Contrast Discrimination and Global Form Perception in Primary Open-Angle Glaucoma and Primary Angle-Closure Glaucoma.

Purpose: This study explored early (contrast discrimination) and intermediate (global form perception) visual processing in primary subtypes of glaucoma: primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). We aimed to understand early and intermediate visual processing in POAG and PACG, matched for similar visual field defect severity. Methods: Early visual processing was measured using a contrast discrimination task described by Porkorny and Smith (1997), and intermediate processing using a global form perception task using glass pattern coherence thresholds. Thresholds were determined centrally and at a single midperipheral location (12.5°) in a quadrant without visual field defects. Controls were tested in corresponding quadrants to individuals with glaucoma. Results: Sixty participants (20 POAG, 20 PACG, and 20 age-matched controls), aged 50 to 77 years, were included. Visual field defects were matched between POAG and PACG, with mean deviation values of -6.53 ± 4.46 (range: -1.5 to -16.85) dB and -6.2 ± 4.24 (range: -1.37 to -16.42) dB, respectively. Two-Way ANOVA revealed significant differences in thresholds between the glaucoma groups and the control group for both contrast discrimination and global form perception tasks, with higher thresholds in the glaucoma groups. Post hoc analyses showed no significant contrast discrimination difference between POAG and PACG, but POAG had significantly higher thresholds than PACG for form perception. Conclusions: In form perception, POAG showed slightly worse performance than PACG, suggesting that individuals with POAG may experience more severe functional damage than PACG of similar visual field severity.

An Insight into Knowledge, Perspective, and Practices of Indian Optometrists towards Childhood Myopia.

The current understanding of clinical approaches and barriers in managing childhood myopia among Indian optometrists is limited. This research underscores the necessity and relevance of evidence-based practice guidelines by exploring their knowledge, attitude, and practice towards childhood myopia. A self-administered internet-based 26-item survey was circulated online among practicing optometrists in India. The questions assessed the demographics, knowledge, self-reported clinical practice behavior, barriers, source of information guiding their management, and extent of adult caregiver engagement for childhood myopia. Of 393 responses, a significant proportion of respondents (32.6-92.4%) were unaware of the ocular complications associated with high myopia, with less than half (46.5%) routinely performing ocular biometry in clinical practice. Despite the growing awareness of emerging myopia management options, the uptake remains generally poor, with single-vision distance full-correction spectacles (70.3%) being the most common mode of vision correction. Barriers to adopting optimal myopia care are medicolegal concerns, absence of clinical practice guidelines, and inadequate consultation time. Own clinical experience and original research articles were the primary sources of information supporting clinical practice. Most (>70%) respondents considered involving the adult caregiver in their child's clinical decision-making process. While practitioners' awareness and activity of newer myopia management strategies are improving, there is plenty of scope for its enhancement. The importance of evidence-based practice guidelines and continuing education on myopia control might help practitioners enhance their clinical decision-making skills.

Design and development of a noninvasive ocular pressure estimator.

SIGNIFICANCE: A snapshot intraocular pressure (IOP) is ineffective in identifying the IOP peak and fluctuation, especially during sleep. Because IOP variability plays a significant role in the progression of glaucoma, monitoring the IOP, especially during sleep, is essential to capture the dynamic nature of IOP. PURPOSE: We aimed to design an ocular pressure estimator (OPE) that can reliably and accurately measure the IOP noninvasively over closed-eyelid condition. METHODS: Ocular pressure estimator works on the principle that the external pressure applied by raising the IOP of the eyeball is transmitted through a compressible septum to the pressure sensor, thus recording the IOP. A fluid-filled pouch with a pressure sensor was placed over a rubber glove mimicking the eyelid (septum), covering the cornea of enucleated goat eyeballs. A pressure-controlled setup was connected to a goat cadaver eye, which was validated by a rebound tonometer. Cannulation of eyeballs through the lower limbus had the least difference from the control setup values documented using rebound tonometer, compared with cannulation through the optic nerve. Intraocular pressures ranging from 3 to 30 mmHg was induced, and the outputs recorded using OPE were amplified and recorded for 10 minutes (n = 10 eyes). We stratified the randomization of the number of times and the induced pressures. RESULTS: The measurements recorded were found to be linear when measured against an IOP range of 3 to 30 mmHg. The device has excellent reliability (intraclass correlation coefficient, 0.998). The repeatability coefficient and coefficient of variations were 4.24 (3.60 to 4.87) and 8.61% (7.33 to 9.90), respectively. The overall mean difference ± SD between induced IOP and the OPE was 0.22 ± 3.50 (95% confidence interval, -0.35 to 0.79) mmHg across all IOP ranges. CONCLUSIONS: Ocular pressure estimator offers a promising approach for reliably and accurately measuring IOP and its fluctuation noninvasively under a condition mimicking a closed eye.

