domains of vision function (scores of 28 vs 22, 7.5 vs 5 and 15.5 vs 9, respectively; p<0.0001) when compared with healthy controls. CONCLUSION: The data from this study give an insight into the burden and clinical characteristics of COs resulting from infectious keratitis. VR-QoL is significantly impaired in patients with CO resulting from infectious keratitis, both in bilateral and unilateral cases.

Distribution of TGFBI variants in patients with early onset glaucoma.

Purpose: To describe a novel association of TGFBI variants with congenital glaucoma in a family with GAPO (growth retardation, alopecia, pseudoanodontia, and progressive optic atrophy) syndrome, as well as among other unrelated cases of juvenile onset open-angle glaucoma (JOAG) and primary congenital glaucoma (PCG). Methods: This study of one family of GAPO with congenital glaucoma and three unrelated patients with JOAG analyzed a common link to glaucoma pathogenesis. Three girls with GAPO syndrome born to consanguineous parents in a multi-generation consanguineous family were identified. Two of the girls had congenital glaucoma in both eyes, while the elder sibling (a 10-year-old female) had features of GAPO syndrome without glaucoma. Results: A genetic evaluation using whole exome sequencing revealed a novel homozygous ANTXR1 mutation in all three affected siblings with GAPO. No other mutations were detected in the genes associated with glaucoma. A rare missense variant in the TGFBI gene was shared in the two siblings with congenital glaucoma and GAPO syndrome. We found three other unrelated patients with JOAG and one patient with primary congenital glaucoma with no known glaucoma causing gene mutations, but having four different missense variants in the TGFBI gene. One of these patients with JOAG had familial granular corneal dystrophy. Molecular dynamic simulations of TGFBI and 3-D structural models of three of its variants showed significant alterations that could influence TGFBI protein function. Conclusions: The possibility that variations in the TGFBI gene could have a possible role in the pathogenesis of congenital and juvenile onset open-angle glaucomas needs further evaluation.

Mucopolysaccharidosis.

Mucopolysaccharidosis are group of inherited metabolic diseases caused by the absence or malfunctioning of lysosomal enzymes resulting in accumulation of glycosaminoglycans. Over time this accumulation damages cells, tissues, and organs. There are seven types of MPS and 13 subtypes that are associated with multiple organ systems, such as the respiratory, liver, spleen, central nervous systems, arteries, skeletons, eyes, joints, ears, skin, and/or teeth. The various types share some common ocular features that differ in terms of the severity of the affection. Visual loss in MPS patients is varied and can be due to corneal clouding, glaucoma, retinopathy, and optic neuropathy. The primary focus of this review is on changes in the cornea and anterior segment in MPS patients, including clinical and novel investigative modalities, current surgical management, effects of systemic therapy like hematopoietic stem cell transplants (HSCT)and enzyme replacement therapy (ERT), as well as significant research developments.

Clinical and diagnostic imaging profile of three anterior segment dysgenesis disorders presenting with infantile corneal opacities.

PURPOSE: To describe three anterior segment dysgenesis disorders with infantile corneal opacities, namely, congenital hereditary endothelial dystrophy (CHED), primary congenital glaucoma (PCG), and Peters anomaly (PA) in terms of clinical characteristics, histopathology, genetic association, and diagnostic imaging profiles using imaging modalities such as ultrasound biomicroscopy (UBM) and microscope-integrated intraoperative optical coherence tomography (i-OCT). MATERIALS AND METHODS: Seventy-four eyes with 22 eyes of CHED, 28 eyes of PA, and 24 eyes of PCG were clinically evaluated and underwent imaging using UBM and i-OCT. Corneal buttons of 16 operated patients underwent histopathological analysis, while genetic analysis was done in 23 patients using whole-exome sequencing. RESULTS: Corneal diameters (CD) and UBM parameters like anterior chamber depth (ACD), iris thickness (IT), and ciliary body (CB) thickness revealed a statistically significant difference between the three categories. In PA, 9 eyes had a third rare phenotype with only a posterior corneal defect with no iris adhesions. Genetic mutations were seen in all tested patients with CHED, in 83.3% of patients with PCG, and in 80% of patients with the third type of PA. i-OCT helped in the characterization of corneal opacity, identification of posterior corneal defects, iridocorneal adhesions, and contour of Descemet's membrane. CONCLUSION: Overlapping phenotypes of the above disorders cause a diagnostic dilemma and parameters like CDs, UBM ACD, IT, and CB thickness help differentiate between them. i-OCT can help in classifying the diseases in a high resolution, non-contact manner, and can better delineate corneal characteristics. The rare third type of PA phenotype may have a genetic association.

Prospective audit of the phenotype, causes and correlates of trachomatous and non- trachomatous trichiasis in a peri-elimination setting.

PURPOSE: To explore the burden, clinical features and associations of trichiasis due to trachomatous and non-trachomatous aetiologies. METHODS: Consenting patients presenting with trichiasis of either eyelid (of one or both eyes) attending the outpatient department, cornea and oculoplasty clinics of a tertiary eye care hospital in New Delhi between August 2018 to March 2020 were included. A comprehensive examination including visual acuity and anterior segment evaluation and photography was performed. Grade of trichiasis, laterality, presence and grade of entropion, and information on corneal opacity, conjunctival scarring, Herbert's pits, and pannus, if present, were recorded in the case record form. RESULTS: Overall, 302 patients (454 eyes) with trichiasis were recruited. The most common attributed cause of upper eyelid trichiasis (276 patients, 405 eyes) was trachoma (26% of patients), followed by Stevens-Johnson syndrome (23%), blepharokeratoconjunctivitis (17%) and old age (10%). A total of 296/405 eyes (73%) had some form of corneal involvement. Trachoma was not identified as the cause of trichiasis in any eye with lower eyelid-only disease. CONCLUSION: Only about a quarter of upper eyelid trichiasis in this peri-elimination setting was attributed to trachoma. A distinction between trachomatous and non-trachomatous trichiasis is imperative to meaningfully determine whether elimination of trachoma as a public health problem has occurred. These data may have implications for population-based estimates of TT prevalence in India and other peri-elimination settings.