Optometry and Vision Sciences - Research Publications

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    THE LIMITED LEVEL OF DIGITAL SKILLS AND COMPETENCIES OF OPTOMETRY STUDENTS
    Nguyen, KP ; Luke, AK ; Cheng, Y ; John, A ; Cham, KM (INFORMING SCIENCE INST, 2022-01-01)
    Aim/Purpose: Digital health is increasingly being utilized in clinical practice given its ease of accessibility, but it lacks emphasis from universities and accreditation bodies. This study attempted to better understand the digital capabilities of optometry students. Background: With technological advancements transforming the Australian workforce and healthcare, there is a growing demand for digitally competent graduates. This study investigated digital perceptions and preferences of optometry students relating to their studies and readiness for work in healthcare. Methodology: Current optometry students participated in an anonymous online survey. Questions were designed to evaluate their understanding and awareness of digital skills and competencies for learning whilst at university, and for use in the health sector workforce. Results were analyzed to underscore key trends and answers to open-ended questions underwent inductive thematic analysis to generate themes for discussion. Contribution: Optometry educators can bridge the gap in digital practices between students and the workplace by obtaining a baseline of their capabilities and incorporating specific activities within the curriculum to increase student awareness and support their understanding and development in this aspect. Findings: Most students were confident in using daily technologies for learning. Reference management software was perceived to be most important and useful skill to attain. While students were less confident in creating applications, they were keen to learn even though it seemed peripheral to their career and professional development. 70% of the students knew how to manage their online privacy and security. Of the students, 92% highlighted that attaining competency in digital skills would enhance their career and professional development, but only 54% believed they possessed the relevant skills for entering the workforce. Only 19% of the students reported having sufficient university support. Recommendations for Practitioners: Digital capabilities of learners do need to be taught explicitly and should not be assumed. To improve student learning outcomes, digital skills and competencies need to be embedded throughout the curriculum and addressed through learning objectives. Recommendation for Researchers: More work needs to be done in implementing digital training and services at a subject, course, and institutional level. Some international benchmarking of optometry curricula and optometry research would clarify the need for digital education, to educators and students alike. Impact on Society: Currently, there is a lack of recognition of digital health by accrediting bodies, thus preventing digital competency from being a priority in the curriculum of schools. There is a further need to establish dialogue between universities, employers, and accrediting bodies to set consistent and realistic expectations of digital skills and competencies. Future Research: Future studies should consider having larger sample sizes to observe similarities and differences in digital capabilities between year levels. Student focus groups and interviews can be performed to better understand the rationale behind the desire and interest to learn digital technologies that seemed irrelevant to optometry.
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    Developing a Screening Tool for Areas of Abnormal Central Vision Using Visual Stimuli With Natural Scene Statistics
    Srinivasan, R ; Turpin, A ; McKendrick, AM (ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 2022-02-01)
    PURPOSE: Previous studies show that some visual field (VF) defects are detectable from visual search behavior; for example, when watching video. Here, we developed and tested a VF testing approach that measures the number of fixations to find targets on a background with spatial frequency content similar to natural scenes. METHODS: Twenty-one older controls and 20 people with glaucoma participated. Participants searched for a Gabor (6 c/°) that appeared in one of 25 possible locations within a 15° (visual angle) 1/f noise background (RMS contrast: 0.20). Procedure performance was assessed by calculating sensitivity and specificity for different combinations of control performance limits (p = 95%, 98%, 99%), number of target locations with fixations outside control performance limits (k = 0 to 25) and number of repeated target presentations (n = 1 to 20). RESULTS: Controls made a median of two to three fixations (twenty-fifth to seventy-fifth percentile: two to four) to locate the target depending on location. A VF was flagged "abnormal" when the number of fixations was greater than the p = 99% for k = 3 or more locations with n = 2 repeated presentations, giving 85% sensitivity and 95.2% specificity. The median test time for controls was 85.71 (twenty-fifth to seventy-fifth percentile: 66.49-113.53) seconds. CONCLUSION: Our prototype test demonstrated effective and efficient screening of abnormal areas in central vision. TRANSLATIONAL RELEVANCE: Visual search behavior can be used to detect central vision loss and may produce results that relate well to performance in natural visual environments.
