Optometry and Vision Sciences - Research Publications

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    Topical Decorin Reduces Corneal Inflammation and Imparts Neuroprotection in a Mouse Model of Benzalkonium Chloride-induced Corneal Neuropathy.
    Wu, M ; Downie, LE ; Hill, LJ ; Chinnery, HR (Association for Research in Vision and Ophthalmology (ARVO), 2023-02-01)
    PURPOSE: We evaluated the neuroprotective and immunomodulatory effects of topical decorin in a murine model of benzalkonium chloride (BAK)-induced corneal neuropathy. METHODS: Topical BAK (0.1%) was administered daily to both eyes of female C57BL/6J mice (n = 14) for 7 days. One group of mice received topical decorin (1.07 mg/mL) eye drops to one eye and saline (0.9%) to the contralateral eye; the other group received saline eye drops to both eyes. All eye drops were given three times daily over the experimental period. A control group (n = 8) received daily topical saline only, instead of BAK. Optical coherence tomography imaging was performed before (at day 0) and after (day 7) treatment to evaluate the central corneal thickness. Whole-mount immunofluorescence staining was performed to evaluate the density of corneal intraepithelial nerves and immune cells. RESULTS: BAK-exposed eyes showed corneal epithelial thinning, infiltration of inflammatory macrophages and neutrophils, and a lower density of intraepithelial nerves. No change to the corneal stromal thickness or dendritic cell density was observed. After BAK exposure, decorin-treated eyes had a lower density of macrophages and less neutrophil infiltration and a higher nerve density than the saline-treated group. Contralateral eyes from the decorin-treated animals showed fewer macrophages and neutrophils relative to saline-treated animals. A negative correlation was found between corneal nerve density and macrophage or neutrophil density. CONCLUSIONS: Topical decorin provides neuroprotective and anti-inflammatory effects in a chemical model of BAK-induced corneal neuropathy. The attenuation of corneal inflammation by decorin may contribute to decreasing corneal nerve degeneration induced by BAK.
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    Victorian evolution of inherited retinal diseases natural history registry (VENTURE study): Rationale, methodology and initial participant characteristics
    Britten-Jones, AC ; O'Hare, F ; Edwards, TL ; Ayton, LN (WILEY, 2022-06-12)
    BACKGROUND: Emerging treatments are being developed for inherited retinal diseases, requiring a clear understanding of natural progression and a database of potential participants for clinical trials. This article describes the rationale, study design and methodology of the Victorian Evolution of inherited retinal diseases NaTUral history REgistry (VENTURE), including data from the first 150 participants enrolled. METHODS: VENTURE collects retrospective and prospective data from people with inherited retinal diseases. Following registration, participants are asked to attend a baseline examination using a standardised protocol to confirm their inherited retinal disease diagnosis. Examination procedures include (i) retinal function, using visual acuity and perimetry; (ii) retinal structure, using multimodal imaging and (iii) patient-reported outcomes. Participants' molecular diagnoses are obtained from their clinical records or through targeted-panel genetic testing by an independent laboratory. Phenotype and genotype data are used to enrol participants into disease-specific longitudinal cohort sub-studies. RESULTS: From 7 July 2020 to 30 December 2021, VENTURE enrolled 150 registrants (138 families) and most (63%) have a rod-cone dystrophy phenotype. From 93 participants who have received a probable molecular diagnosis, the most common affected genes are RPGR (13% of all registrants), USH2A (10%), CYP4V2 (7%), ABCA4 (5%), and CHM (5%). Most participants have early to moderate vision impairment, with over half (55%) having visual acuities of better than 6/60 (20/200) at registration. CONCLUSIONS: The VENTURE study will complement existing patient registries and help drive inherited retinal disease research in Australia, facilitating access to research opportunities for individuals with inherited retinal diseases.
