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Ricci FS, Boldini A, Ma X, Beheshti M, Geruschat DR, Seiple WH, Rizzo JR, Porfiri M. Virtual reality as a means to explore assistive technologies for the visually impaired. PLOS DIGITAL HEALTH 2023; 2:e0000275. [PMID: 37339135 PMCID: PMC10281573 DOI: 10.1371/journal.pdig.0000275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 05/15/2023] [Indexed: 06/22/2023]
Abstract
Visual impairment represents a significant health and economic burden affecting 596 million globally. The incidence of visual impairment is expected to double by 2050 as our population ages. Independent navigation is challenging for persons with visual impairment, as they often rely on non-visual sensory signals to find the optimal route. In this context, electronic travel aids are promising solutions that can be used for obstacle detection and/or route guidance. However, electronic travel aids have limitations such as low uptake and limited training that restrict their widespread use. Here, we present a virtual reality platform for testing, refining, and training with electronic travel aids. We demonstrate the viability on an electronic travel aid developed in-house, consist of a wearable haptic feedback device. We designed an experiment in which participants donned the electronic travel aid and performed a virtual task while experiencing a simulation of three different visual impairments: age-related macular degeneration, diabetic retinopathy, and glaucoma. Our experiments indicate that our electronic travel aid significantly improves the completion time for all the three visual impairments and reduces the number of collisions for diabetic retinopathy and glaucoma. Overall, the combination of virtual reality and electronic travel aid may have a beneficial role on mobility rehabilitation of persons with visual impairment, by allowing early-phase testing of electronic travel aid prototypes in safe, realistic, and controllable settings.
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Affiliation(s)
- Fabiana Sofia Ricci
- Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Center for Urban Science and Progress, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
| | - Alain Boldini
- Center for Urban Science and Progress, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Department of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
| | - Xinda Ma
- Department of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
| | - Mahya Beheshti
- Department of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Department of Rehabilitation Medicine, New York University Langone Health, New York, NY, United States of America
| | - Duane R. Geruschat
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - William H. Seiple
- Lighthouse Guild, New York, NY, United States of America
- Department of Ophthalmology, New York University Grossman School of Medicine, New York, NY, United States of America
| | - John-Ross Rizzo
- Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Department of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Department of Rehabilitation Medicine, New York University Langone Health, New York, NY, United States of America
- Department of Neurology, New York University Langone Health, New York, NY, United States of America
| | - Maurizio Porfiri
- Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Center for Urban Science and Progress, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
- Department of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, Brooklyn, NY, United States of America
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2
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Petoe MA, Titchener SA, Kolic M, Kentler WG, Abbott CJ, Nayagam DAX, Baglin EK, Kvansakul J, Barnes N, Walker JG, Epp SB, Young KA, Ayton LN, Luu CD, Allen PJ. A Second-Generation (44-Channel) Suprachoroidal Retinal Prosthesis: Interim Clinical Trial Results. Transl Vis Sci Technol 2021; 10:12. [PMID: 34581770 PMCID: PMC8479573 DOI: 10.1167/tvst.10.10.12] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To report the initial safety and efficacy results of a second-generation (44-channel) suprachoroidal retinal prosthesis at 56 weeks after device activation. Methods Four subjects, with advanced retinitis pigmentosa and bare-light perception only, enrolled in a phase II trial (NCT03406416). A 44-channel electrode array was implanted in a suprachoroidal pocket. Device stability, efficacy, and adverse events were investigated at 12-week intervals. Results All four subjects were implanted successfully and there were no device-related serious adverse events. Color fundus photography indicated a mild postoperative subretinal hemorrhage in two recipients, which cleared spontaneously within 2 weeks. Optical coherence tomography confirmed device stability and position under the macula. Screen-based localization accuracy was significantly better for all subjects with device on versus device off. Two subjects were significantly better with the device on in a motion discrimination task at 7, 15, and 30°/s and in a spatial discrimination task at 0.033 cycles per degree. All subjects were more accurate with the device on than device off at walking toward a target on a modified door task, localizing and touching tabletop objects, and detecting obstacles in an obstacle avoidance task. A positive effect of the implant on subjects' daily lives was confirmed by an orientation and mobility assessor and subject self-report. Conclusions These interim study data demonstrate that the suprachoroidal prosthesis is safe and provides significant improvements in functional vision, activities of daily living, and observer-rated quality of life. Translational Relevance A suprachoroidal prosthesis can provide clinically useful artificial vision while maintaining a safe surgical profile.