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    Stem cell therapies for eye conditions: A survey of Australian ophthalmologists
    Cabrera-Aguas, M ; Downie, L ; Munsie, MM ; Watson, SL (WILEY, 2022-02-01)
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    Evaluating the clinical translational relevance of animal models for limbal stem cell deficiency: A systematic review
    Delic, NC ; Cai, JR ; Watson, SL ; Downie, LE ; Di Girolamo, N (ELSEVIER, 2022-01-01)
    PURPOSE: Animal models are pivotal for elucidating pathophysiological mechanisms and evaluating novel therapies. This systematic review identified studies that developed or adapted animal models of limbal stem cell deficiency (LSCD), assessed their reporting quality, summarized their key characteristics, and established their clinical translational relevance to human disease. METHODS: The protocol was prospectively registered (PROSPERO CRD42020203937). Searches were conducted in PubMed, Ovid EMBASE and Web of Science in August 2020. Two authors screened citations, extracted data, assessed the reporting quality of eligible studies using the ARRIVE guidelines, and judged the clinical translational relevance of each model using a custom matrix. RESULTS: 105 studies were included. Rabbits were the most common animal species. Overall, 97% of studies recapitulated LSCD to a clinical etiology, however 62% did not provide sufficient methodological detail to enable independent reproduction of the model. Adverse events and/or exclusion of animals were infrequently (20%) reported. Approximately one-quarter of studies did not produce the intended severity of LSCD; 34% provided insufficient information to assess the fidelity of disease induction. Adjunctive diagnostic confirmation of LSCD induction was performed in 13% of studies. CONCLUSIONS: This is the first systematic review to assess the reporting quality and clinical translational relevance of animal models of LSCD. Models of LSCD have evolved over time, resulting in variable reporting of the characteristics of animals, experimental procedures and adverse events. In most studies, validation of LSCD was made using clinical tests; newer adjunctive techniques would enhance diagnostic validation. As most studies sought to evaluate novel therapies for LSCD, animal models should ideally recapitulate all features of the condition that develop in patients.
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    Targeted delivery of LM22A-4 by cubosomes protects retinal ganglion cells in an experimental glaucoma model
    Ding, Y ; Chow, SH ; Chen, J ; Le Brun, AP ; Wu, C-M ; Duff, AP ; Wang, Y ; Song, J ; Wang, J-H ; Wong, VHY ; Zhao, D ; Nishimura, T ; Lee, T-H ; Conn, CE ; Hsu, H-Y ; Bui, B ; Liu, G-S ; Shen, H-H (ELSEVIER SCI LTD, 2021-04-29)
    Glaucoma, a major cause of irreversible blindness worldwide, is associated with elevated intraocular pressure (IOP) and progressive loss of retinal ganglion cells (RGCs) that undergo apoptosis. A mechanism for RGCs injury involves impairment of neurotrophic support and exogenous supply of neurotrophic factors has been shown to be beneficial. However, neurotrophic factors can have widespread effects on neuronal tissues, thus targeting neurotrophic support to injured neurons may be a better neuroprotective strategy. In this study, we have encapsulated LM22A-4, a small neurotrophic factor mimetic, into Annexin V-conjugated cubosomes (L4-ACs) for targeted delivery to injured RGCs in a model of acute IOP elevation, which is induced by acute IOP elevation. We have tested cubosomes formulations that encapsulate from 9% to 33% LM22A-4. Our data indicated that cubosomes encapsulating 9% and 17% LM22A-4 exhibited a mixture of Pn3m/Im3m cubic phase, whereas 23% and 33% showed a pure Im3m cubic phase. We found that 17% L4-ACs with Pn3m/Im3m symmetries showed better in-situ and in-vitro lipid membrane interactions than the 23% and 33% L4-ACs with Im3m symmetry. In vivo experiments showed that 17% L4-ACs targeted the posterior retina and the optic nerve head, which prevented RGCs loss and improved functional outcomes in a mouse model of acute IOP elevation. These results provide evidence that Annexin V-conjugated cubosomes-based LM22A-4 delivery may be a useful targeted approach to prevent the progression of RGCs loss in glaucoma. STATEMENT OF SIGNIFICANCE: Recent studies suggest that the therapy of effectively delivering neurotrophic factors to the injured retinal ganglion cells (RGCs) could promote the survival of RGCs in glaucoma. Our present work has for the first time used cubosomes as an active targeted delivery system and have successfully delivered a neuroprotective drug to the damaged RGCs in vivo. Our new cubosomal formulation can protect apoptotic cell death in vitro and in vivo, showing that cubosomes are a promising drug carrier system for ocular drug delivery and glaucoma treatment. We have further found that by controlling cubosomes in Pn3m phase we can facilitate delivery of neuroprotective drug through apoptotic membranes. This data, we believe, has important implications for future design and formulation of cubosomes for therapeutic applications.
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    Do Additional Testing Locations Improve the Detection of Macular Perimetric Defects in Glaucoma?