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    Point-of-care tools to support optometric care provision to people with age-related macular degeneration: A randomised, placebo-controlled trial
    Gocuk, SA ; McKendrick, AM ; Downie, LE (WILEY, 2022-03-14)
    PURPOSE: Age-related macular degeneration (AMD) is a leading cause of vision impairment. This randomised placebo-controlled trial investigated whether point-of-care tools can improve optometrists' AMD knowledge and/or care provision. METHODS: Australian optometrists (n = 31) completed a demographics survey and theoretical AMD case study multiple-choice questions (MCQs) to assess their confidence in AMD care provision and AMD knowledge. Participants were then randomly assigned to one of three point-of-care tools (online 'Classification of Age-related macular degeneration and Risk Assessment Tool' (CARAT), paper CARAT, or 'placebo') to use when providing care to their subsequent 5-10 AMD patients. Participants self-audited the compliance of their AMD care to best practice for these patients, and a similar number of consecutive patients seen prior to enrolment. Post-intervention, participants retook the AMD knowledge MCQs and confidence survey. RESULTS: A total of 29 participants completed the study. At the study endpoint, clinical confidence relative to baseline improved with the paper CARAT, relative to placebo, for knowledge of AMD risk factors, asking patients about these factors and referring for medical retinal sub-specialist care. There were no between-group differences for the change in AMD knowledge scores. Considering record documentation for patients with any AMD severity, there were no significant between-group differences for documenting patient risk factors, AMD severity, clinical examination techniques or management. In a sub-analysis, the change from baseline in compliance for documenting discussions about patient smoking behaviours for early AMD patients was higher with use of the online CARAT relative to placebo (p = 0.04). For patients with intermediate AMD, the change from baseline in documenting the risk of progression to late AMD was greater among practitioners who used the paper CARAT, relative to placebo (p = 0.04). CONCLUSIONS: This study demonstrates that point-of-care clinical tools can improve practitioner confidence and aspects of the documentation of AMD clinical care by optometrists as assessed by self-audit.
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    Orientation pinwheels in primary visual cortex of a highly visual marsupial
    Jung, YJ ; Almasi, A ; Sun, SH ; Yunzab, M ; Cloherty, SL ; Bauquier, SH ; Renfree, M ; Meffin, H ; Ibbotson, MR (AMER ASSOC ADVANCEMENT SCIENCE, 2022-09-30)
    Primary visual cortices in many mammalian species exhibit modular and periodic orientation preference maps arranged in pinwheel-like layouts. The role of inherited traits as opposed to environmental influences in determining this organization remains unclear. Here, we characterize the cortical organization of an Australian marsupial, revealing pinwheel organization resembling that of eutherian carnivores and primates but distinctly different from the simpler salt-and-pepper arrangement of eutherian rodents and rabbits. The divergence of marsupials from eutherians 160 million years ago and the later emergence of rodents and rabbits suggest that the salt-and-pepper structure is not the primitive ancestral form. Rather, the genetic code that enables complex pinwheel formation is likely widespread, perhaps extending back to the common therian ancestors of modern mammals.
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    Interobserver Agreement of Electrode to Retina Distance Measurements in a Second-Generation (44-Channel) Suprachoroidal Retinal Prosthesis.
    Abbott, CJ ; Baglin, EK ; Kolic, M ; McGuinness, MB ; Titchener, SA ; Young, KA ; Yeoh, J ; Luu, CD ; Ayton, LN ; Petoe, MA ; Allen, PJ (Association for Research in Vision and Ophthalmology (ARVO), 2022-09-01)
    PURPOSE: The electrode to retina (ER) distance is an important contributory factor to the safety and efficacy of a suprachoroidal retinal prosthesis. Measuring ER distance may be performed by different observers during multisite studies. The aim of this study was to assess the interobserver agreement in measuring ER distance. METHODS: Three independent, trained observers measured ER distance from the center of each suprachoroidal electrode to the inner retinal pigment epithelium in spectral-domain optical coherence tomography (SD-OCT) B-scans. A total of 121 ER distance measurements from 77 B-scans collected over 5 months from one subject implanted with a second-generation 44-channel suprachoroidal retinal prosthesis (NCT03406416) were made by each observer. RESULTS: ER distance ranged from 208 to 509 µm. Pearson's correlation coefficient (ρ) showed agreement of 0.99 (95% confidence interval [CI] = 0.98-0.99) in measuring ER for each pairwise comparison. The mean difference in ER distance between observers ranged from 2.4 to 6.4 µm with pairwise limits of agreement (95% CI) of ±20 µm (5.5% of mean). Intraclass correlation coefficient (ICC) showed agreement of 0.98 (95% CI = 0.97-0.99) between observers. CONCLUSIONS: There is high agreement in measuring ER distances for suprachoroidal retinal prostheses using our systematic approach between multiple, trained observers, supporting the use of a single observer for each image. TRANSLATIONAL RELEVANCE: High interobserver agreement outcomes indicate that multiple, trained observers can be used to take ER measurements across different images in suprachoroidal retinal prosthesis studies. This improves multisite study efficiency and gives confidence in interpreting results relating to the safety and efficacy of suprachoroidal retinal prostheses.
