This paper describes the interface and testing of an indoor navigation app - ASSIST - that guides blind & visually impaired (BVI) individuals through an indoor environment with high accuracy while ...augmenting their understanding of the surrounding environment. ASSIST features personalized interfaces by considering the unique experiences that BVI individuals have in indoor wayfinding and offers multiple levels of multimodal feedback. After an overview of the technical approach and implementation of the first prototype of the ASSIST system, the results of two pilot studies performed with BVI individuals are presented - a performance study to collect data on mobility (walking speed, collisions, and navigation errors) while using the app, and a usability study to collect user evaluation data on the perceived helpfulness, safety, ease-of-use, and overall experience while using the app. Our studies show that ASSIST is useful in providing users with navigational guidance, improving their efficiency and (more significantly) their safety and accuracy in wayfinding indoors. Findings and user feedback from the studies confirm some of the previous results, while also providing some new insights into the creation of such an app, including the use of customized user interfaces and expanding the types of information provided.
To investigate a relationship between the inner segment-outer segment (IS-OS) junctional layer integrity and the overlying retinal sensitivity assessed by Spectral OCT/SLO (spectral-domain optical ...coherence tomography) and microperimetry testing in patients with dry and wet forms of age-related macular degeneration (AMD).
Spectral-domain optical coherence tomography examination and microperimetry testing were performed in 55 eyes of 43 consecutive patients with AMD. Microperimetry maps were registered onto three-dimensional retinal topography maps, and point-to-point analysis of correlation between microperimetric retinal sensitivities and corresponding status of the underlying IS-OS junctional layer was performed. In addition, the analysis of correlation between the best-corrected visual acuity and the integrity of IS-OS layer in the center of the fovea also was performed.
Retinal sensitivity was inversely and strongly correlated with the integrity of IS-OS layer in both dry and wet forms of AMD (correlation coefficient r = -0.75 95% confidence interval, 0.49-0.88, P < 0.001, and -0.79 95% confidence interval, 0.61-0.89, P < 0.001, respectively). The correlation between the best-corrected visual acuity and the integrity of IS-OS layer in the center of fovea was less significant (r = -0.58 95% confidence interval, 0.19-0.79, P = 0.02, for dry AMD, and r = -0.6 95% confidence interval, 0.32-0.78, P = 0.015, for wet AMD).
Retinal sensitivity consistently correlated with the status of underlying IS-OS junctional layer in both dry and wet forms of AMD. Loss of IS-OS layer is significantly associated with poor retinal sensitivity, assessed by microperimetry. Compared with visual acuity, functional testing with microperimetry appears to more consistently correlate with changes in the outer retina, such as IS-OS junctional integrity, especially, in patients with wet AMD.
Adherence to medication treatment protocols and active participation by individuals in their medical care are important for all patients, but especially for those with chronic conditions such as ...vision loss. Adherence is crucial for decreasing avoidable vision loss. Failure to take medications as prescribed and keep scheduled appointments reduces treatment effectiveness, increases complications and results in poorer outcomes. Reasons for nonadherence vary by diagnosis and include not understanding the importance of adherence, low health literacy, lack of adequate self-efficacy, low level of activation and behavioral issues including depression. Patients may lack information about their condition and its prognosis, available treatment alternatives, and other essential information such as how to monitor their eye condition, what to do if vision deteriorates and how to get needed community-based help. Each of these factors impedes patients' ability to engage with their physician and participate in their own care. The ability of individuals with vision loss to actively and effectively manage their health care, ie, activation, has been understudied. When patients are involved with their own care, their care experience, and most importantly, their outcomes, are improved. Identifying antecedents of adherence may help provide disease- and patient-specific pathways to reduce avoidable vision loss. Keywords: avoidable vision loss, adherence, activation, engagement, patient activation, patient engagement, AMD, diabetic eye disease, glaucoma
Based on statistics from the WHO and the International Agency for the Prevention of Blindness, an estimated 43.3 million people have blindness and 295 million have moderate and severe vision ...impairment globally as of 2020, statistics expected to increase to 61 million and 474 million respectively by 2050, staggering numbers. Blindness and low vision (BLV) stultify many activities of daily living, as sight is beneficial to most functional tasks. Assistive technologies for persons with blindness and low vision (pBLV) consist of a wide range of aids that work in some way to enhance one's functioning and support independence. Although handheld and head-mounted approaches have been primary foci when building new platforms or devices to support function and mobility, this perspective reviews potential shortcomings of these form factors or embodiments and posits that a body-centered approach may overcome many of these limitations.