    Montesano, G ; McKendrick, AM ; Turpin, A ; Brusini, P ; Oddone, F ; Fogagnolo, P ; Perdicchi, A ; Johnson, CA ; Lanzetta, P ; Rossetti, LM ; Garway-Heath, DF ; Crabb, DP (ELSEVIER SCIENCE INC, 2021-11-18)
    PURPOSE: To evaluate the ability of additional central testing locations to improve detection of macular visual field (VF) defects in glaucoma. DESIGN: Prospective cross-sectional study. PARTICIPANTS: Four hundred forty healthy people and 499 patients with glaucomatous optic neuropathy (GON) were tested with a fundus tracked perimeter (CMP; CenterVue) using a 24-2 grid with 12 additional macular locations (24-2+). METHODS: Glaucomatous optic neuropathy was identified based on expert evaluation of optic nerve head photographs and OCT scans, independently of the VF. We defined macular defects as locations with measurements outside the 5% and 2% normative limits on total deviation (TD) and pattern deviation (PD) maps within the VF central 10°. Classification was based on the total number of affected macular locations (overall detection) or the largest number of affected macular locations connected in a contiguous cluster (cluster detection). Criteria based on the number of locations and cluster size were used to obtain equivalent specificity between the 24-2 grid and the 24-2+ grids, calculated using false detections in the healthy cohort. Partial areas under the receiver operating characteristic curve (pAUCs) were also compared at specificities of 95% or more. MAIN OUTCOME MEASURES: Matched specificity comparison of the ability to detect glaucomatous macular defects between the 24-2 and 24-2+ grids. RESULTS: At matched specificity, cluster detection identified more macular defects with the 24-2+ grid compared with the 24-2 grid. For example, the mean increase in percentage of detection was 8% (95% confidence interval [CI], 5%-11%) and 10% (95% CI, 7%-13%) for 5% TD and PD maps, respectively, and 5% (95% CI, 2%-7%) and 6% (95% CI, 4%-8%) for the 2% TD and PD maps, respectively. Good agreement was found between the 2 grids. The improvement measured by pAUCs was also significant but generally small. The percentage of eyes with macular defects ranged from about 30% to 50%. Test time for the 24-2+ grid was longer (21% increase) for both cohorts. Between 74% and 98% of defects missed by the 24-2 grid had at least 1 location with sensitivity of < 20 dB. CONCLUSIONS: Visual field examinations with additional macular locations can improve the detection of macular defects in GON modestly without loss of specificity when appropriate criteria are selected.
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    The mental health and wellbeing survey of Australian optometrists
    Bentley, SA ; Black, A ; Khawaja, N ; Fylan, F ; Griffiths, AM ; Wood, JM (WILEY, 2021-04-20)
    PURPOSE: To investigate the prevalence of mental health conditions and burnout among practising optometrists in Australia. METHODS: A cross-sectional survey of registered practising Australian optometrists was undertaken over a three-week period from mid-November 2019. The survey comprised three well-established mental health scales (Kessler Psychological Distress Scale [K10], Depression Anxiety Stress Scales [DASS-21] and Maslach Burnout Inventory [MBI]) and an open-ended question inviting comments. RESULTS: Five hundred and five respondents completed the K10, representing 8.8% of registered optometrists in Australia; 466 completed all three scales. Prevalence of moderate to severe psychological distress (K10 ≥ 25) was 30.7% (95% CI 26.7%-34.7%), with similar findings for depression and anxiety (DASS-21). Prevalence of high burnout, as indicated by MBI-GS exhaustion was 56.1% (95% CI 51.7%-60.4%), cynicism 57.1% (95% CI 52.7%-61.5%) and professional efficacy 23.1% (95% CI 19.4%-26.8%). Optometrists aged ≤ 30 years were 3.5 times more likely to report moderate to severe psychological distress compared to optometrists aged >30 years (OR = 3.54, P < 0.001, 95% CI 2.38-5.25). The most frequently mentioned work-related issues concerned retail pressures, workload and career dissatisfaction. CONCLUSIONS: The rates of mental health conditions and burnout reported by practising Australian optometrists were high compared with the general population and other health professionals. Younger age and burnout were significant risk factors for psychological distress. Interventions are required to address these issues, particularly for younger optometrists, and could include workplace modifications and building resilience to improve personal mental wellbeing and ensure patient safety.