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    Expression of muscarinic receptor subtypes in tree shrew ocular tissues and their regulation during the development of myopia
    McBrien, NA ; Jobling, AI ; Truong, HT ; Cottriall, CL ; Gentle, A (MOLECULAR VISION, 2009-03-02)
    PURPOSE: Muscarinic receptors are known to regulate several important physiologic processes in the eye. Antagonists to these receptors such as atropine and pirenzepine are effective at stopping the excessive ocular growth that results in myopia. However, their site of action is unknown. This study details ocular muscarinic subtype expression within a well documented model of eye growth and investigates their expression during early stages of myopia induction. METHODS: Total RNA was isolated from tree shrew corneal, iris/ciliary body, retinal, choroidal, and scleral tissue samples and was reverse transcribed. Using tree shrew-specific primers to the five muscarinic acetylcholine receptor subtypes (CHRM1-CHRM5), products were amplified using polymerase chain reaction (PCR) and their identity confirmed using automated sequencing. The expression of the receptor proteins (M1-M5) were also explored in the retina, choroid, and sclera using immunohistochemistry. Myopia was induced in the tree shrew for one or five days using monocular deprivation of pattern vision, and the expression of the receptor subtypes was assessed in the retina, choroid, and sclera using real-time PCR. RESULTS: All five muscarinic receptor subtypes were expressed in the iris/ciliary body, retina, choroid, and sclera while gene products corresponding to CHRM1, CHRM3, CHRM4, and CHRM5 were present in the corneal samples. The gene expression data were confirmed by immunohistochemistry with the M1-M5 proteins detected in the retina, choroid, and sclera. After one or five days of myopia development, muscarinic receptor gene expression remained unaltered in the retinal, choroidal, and scleral tissue samples. CONCLUSIONS: This study provides a comprehensive profile of muscarinic receptor gene and protein expression in tree shrew ocular tissues with all receptor subtypes found in tissues implicated in the control of eye growth. Despite the efficacy of muscarinic antagonists at inhibiting myopia development, the genes of the muscarinic receptor subtypes are neither regulated early in myopia (before measurable axial elongation) nor after significant structural change.
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    Improving optometry student interpersonal skills through online patient, clinician and student evaluation and feedback
    Nguyen, BN ; Ng, J ; Piano, MEF ; Cochrane, AL ; Guest, D (TAYLOR & FRANCIS LTD, 2023-04-21)
    CLINICAL RELEVANCE: Interpersonal skills are crucial for successful clinician-patient interactions. To prepare future optometrists for clinical practice, pedagogical evaluation is important to support the implementation of new strategies for teaching and evaluating interpersonal skills. BACKGROUND: Optometry students largely develop their interpersonal skills through in-person patient interactions. Telehealth is increasing, yet strategies to develop the interpersonal skills of students for teleconsulting have not been explored. This study aimed to assess the feasibility, effectiveness and perceived usefulness of an online, multisource (patients, clinicians and students) evaluation and feedback program for developing interpersonal skills. METHODS: Via an online teleconferencing platform, optometry students (n = 40) interacted with a volunteer patient, observed by a teaching clinician. Patients and clinicians evaluated the interpersonal skills of the student in two ways: (1) qualitative written feedback, and (2) quantitative rating (Doctors' Interpersonal Skills Questionnaire). All students received written patient and clinician feedback after the session, but not their quantitative ratings. A subset of students (n = 19) completed two sessions, self-ratings, and were provided with their written feedback and an audiovisual recording from their first interaction before completing the second session. All participants were invited to complete an anonymous survey at program completion. RESULTS: Patient and clinician overall interpersonal skills ratings were positively correlated (Spearman's r = 0.35, p = 0.03) and showed moderate agreement (Lin's concordance coefficient = 0.34). Student self-ratings did not match patient ratings (r = 0.01, p = 0.98), whereas there was moderate agreement between clinician and student ratings (Lin's concordance coefficient = 0.30). Ratings improved at the second visit (p = 0.01). Patient ratings were higher than clinicians (p = 0.01) and students (p = 0.03). All participants agreed that the program was feasible, useful and effective at fostering good interpersonal skills. CONCLUSION: Multisource feedback about interpersonal skills contributes to improvement in student performance. Patients and clinicians can evaluate and provide useful feedback to optometry students about their interpersonal skills using online methods.
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    Enhanced effective diffusion in sub-wavelength, axon-scale microchannels using surface acoustic waves
    Peng, D ; Tong, W ; Collins, DJ ; Ibbotson, MR ; Prawer, S ; Stamp, MEM (AIP Publishing, 2023-03-01)
    Excitation using surface acoustic waves (SAW) has demonstrated efficacy in improving microscale particle/chemical transport due to its ability to generate microscale wavelengths. However, the effects of acoustic stimulation on transport processes along the length of sub-wavelength microchannels and their underlying mechanisms, essential for long-range transport, have not been examined in detail. In this work, we investigate diffusion along the length of subwavelength microchannels using experimental and simulation approaches, demonstrating enhanced transport under SAW excitation. The microchannel-based enhanced diffusion mechanisms are further studied by investigating the acoustic pressure and streaming fields, finding that the degree of enhancement is a function of applied power, microchannel dimensions, and viscosity. This microchannel-based diffusion enhancement approach is applicable to microfluidic and biomedical microscale transport enhancement, with the findings here being relevant to acoustic-based micro-mixing and neurodegenerative therapies.