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Affiliation(s)
- Matthew A Petoe
- Bionics Institute, East Melbourne, Victoria, Australia.,Medical Bionics Department, University of Melbourne, Melbourne, Victoria, Australia
| | - Samuel A Titchener
- Bionics Institute, East Melbourne, Victoria, Australia.,Medical Bionics Department, University of Melbourne, Melbourne, Victoria, Australia
| | - Maria Kolic
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - William G Kentler
- Department of Biomedical Engineering, University of Melbourne, Melbourne, Victoria, Australia
| | - Carla J Abbott
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - David A X Nayagam
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Pathology, University of Melbourne, St. Vincent's Hospital, Victoria, Australia
| | - Elizabeth K Baglin
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Jessica Kvansakul
- Bionics Institute, East Melbourne, Victoria, Australia.,Medical Bionics Department, University of Melbourne, Melbourne, Victoria, Australia
| | - Nick Barnes
- Research School of Engineering, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Janine G Walker
- Research School of Engineering, Australian National University, Canberra, Australian Capital Territory, Australia.,Health & Biosecurity, CSIRO, Canberra, Australian Capital Territory, Australia
| | | | - Kiera A Young
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Lauren N Ayton
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia.,Department of Optometry and Vision Sciences, University of Melbourne, Australia
| | - Chi D Luu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Penelope J Allen
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
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Quantitative assessment of visual pathway function in blind retinitis pigmentosa patients. Clin Neurophysiol 2021; 132:392-403. [PMID: 33450562 DOI: 10.1016/j.clinph.2020.11.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 11/02/2020] [Accepted: 11/08/2020] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The current methods used to assess visual function in blind retinitis pigmentosa (RP) patients are mostly subjective. We aimed to identify effective, objective methods. METHODS We enrolled patients diagnosed with blindness associated with RP; we finally selected 26 patients (51 eyes) with a visual field radius less than 10 degrees and divided them into the following 4 groups by best-corrected visual acuity (BCVA): group 1, no light perception (NLP, 4 eyes); group 2, light perception (LP, 12 eyes); group 3, hand movement or finger counting (faint form perception, FFP, 22 eyes); and group 4, BCVA from 0.1 to 0.8 (form perception, FP, 13 eyes). All patients underwent optometry, optical coherence tomography (OCT), color fundus photography, fundus autofluorescence (FAF), full field electroretinography (ffERG), pattern electroretinography (PERG), multifocal electroretinography (mf-ERG), pattern visual evoked potential (PVEP), flash visual evoked potential (FVEP), and pupillary light response (PLR) assessments. Five patients in groups 1, 2, and 3 (1, 2, and 2 subjects, respectively) underwent functional magnetic resonance imaging (fMRI) scans and were compared with five healthy subjects. RESULTS The outer plexiform layer was thinner in group 1, and the outer nuclear layer was thinner in groups 1 and 2. The ffERG, PERG, and mf-ERG findings were unrecordable in all four groups. The P2 amplitude of the FVEP was significantly lower in groups 1 and 2, while the P100 amplitude of the PVEP was higher in groups 2, 3 and 4 than in group 1. After white- and blue-light stimuli, the PLR thresholds in the patients without form perception were significantly higher. The threshold of the PLR stimulated by blue and white light was negatively correlated with the amplitudes of P2 and P100. Moreover, the fMRI findings showed that some RP patients have significant visual cortex activation in response to certain types of stimulation. However, statistical analysis was not performed because of the small number of cases. CONCLUSIONS OCT, VEP, PLR and fMRI assessments can evaluate residual visual pathway function in blind RP patients. SIGNIFICANCE Our study may have clinical significance for the potential prediction of RP patient prognoses and the effects after clinical trials.