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.
To investigate the combination of 3D optical coherence tomography (OCT) retinal thickness measurements and superimposed scanning laser ophthalmoscopy (SLO) microperimetry obtained using a Spectral ...OCT/SLO and to test the correlation between retinal thickness and retinal sensitivity in retinal diseases grouped according to anatomic locations.
Patients with various retinal diseases and subjects with normal fundi underwent microperimetry testing and imaging with the Spectral OCT/SLO. Based on the Spectral OCT/SLO findings, the participants were divided into 4 groups: patients with retinal thickening due to the outer retina pathology (group I); patients with retinal thickening due to the cystic changes observed in the inner retina (group II); patients with macular neurosensory retina thinning associated with geographic atrophy or underlying subretinal cicatricial changes (group III), and subjects with unremarkable fundus appearance and normal appearing retina on Spectral OCT/SLO (group IV). The primary outcome was the correlation coefficient (r) between Spectral OCT/SLO-measured macular thickness and microperimetry values.
Correlations between retinal thickness and psychophysical thresholds were calculated for each patient, and these values were averaged within groups. The mean correlation values (Pearson product movement) were as follows: for group I (n = 21 eyes) r = 0.04; for group II (n = 24 eyes) r = -0.53; for group III (n = 16 eyes) r = 0.41, and for group IV (n = 15 eyes) r = 0.04.
The combination of 3D OCT images and superimposed SLO microperimetry obtained by Spectral OCT/SLO demonstrated that thickening due to cystic changes of the inner retinal layers or thinning of the neurosensory retina on OCT correlated most significantly with decreases in psychophysical threshold sensitivities.
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.
This paper investigates the tools and practices used by Orientation and Mobility (O&M) specialists in instructing people who are blind or have low vision in concepts, skills, and techniques for safe ...and independent travel. Based on interviews with experienced instructors who practice in different O&M settings we find that a shortage of qualified specialists and restrictions on in-person activities during COVID-19 has accelerated interest in remote instruction and assessment, while widespread adoption of smartphones with accessibility support has driven interest in assistive apps. This presents both opportunities and challenges for a practice that is traditionally conducted in-person and assessed through qualitative observations. In response we identify multiple opportunities for HCI research in service of O&M, including: supporting a 'physician's assistant' model of remote O&M instruction and assessment, matching O&M instructors' clients with guide dogs, highlighting clients' progress towards O&M goals, and collaboratively planning routes and monitoring clients' independent travel progress.
Purpose: To determine whether retinal dysfunction in obligate carriers of the Bardet-Biedl syndrome (BBS) could be observed in local electroretinographic responses obtained with the multifocal ...electroretinogram (mfERG). Methods: Six obligate carriers of the BBS were examined for the study. Examination of each carrier included an ocular examination and mfERG testing of one eye. For the mfERG, we used a 103-scaled hexagonal stimulus array that subtended a retinal area of approximately 40° in diameter. The amplitudes and implicit times in each location for the mfERG were compared with the corresponding values determined for a group of 34 normally sighted, age-similar control subjects. Results: Mapping of 103 local electroretinographic response amplitudes within a central 40° area with the mfERG showed regions of reduced mfERG amplitudes in three of six carriers. Implicit time measurements in the 6 carriers were all normal except for those locations associated with abnormal amplitude reductions in 3 of the carriers. When present, retinal dysfunction was evident in the presence of a normal-appearing fundus. Conclusions: Multifocal ERG testing can demonstrate areas of retinal dysfunction in carriers of the BBS. This test may therefore be useful for identifying some heterozygous carriers of this disease.
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