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    Integrating interprofessional electronic medical record teaching in preregistration healthcare degrees: A case study
    Lokmic-Tomkins, Z ; Gray, K ; Cheshire, L ; Parolini, A ; Sharp, M ; Tarrant, B ; Hill, N ; Rose, D ; Webster, M ; Virtue, D ; Brignell, A ; Waring, R ; Broussard, F ; Tsirgialos, A ; Cham, KM (ELSEVIER IRELAND LTD, 2023-01-01)
    BACKGROUND: Electronic medical record (EMR) adoption across healthcare necessitates a purposeful curriculum design to prepare graduates for the delivery of safe and effective patient care in digitally-enabled environments. OBJECTIVE: To describe the design and development of an Interprofessional Electronic Medical Record (iEMR) subject that introduces healthcare students to its utility in clinical settings. METHODS: A six-stage design-based educational research framework (Focus, Formulation, Contextualisation, Definition, Implementation, Evaluation) was used to instigate the iEMR design and development in nursing and five allied health graduate entry to practice (preregistration) degrees at an Australian university. RESULTS: In the Focus process, the concept and interdisciplinary partnerships were developed. The Formulation process secured grant support for subject design and development, including a rapid literature review to accommodate various course and curriculum structures. Discipline-specific subject themes were created through the Contextualisation process. During the Definition process, learning objectives and content resources were built. The Implementation process describes the pilot implementation in the nursing program, where assessment tasks were refined, and interdisciplinary clinical case studies originated. DISCUSSION: The design and development of an iEMR subject is underpinned by internal support for educational innovation and in alignment with digital health strategies in employer organisations. Identified barriers include faculty-level changes in strategic support for teaching innovation, managerial expectations of workload, the scope of work required by academics and learning designers, and the gap between the technology platform required to support online learning and the infrastructure needed to support simulated EMR use. A key discovery was the difficulty of finding EMR software, whether designed for teaching purposes or for clinical use, that could be adapted to meet the needs of this project. CONCLUSION: The lessons learned are relevant to educators and learning designers attempting a similar process. Issues remain surrounding the sustainability of the iEMR subject and maintaining academic responsibility for ongoing curriculum management.
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    Optimising visual attention in children with autism spectrum disorder: a comparison of fixation distributions viewing singing and speech
    Abel, LA ; Thompson, GA (Association for Research in Vision and Ophthalmology, 2017-06-01)
    Purpose : Many children with autism spectrum disorder (ASD) are at risk of social isolation and limited social development due to difficulties with gaze and visual attention to people. Studies have shown that children with ASD may prefer music to other stimuli. We hypothesised that a short video of a singer would elicit more attention to the performer, particularly to her face, than a video of her reading a story and that the child’s familiarity with the song and story would enhance attention. Methods : 16 children aged 7-10 (14 M, 2 F) with ASD took part. Stimuli were 4 videos 1 minute long. Content was a favourite song or story of the child, along with a song and story which were the same for all children. The performer, her clothing, lighting and sound level were the same across tasks. Props were a pair of drums for the songs and a storybook of similar size for the stories. Eye movements were recorded with an Eyelink 1000; areas of interest (AOIs) were defined for the face, prop and body. 3-way repeated measures ANOVAs were used to examine the proportion of total dwell time, the proportion of total fixations and pupil area for each AOI in each trial. Results : For dwell time proportion, a significant interaction was found for familiarity*AOI (F=7.45, p=.004), with gaze time to the face being increased for familiar trials (Table 1). Similarly, medium*AOI was significant (F=6.01, p=.013), with increased gaze time to the face and body and decreased time to the prop for the songs (Table 2). The same patterns were seen for proportion of fixation counts to the AOIs (familiarity*AOI F=4.97, p =.016; medium*AOI F=10.33, p=.001). For the pupil, only familiarity and AOI were significant; pupils were larger for familiar stimuli (F=16.70, p=.001) and for the face and prop (F=6.8, p=.015), with the body eliciting less dilation. Conclusions : As hypothesised, the videos of singing attracted children's gaze to the performer more than did those of her reading a story. Familiarity with the material being performed also attracted more attention to her face. Familiarity and gaze to the face also increased arousal, as indexed by pupil dilation. Observation by children with ASD of a singer, particularly one performing their favourite songs, may be a useful intervention for improving their social engagement skills.