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Benson MD, MacDonald IM, Sheehan M, Jain S. Improved electroretinographic responses following dietary intervention in a patient with Refsum disease. JIMD Rep 2020; 55:32-37. [PMID: 32904930 PMCID: PMC7463047 DOI: 10.1002/jmd2.12147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 06/09/2020] [Accepted: 06/17/2020] [Indexed: 01/08/2023] Open
Abstract
Refsum disease is a rare inherited metabolic disorder arising from a defect in peroxisomal metabolism. Patients lack the functional enzyme phytanoyl-CoA hydroxylase, resulting in perturbed alpha oxidation of fatty acids. Phytanic acid accumulates in nervous and adipose tissue and leads to several disease phenotypes including early-onset retinal degeneration, hearing loss, peripheral neuropathy, anosmia, and cerebellar ataxia, among others. Currently, restricting dietary phytanic acid is the only means of altering the chronic sequelae and the disease course. While dietary intervention has been demonstrated to improve peripheral neuropathy, ichthyosis, and ataxia, there have been no reports of improved retinal function in patients with Refsum disease. We describe the case of a 51-year-old patient with molecularly and biochemically confirmed Refsum disease who underwent electroretinography before and after beginning a phytanic acid-restricted diet. His post-intervention 30 Hz flicker electroretinogram demonstrated significantly improved waveform amplitudes and implicit times, suggesting improved retinal function. Thus, we propose that the possibility exists for some visual recovery in these patients and we highlight the utility of performing standardized electroretinography to assess treatment response in Refsum disease.
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Affiliation(s)
- Matthew D. Benson
- Department of Ophthalmology and Visual SciencesUniversity of AlbertaEdmontonAlbertaCanada
| | - Ian M. MacDonald
- Department of Ophthalmology and Visual SciencesUniversity of AlbertaEdmontonAlbertaCanada
| | - Melissa Sheehan
- Nutrition Services, Alberta Health ServicesStollery Children's HospitalEdmontonAlbertaCanada
| | - Shailly Jain
- Department of Medical GeneticsUniversity of AlbertaEdmontonAlbertaCanada
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Kole C, Klipfel L, Yang Y, Ferracane V, Blond F, Reichman S, Millet-Puel G, Clérin E, Aït-Ali N, Pagan D, Camara H, Delyfer MN, Nandrot EF, Sahel JA, Goureau O, Léveillard T. Otx2-Genetically Modified Retinal Pigment Epithelial Cells Rescue Photoreceptors after Transplantation. Mol Ther 2017; 26:219-237. [PMID: 28988713 PMCID: PMC5762984 DOI: 10.1016/j.ymthe.2017.09.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 08/17/2017] [Accepted: 09/03/2017] [Indexed: 12/13/2022] Open
Abstract
Inherited retinal degenerations are blinding diseases characterized by the loss of photoreceptors. Their extreme genetic heterogeneity complicates treatment by gene therapy. This has motivated broader strategies for transplantation of healthy retinal pigmented epithelium to protect photoreceptors independently of the gene causing the disease. The limited clinical benefit for visual function reported up to now is mainly due to dedifferentiation of the transplanted cells that undergo an epithelial-mesenchymal transition. We have studied this mechanism in vitro and revealed the role of the homeogene OTX2 in preventing dedifferentiation through the regulation of target genes. We have overexpressed OTX2 in retinal pigmented epithelial cells before their transplantation in the eye of a model of retinitis pigmentosa carrying a mutation in Mertk, a gene specifically expressed by retinal pigmented epithelial cells. OTX2 increases significantly the protection of photoreceptors as seen by histological and functional analyses. We observed that the beneficial effect of OTX2 is non-cell autonomous, and it is at least partly mediated by unidentified trophic factors. Transplantation of OTX2-genetically modified cells may be medically effective for other retinal diseases involving the retinal pigmented epithelium as age-related macular degeneration.
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Affiliation(s)
- Christo Kole
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Laurence Klipfel
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Ying Yang
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Vanessa Ferracane
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Frederic Blond
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Sacha Reichman
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Géraldine Millet-Puel
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Emmanuelle Clérin
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Najate Aït-Ali
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Delphine Pagan
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Hawa Camara
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Marie-Noëlle Delyfer
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France; Unité Rétine, Uvéite et Neuro-Ophtalmologie, Département d'Ophtalmologie, Centre Hospitalier Universitaire de Bordeaux, Bordeaux, France
| | - Emeline F Nandrot
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Jose-Alain Sahel
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Olivier Goureau
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France
| | - Thierry Léveillard
- INSERM, U968, Paris 75012, France; Sorbonne Universités, UPMC Univ Paris 06 UMR_S 968, Institut de la Vision, Paris 75012, France; CNRS, UMR_7210, Paris 75012, France.