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    Somatovisceral Convergence in Sleep-Wake Cycle: Transmitting Different Types of Information via the Same Pathway
    Levichkina, E ; Pigareva, ML ; Limanskaya, A ; Pigarev, IN (Frontiers Media SA, 2022-03-02)
    Convergence of somatic and visceral inputs occurs at the levels of nervous system ranging from spinal cord to cerebral cortex. This anatomical organization gave explanation to a referred pain phenomenon. However, it also presents a problem: How does the brain know what information is coming for processing—somatic or visceral - if both are transferred by the same spinal cord fibers by means of the standard neuronal spikes? Recent studies provided evidence for cortical processing of interoceptive information largely occurring in sleep, when somatosensation is suppressed, and for the corresponding functional brain networks rearrangement. We suggest that convergent units of the spinal cord would be able to collectively provide mainly somatosensory information in wakefulness and mainly visceral in sleep, solving the puzzle of somatovisceral convergence. We recorded spiking activity from the spinal cord lemniscus pathway during multiple sleep-wake cycles in freely behaving rabbits. In wakefulness high increased spiking corresponded to movements. When animals stopped moving this activity ceased, the fibers remained silent during passive wakefulness. However, upon transition to sleep fibers began firing again. Analysis of spiking patterns of individual fibers revealed that in the majority of them spiking rates recovered in slow wave sleep. Thus, despite cessation of motion and a corresponding decrease of somatic component of the convergent signal, considerable ascending signaling occurs during sleep, that is likely to be visceral. We also recorded evoked responses of the lemniscus pathway to innocuous electrostimulation of the abdominal viscera, and uncovered the existence of two groups of responses depending upon the state of vigilance. Response from an individual fiber could be detected either during wakefulness or in sleep, but not in both states. Wakefulness-responsive group had lower spiking rates in wakefulness and almost stopped spiking in sleep. Sleep-responsive retained substantial spiking during sleep. These groups also differed in spike amplitudes, indicative of fiber diameter differences; however, both had somatic responses during wakefulness. We suggest a mechanism that utilizes differences in somatic and visceral activities to extract both types of information by varying transmission thresholds, and discuss the implications of this mechanism on functional networks under normal and pathological conditions.
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    Dynamic coupling of oscillatory neural activity and its roles in visual attention
    Esghaei, M ; Treue, S ; Vidyasagar, TR (ELSEVIER SCIENCE LONDON, 2022-04-01)
    Oscillatory neural activity is believed to have a central role in information processing in the mammalian brain. While early studies often focussed on the function of individual frequency bands, there is emerging appreciation for the role of simultaneous activity in many distinct frequency bands and the interactions between them in high-level cognitive functions. Here, we focus on the role of cross-frequency coupling (CFC) in visual attention. First, we propose a framework that reconciles previous contrasting findings, showing how CFC could have a functional role on both intra- and interareal scales. Second, we outline how CFC between distinct frequency bands could label different submodalities of sensory information. Overall, our scheme provides a novel perspective of how interfrequency interaction contributes to efficient and dynamic processing of information across the brain.
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    Interventions for the Management of Computer Vision Syndrome: A Systematic Review and Meta-analysis.
    Singh, S ; McGuinness, MB ; Anderson, AJ ; Downie, LE (Elsevier BV, 2022-05-18)
    TOPIC: To evaluate the efficacy and safety of interventions for treating eye strain related to computer use relative to placebo or no treatment. CLINICAL RELEVANCE: Computer use is pervasive and often associated with eye strain, referred to as computer vision syndrome (CVS). Currently, no clinical guidelines exist to help practitioners provide evidence-based advice about CVS treatments, many of which are marketed directly to patients. This systematic review and meta-analysis was designed to help inform best practice for eye care providers. METHODS: Eligible randomized controlled trials (RCTs) were identified in Ovid MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and trial registries, searched from inception through November 23, 2021. Eligible studies were appraised for risk of bias and were synthesized. The certainty of the body of evidence was judged using the Grading of Recommendations, Assessment, Development, and Evaluation system. Standardized mean differences (SMDs) were used when differently scaled measures were combined. RESULTS: Forty-five RCTs, involving 4497 participants, were included. Multifocal lenses did not improve visual fatigue scores compared with single-vision lenses (3 RCTs; SMD, 0.11; 95% confidence interval [CI], -0.14 to 0.37; P = 0.38). Visual fatigue symptoms were not reduced by blue-blocking spectacles (3 RCTs), with evidence judged of low certainty. Relative to placebo, oral berry extract supplementation did not improve visual fatigue (7 RCTs; SMD, -0.27; 95% CI, -0.70 to 0.16; P = 0.22) or dry eye symptoms (4 RCTs; SMD, -0.10; 95% CI, -0.54 to 0.33; P = 0.65). Likewise, berry extract supplementation had no significant effects on critical flicker-fusion frequency (CFF) or accommodative amplitude. Oral omega-3 supplementation for 45 days to 3 months improved dry eye symptoms (2 RCTs; mean difference [MD], -3.36; 95% CI, -3.63 to -3.10 on an 18 unit scale; P < 0.00001) relative to placebo. Oral carotenoid supplementation improved CFF (2 RCTs; MD, 1.55 Hz; 95% CI, 0.42 to 2.67 Hz; P = 0.007) relative to placebo, although the clinical significance of this finding is unclear. DISCUSSION: We did not identify high-certainty evidence supporting the use of any of the therapies analyzed. Low-certainty evidence suggested that oral omega-3 supplementation reduces dry eye symptoms in symptomatic computer users.