Association of sunlight exposure with visual impairment in an Indian fishing community.

Purpose: Indian fishermen belong to a marginalized population and are continuously exposed to extreme occupational hazards and sunlight. A high prevalence of visual impairment (VI) is reported in the coastal fishing community. We aimed to investigate the association between VI and sunlight exposure measurement (SEM). Methods: In this cross-sectional observational study, 270 eyes of 135 participants were enrolled from a coastal fishing village. Participants underwent a comprehensive ophthalmic examination, which included best-corrected visual acuity (BCVA), and anterior and posterior segment examination. Ocular Surface Disease Index (OSDI) and SEM questionnaire were administered to estimate the level of dry eye and ultraviolet-B (UV-B) exposure, respectively. VI was defined as presenting visual acuity worse than 6/12 (logarithm of the minimum angle of resolution [logMAR] > 0.3). Results: The mean age and spherical equivalent were 50.56 ± 11.72 years (range: 18-80 years) and 0.36 ± 1.68 diopters (D) (range: -7.0 to +3.0 D), respectively. Age, SEM, OSDI, fishing as an occupation, and cataract were significantly associated with higher odds of VI in univariate analysis. Refraction, gender, education level, smoking status, amblyopia, systematic, and other ocular diseases were not significantly associated with VI. In the multivariate analysis, age, SEM, and presence of cataract remained significantly associated with a higher risk for VI. The area under the receiver operating characteristic curve values for age and SEM scores demonstrate a fair index of discrimination for the detection of VI. Conclusion: SEM level is directly associated with a higher risk of VI among fishermen. The fishing community might benefit from regular eye examinations and awareness about the harmful effects of sunlight exposure and preventive measures.

Challenges and impact of COVID-19 lockdown on Indian optometry practice: A survey-based study

Purpose: The Indian government announced a nationwide lockdown as a preventive measure to control the prevailing COVID-19 pandemic. This survey was developed and conducted to assess the impact of lockdown on Indian optometry practice.Methods: A survey questionnaire was designed and circulated across the optometrists practicing in India through multiple social media platforms. All the data were extracted and only valid response were analyzed and reported.Results: A total of 691 optometrists participated in the survey. Most of the participants (22.25%) were in private practice followed by academics (14.89%). Among the valid responses collected, it was found that 43.37% of the respondents were consulting patients during the lockdown. Of these, 27.17% of optometrists were examining infectious cases and 48.68% were examining all the patients who came for consultation. Approximately 50.94% of the participated optometrist had begun telephonic/e‑mail/video consultations. In addition, 64.48% reported that optometrists were at an equal risk of clinching COVID‑19 on comparison with other domains during patient examination. Nearly 30.44% respondents felt that optometrists would face challenges in approaching the patient post COVID-19 considering the close working distance.Conclusion: A proportion of optometrist have switched to some form of teleconsultation in order to aid patients during this prevailing pandemic. Regulatory bodies should issue appropriate guidelines regarding the safe optometry practice for the betterment of both patient and practitioners during face-to-face consultation. (AU)

Physical activity, time spent outdoors, and near work in relation to myopia prevalence, incidence, and progression: An overview of systematic reviews and meta-analyses.

Myopia has reached epidemic levels in recent years. Stopping the development and progression of myopia is critical, as high myopia is a major cause of blindness worldwide. This overview aims at finding the association of time spent outdoors (TSO), near work (NW), and physical activity (PA) with the incidence, prevalence, and progression of myopia in children. Literature search was conducted in PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature, Cochrane Database of Systematic Reviews, ProQuest, and Web of Science databases. Systematic reviews (SR) and meta-analyses (MA) on the TSO, NW, and PA in relation to myopia were reviewed. Methodological nature of qualified studies were evaluated utilizing the Risk of Bias in Systematic Review tool. We identified four SRs out of which three had MA, which included 62 unique studies, involving >1,00,000 children. This overview found a protective trend toward TSO with a pooled odds ratio (OR) of 0.982 (95% confidence interval (CI) 0.979-0.985, I2 = 93.5%, P < 0.001) per extra hour of TSO every week. A pooled OR 1.14 (95% CI 1.08-1.20) suggested NW to be related to risk of myopia. However, studies associating myopia with NW activities are not necessarily a causality as the effect of myopia might force children to indoor confinement with more NW and less TSO. PA presented no effect on myopia. Though the strength of evidence is less because of high heterogeneity and lack of clinical trials with clear definition, increased TSO and reduced NW are protective against myopia development among nonmyopes.