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Abstract
PURPOSE This study aimed to determine the feasibility of an assessment of vision-related orientation and mobility (O&M) tasks in persons with severe vision loss. These tasks may be used for future low vision rehabilitation clinical assessments or as outcome measures in vision restoration trials. METHODS Forty legally blind persons (mean visual acuity logMAR 2.3, or hand movements) with advanced retinitis pigmentosa participated in the Orientation & Mobility-Very Low Vision (O&M-VLV) subtests from the Low Vision Assessment of Daily Activities (LoVADA) protocol. Four categories of tasks were evaluated: route travel in three indoor hospital environments, a room orientation task (the "cafe"), a visual exploration task (the "gallery"), and a modified version of the Timed Up and Go (TUG) test, which assesses re-orientation and route travel. Spatial cognition was assessed using the Stuart Tactile Maps test. Visual acuity and visual fields were measured. RESULTS A generalized linear regression model showed that a number of measures in the O&M-VLV tasks were related to residual visual function. The percentage of preferred walking speed without an aid on three travel routes was associated with visual field (p < 0.01 for all routes) whereas the number of contacts with obstacles during route travel was associated with acuity (p = 0.001). TUG-LV task time was associated with acuity (p = 0.003), as was the cafe time and distance traveled (p = 0.006 and p < 0.001, respectively). The gallery score was the only measure that was significantly associated with both residual acuity and fields (p < 0.001 and p = 0.001, respectively). CONCLUSIONS The O&M-VLV was designed to capture key elements of O&M performance in persons with severe vision loss, which is a population not often studied previously. Performance on these tasks was associated with both binocular visual acuity and visual field. This new protocol includes assessments of orientation, which may be of benefit in vision restoration clinical trials.
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Abstract
PURPOSE The Independent Mobility Questionnaire (IMQ) assesses participants' perceived ability for independent mobility. However, it has not been validated in a severely visually impaired population. The aim of this study was to explore the IMQ's psychometric properties in participants with severe visual impairment. METHODS This was a cross-sectional study of 40 participants with retinitis pigmentosa (better eye visual acuity <20/200 and/or visual field <10%). The key psychometric properties of the IMQ were examined using Rasch analysis, including precision, targeting, and item fit. Construct validity was assessed by testing the correlation between the IMQ and the Mobility and Independence subscale of the Impact of Vision Impairment questionnaire (Pearson correlation coefficient, r). Criterion validity was also assessed. RESULTS The IMQ had excellent precision (Person Separation Index, 3.01) with the capacity to distinguish at least four strata of participant ability, and item difficulty was well targeted to participant ability (difference between mean person and item measures, -0.21). Items 34, 35, 21, and 14 displayed misfit (infit MnSq >1.4); however, given our sample size restrictions, these items were not removed from the analysis. The IMQ had good construct validity (moderate correlation with the Impact of Vision Impairment Mobility subscale, r = 0.595, p < 0.05) but did not demonstrate criterion validity. CONCLUSIONS The psychometric properties of the IMQ were promising. Our findings are useful for researchers evaluating the effectiveness of novel treatment technologies on mobility in a severely visually impaired population from the participant's perspective. However, further validation studies in larger samples are required to confirm our results.
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8
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Barnes N, Scott AF, Lieby P, Petoe MA, McCarthy C, Stacey A, Ayton LN, Sinclair NC, Shivdasani MN, Lovell NH, McDermott HJ, Walker JG. Vision function testing for a suprachoroidal retinal prosthesis: effects of image filtering. J Neural Eng 2016; 13:036013. [DOI: 10.1088/1741-2560/13/3/036013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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9
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Eysteinsson T, Hardarson SH, Olafsdottir OB, Stefánsson E. Is metabolic imaging a new tool to monitor progression in retinal degenerations and atrophy? Acta Ophthalmol 2015; 93:e437-8. [PMID: 26387502 DOI: 10.1111/aos.12773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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10
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Fox DA. Retinal and visual system: occupational and environmental toxicology. HANDBOOK OF CLINICAL NEUROLOGY 2015; 131:325-40. [PMID: 26563796 DOI: 10.1016/b978-0-444-62627-1.00017-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Occupational chemical exposure often results in sensory systems alterations that occur without other clinical signs or symptoms. Approximately 3000 chemicals are toxic to the retina and central visual system. Their dysfunction can have immediate, long-term, and delayed effects on mental health, physical health, and performance and lead to increased occupational injuries. The aims of this chapter are fourfold. First, provide references on retinal/visual system structure, function, and assessment techniques. Second, discuss the retinal features that make it especially vulnerable to toxic chemicals. Third, review the clinical and corresponding experimental data regarding retinal/visual system deficits produced by occupational toxicants: organic solvents (carbon disulfide, trichloroethylene, tetrachloroethylene, styrene, toluene, and mixtures) and metals (inorganic lead, methyl mercury, and mercury vapor). Fourth, discuss occupational and environmental toxicants as risk factors for late-onset retinal diseases and degeneration. Overall, the toxicants altered color vision, rod- and/or cone-mediated electroretinograms, visual fields, spatial contrast sensitivity, and/or retinal thickness. The findings elucidate the importance of conducting multimodal noninvasive clinical, electrophysiologic, imaging and vision testing to monitor toxicant-exposed workers for possible retinal/visual system alterations. Finally, since the retina is a window into the brain, an increased awareness and understanding of retinal/visual system dysfunction should provide additional insight into acquired neurodegenerative disorders.
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Affiliation(s)
- Donald A Fox
- Departments of Vision Sciences, Biology and Biochemistry, Pharmacology, and Health and Human Performance, University of Houston, Houston, TX, USA.
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11
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Ayton LN, Blamey PJ, Guymer RH, Luu CD, Nayagam DAX, Sinclair NC, Shivdasani MN, Yeoh J, McCombe MF, Briggs RJ, Opie NL, Villalobos J, Dimitrov PN, Varsamidis M, Petoe MA, McCarthy CD, Walker JG, Barnes N, Burkitt AN, Williams CE, Shepherd RK, Allen PJ. First-in-human trial of a novel suprachoroidal retinal prosthesis. PLoS One 2014; 9:e115239. [PMID: 25521292 PMCID: PMC4270734 DOI: 10.1371/journal.pone.0115239] [Citation(s) in RCA: 199] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 11/18/2014] [Indexed: 11/19/2022] Open
Abstract
Retinal visual prostheses (“bionic eyes”) have the potential to restore vision to blind or profoundly vision-impaired patients. The medical bionic technology used to design, manufacture and implant such prostheses is still in its relative infancy, with various technologies and surgical approaches being evaluated. We hypothesised that a suprachoroidal implant location (between the sclera and choroid of the eye) would provide significant surgical and safety benefits for patients, allowing them to maintain preoperative residual vision as well as gaining prosthetic vision input from the device. This report details the first-in-human Phase 1 trial to investigate the use of retinal implants in the suprachoroidal space in three human subjects with end-stage retinitis pigmentosa. The success of the suprachoroidal surgical approach and its associated safety benefits, coupled with twelve-month post-operative efficacy data, holds promise for the field of vision restoration. Trial Registration Clinicaltrials.gov NCT01603576
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Affiliation(s)
- Lauren N. Ayton
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- * E-mail:
| | - Peter J. Blamey
- Bionics Institute, East Melbourne, Australia
- Department of Medical Bionics, University of Melbourne, East Melbourne, Australia
| | - Robyn H. Guymer
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Chi D. Luu
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - David A. X. Nayagam
- Bionics Institute, East Melbourne, Australia
- Department of Pathology, University of Melbourne, St Vincent's Hospital Melbourne, Fitzroy, Australia
| | | | - Mohit N. Shivdasani
- Bionics Institute, East Melbourne, Australia
- Department of Medical Bionics, University of Melbourne, East Melbourne, Australia
| | - Jonathan Yeoh
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Mark F. McCombe
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Robert J. Briggs
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Nicholas L. Opie
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | | | - Peter N. Dimitrov
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Mary Varsamidis
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | | | - Chris D. McCarthy
- NICTA, Computer Vision Research Group, Canberra, Australia
- National Institute for Mental Health Research, Australian National University, Canberra, Australia
| | - Janine G. Walker
- NICTA, Computer Vision Research Group, Canberra, Australia
- National Institute for Mental Health Research, Australian National University, Canberra, Australia
| | - Nick Barnes
- NICTA, Computer Vision Research Group, Canberra, Australia
- National Institute for Mental Health Research, Australian National University, Canberra, Australia
| | - Anthony N. Burkitt
- Bionics Institute, East Melbourne, Australia
- Centre for Neural Engineering, University of Melbourne, National Information and Communications Technology Australia (NICTA), Ltd., Melbourne, Australia
| | | | - Robert K. Shepherd
- Bionics Institute, East Melbourne, Australia
- Department of Medical Bionics, University of Melbourne, East Melbourne, Australia
| | - Penelope J. Allen
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
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