Challenges and impact of COVID-19 lockdown on Indian optometry practice: A survey-based study.

PURPOSE: The Indian government announced a nationwide lockdown as a preventive measure to control the prevailing COVID-19 pandemic. This survey was developed and conducted to assess the impact of lockdown on Indian optometry practice. METHODS: A survey questionnaire was designed and circulated across the optometrists practicing in India through multiple social media platforms. All the data were extracted and only valid response were analyzed and reported. RESULTS: A total of 691 optometrists participated in the survey. Most of the participants (22.25%) were in private practice followed by academics (14.89%). Among the valid responses collected, it was found that 43.37% of the respondents were consulting patients during the lockdown. Of these, 27.17% of optometrists were examining infectious cases and 48.68% were examining all the patients who came for consultation. Approximately 50.94% of the participated optometrist had begun telephonic/e­mail/video consultations. In addition, 64.48% reported that optometrists were at an equal risk of clinching COVID­19 on comparison with other domains during patient examination. Nearly 30.44% respondents felt that optometrists would face challenges in approaching the patient post COVID-19 considering the close working distance. CONCLUSION: A proportion of optometrist have switched to some form of teleconsultation in order to aid patients during this prevailing pandemic. Regulatory bodies should issue appropriate guidelines regarding the safe optometry practice for the betterment of both patient and practitioners during face-to-face consultation.

Behavior of hyperreflective spots noted on optical coherence tomography following intravitreal therapy in diabetic macular edema: A systematic review and meta-analysis.

PURPOSE: Hyperreflective spots (HRS) are considered as spectral domain optical coherence tomography biomarkers in predicting response to intravitreal therapy (IVT) in diabetic macular edema (DME). We aimed to determine if there was a quantitative reduction in HRS following IVT in DME, if the response to antivascular endothelial growth factor (anti-VEGF) drugs was different from steroids, and if HRS-response was associated with improvement in visual acuity (VA) or reduction in central macular thickness (CMT). METHODS: PubMed/MEDLINE, Scopus, ProQuest, CINAHL, Wiley online, and Web of Science were searched (between January 1, 2011 and July 1, 2020). Publication bias and heterogeneity were assessed. Meta-analysis was done using the random-effects model. RESULTS: Totally, 1168 eyes from 19 studies were eligible for inclusion. IVT was associated with a reduction in quantitative HRS (z = -6.3, P < 0.0001). Studies, however, showed heterogeneity (I2 = 93.2%). There was no difference between anti-VEGF and steroid therapies (P = 0.23). The evidence on predicting VA and CMT outcomes were limited by the number of analyzable studies, owing to the wide variation in individual study designs, and lack of randomized controlled trials. CONCLUSION: We could conclude that there is a definite reduction in quantitative HRS following either form of IVT. We highlight the lacunae in the existing literature on HRS in DME and propose goals for future studies to harness the advantage of this promising biomarker.

Functional assessment of the "two-hit" model for neurodevelopmental defects in Drosophila and X. laevis.

We previously identified a deletion on chromosome 16p12.1 that is mostly inherited and associated with multiple neurodevelopmental outcomes, where severely affected probands carried an excess of rare pathogenic variants compared to mildly affected carrier parents. We hypothesized that the 16p12.1 deletion sensitizes the genome for disease, while "second-hits" in the genetic background modulate the phenotypic trajectory. To test this model, we examined how neurodevelopmental defects conferred by knockdown of individual 16p12.1 homologs are modulated by simultaneous knockdown of homologs of "second-hit" genes in Drosophila melanogaster and Xenopus laevis. We observed that knockdown of 16p12.1 homologs affect multiple phenotypic domains, leading to delayed developmental timing, seizure susceptibility, brain alterations, abnormal dendrite and axonal morphology, and cellular proliferation defects. Compared to genes within the 16p11.2 deletion, which has higher de novo occurrence, 16p12.1 homologs were less likely to interact with each other in Drosophila models or a human brain-specific interaction network, suggesting that interactions with "second-hit" genes may confer higher impact towards neurodevelopmental phenotypes. Assessment of 212 pairwise interactions in Drosophila between 16p12.1 homologs and 76 homologs of patient-specific "second-hit" genes (such as ARID1B and CACNA1A), genes within neurodevelopmental pathways (such as PTEN and UBE3A), and transcriptomic targets (such as DSCAM and TRRAP) identified genetic interactions in 63% of the tested pairs. In 11 out of 15 families, patient-specific "second-hits" enhanced or suppressed the phenotypic effects of one or many 16p12.1 homologs in 32/96 pairwise combinations tested. In fact, homologs of SETD5 synergistically interacted with homologs of MOSMO in both Drosophila and X. laevis, leading to modified cellular and brain phenotypes, as well as axon outgrowth defects that were not observed with knockdown of either individual homolog. Our results suggest that several 16p12.1 genes sensitize the genome towards neurodevelopmental defects, and complex interactions with "second-hit" genes determine the ultimate phenotypic manifestation.

Challenges and impact of COVID-19 lockdown on Indian optometry practice: A survey-based study

PURPOSE: The Indian government announced a nationwide lockdown as a preventive measure to control the prevailing COVID-19 pandemic. This survey was developed and conducted to assess the impact of lockdown on Indian optometry practice. METHODS: A survey questionnaire was designed and circulated across the optometrists practicing in India through multiple social media platforms. All the data were extracted and only valid response were analyzed and reported. RESULTS: A total of 691 optometrists participated in the survey. Most of the participants (22.25%) were in private practice followed by academics (14.89%). Among the valid responses collected, it was found that 43.37% of the respondents were consulting patients during the lockdown. Of these, 27.17% of optometrists were examining infectious cases and 48.68% were examining all the patients who came for consultation. Approximately 50.94% of the participated optometrist had begun telephonic/e‑mail/video consultations. In addition, 64.48% reported that optometrists were at an equal risk of clinching COVID‑19 on comparison with other domains during patient examination. Nearly 30.44% respondents felt that optometrists would face challenges in approaching the patient post COVID-19 considering the close working distance. CONCLUSION: A proportion of optometrist have switched to some form of teleconsultation in order to aid patients during this prevailing pandemic. Regulatory bodies should issue appropriate guidelines regarding the safe optometry practice for the betterment of both patient and practitioners during face-to-face

No disponible

Drosophila models of pathogenic copy-number variant genes show global and non-neuronal defects during development.

While rare pathogenic copy-number variants (CNVs) are associated with both neuronal and non-neuronal phenotypes, functional studies evaluating these regions have focused on the molecular basis of neuronal defects. We report a systematic functional analysis of non-neuronal defects for homologs of 59 genes within ten pathogenic CNVs and 20 neurodevelopmental genes in Drosophila melanogaster. Using wing-specific knockdown of 136 RNA interference lines, we identified qualitative and quantitative phenotypes in 72/79 homologs, including 21 lines with severe wing defects and six lines with lethality. In fact, we found that 10/31 homologs of CNV genes also showed complete or partial lethality at larval or pupal stages with ubiquitous knockdown. Comparisons between eye and wing-specific knockdown of 37/45 homologs showed both neuronal and non-neuronal defects, but with no correlation in the severity of defects. We further observed disruptions in cell proliferation and apoptosis in larval wing discs for 23/27 homologs, and altered Wnt, Hedgehog and Notch signaling for 9/14 homologs, including AATF/Aatf, PPP4C/Pp4-19C, and KIF11/Klp61F. These findings were further supported by tissue-specific differences in expression patterns of human CNV genes, as well as connectivity of CNV genes to signaling pathway genes in brain, heart and kidney-specific networks. Our findings suggest that multiple genes within each CNV differentially affect both global and tissue-specific developmental processes within conserved pathways, and that their roles are not restricted to neuronal functions.

Android mobile applications in eye care.

Google Play Store was used to search for eye care-related applications the android simulator using various general terms related to eye care to review and categorize various interactive eye care-related applications in android platform from the details available in the application website. Data collected from application description and application developer's webpage include target audience, category of apps, estimated number of downloads, average user rating, involvement of eye care professionals in developing the application, and cost of the app. All these data were collected only from the details provided in the application website considering on online user perspective and the developers were not contacted to collect any other details. In total, 475 applications were identified and grouped into 13 categories depending on the type of service the application provide. Out of which, only 107 (22.53%) applications had mentioned about the eye care professional involvement in their design or development of the application. The applications were also stratified according to the target audience, and many had no user rating with very few downloads. The lack of evidence-based principles and standardization of application development should be taken into consideration to avoid its negative impact on the community, especially in eye care.