The role of occupational therapy in vision rehabilitation of individuals with glaucoma

Are rehabilitation professionals familiar with visual impairments? A survey of professional orders in Quebec, Canada

SIGNIFICANCE

The number of patients with mild to moderate visual impairments (MVIs) is increasing as the average age of the population increases. Thus, it is important to understand the training and resources available for rehabilitation practitioners to provide adequate care to these patients within their scope of practice.

PURPOSE

This study explores rehabilitation professionals' perceptions of their competence in screening and treating patients with MVI, and identifying the tools and resources needed to increase these professionals' comfort level in managing these patients.

METHODS

Data collection was carried via an online questionnaire to Quebec rehabilitation professionals and student-trainees who are members of their respective professional orders. The questionnaire consisted of 29 to 30 questions (open- and close-ended) related to demographics, service provision to MVI patients, education in MVI and future training, and future service delivery to MVI patients.

RESULTS

Data were collected from 96 professionals, with 52 fully completing the questionnaire, with all the responses included in the analysis. Most respondents had little or no confidence in adequately screening or treating patients with MVI and mentioned that they knew little or nothing about the range of services offered by vision rehabilitation centers in Quebec (81%), whereas 55% at least occasionally offer services to these patients. The majority felt that their profession would benefit from continuing education on MVI (73%), with a marked interest in online training.

CONCLUSIONS

Rehabilitation professionals in Quebec are not confident in identifying or treating patients presenting MVI but express an interest in attending continuing education courses given by optometrists, low vision professionals, or a member of their own profession. Numerous barriers account for this problem, including a lack of experience and competence in the assessment and treatment options for MVI, as well as a lack of informational and human resources available in their workplaces.

Approaching rehabilitation in patients with advanced glaucoma

Vision loss from advanced glaucoma is currently irreversible and impairs functional visual ability to effectively perform everyday tasks in a number of distinct functional domains. Vision rehabilitation strategies have been demonstrated to be effective in low vision populations and should be utilized in persons with advanced glaucoma to reduce disability and improve quality of life. Initial challenges to rehabilitation include an incomplete understanding of vision rehabilitation by the physician and patient, motivation to integrate rehabilitation into the plan of care, and availability of suitable providers to deliver this care. Physicians, working with well-trained vision rehabilitation providers can maximize function in important visual domains customized to the patient based on their needs, specific complaints, severity/pattern of visual damage, and comorbidities. Potential rehabilitative strategies to be considered for reading impairment include spectacle correction, visual assistive equipment, and sensory substitution, while potential strategies to facilitate driving in those deemed safe to do so include refractive correction, lens design, building confidence, restriction of driving to safer conditions, and avoiding situations where cognitive load is high. Mobility is frequently disrupted in advanced glaucoma, and can be addressed through careful distance refraction, behavior modification, home modification, mobility aids, walking assistance (i.e., sighted guide techniques), and smartphone/wearable technologies. Visual motor complaints are best addressed through optimization of lighting/contrast, sensory substitution, IADL training, and education. Special rehabilitative concerns may arise in children, where plans must be coordinated with schools, and working adults, where patients should be aware of their rights to accommodations to facilitate specific job tasks.

Distracted Driving and Driving Patterns in Older Drivers With Glaucoma

Limited research exists examining self-perceived vision and driving ability among individuals with glaucoma, and this study assessed the relationship between glaucoma, visual field, and visual acuity with driving capability.

137 individuals with glaucoma and 75 healthy controls were asked to evaluate self-rated vision, self-perceived driving ability, and self-perceived distracted driving. Visual acuity and visual field measurements were also obtained. Multivariable linear regressions were run to test each visual measure with driving outcomes.

The average age was 72.2 years, 57.3% were male, and 72.5% were White. There were significant associations for a one-point increase in visual field and quality of corrected vision (RR = 1.06; 95% CI = 1.03–1.10), day vision (RR = 1.05; 95% CI = 1.03–1.08), night vision (RR = 1.08; 95% CI = 1.05–1.13), visual acuity score and higher quality of corrected of vision (RR = .41; 95% CI = .22-.77), day vision (RR = .39; 95% CI=.22–.71), and night vision (RR = .41; 95% CI = .18–.94); visual acuity score and ability to drive safely compared to other drivers your age (RR = .53; 95% CI = .29–.96).

Individuals with poorer visual acuity and visual fields rate their vision and ability to drive lower than those with better vision, and this information will allow clinicians to understand where to target interventions to enhance safe driving practices.

Predicting artificial visual field losses: A gaze-based inference study

Visual field defects are a world-wide concern, and the proportion of the population experiencing vision loss is ever increasing. Macular degeneration and glaucoma are among the four leading causes of permanent vision loss. Identifying and characterizing visual field losses from gaze alone could prove crucial in the future for screening tests, rehabilitation therapies, and monitoring. In this experiment, 54 participants took part in a free-viewing task of visual scenes while experiencing artificial scotomas (central and peripheral) of varying radii in a gaze-contingent paradigm. We studied the importance of a set of gaze features as predictors to best differentiate between artificial scotoma conditions. Linear mixed models were utilized to measure differences between scotoma conditions. Correlation and factorial analyses revealed redundancies in our data. Finally, hidden Markov models and recurrent neural networks were implemented as classifiers in order to measure the predictive usefulness of gaze features. The results show separate saccade direction biases depending on scotoma type. We demonstrate that the saccade relative angle, amplitude, and peak velocity of saccades are the best features on the basis of which to distinguish between artificial scotomas in a free-viewing task. Finally, we discuss the usefulness of our protocol and analyses as a gaze-feature identifier tool that discriminates between artificial scotomas of different types and sizes.

Head-Mounted Display Technology for Low-Vision Rehabilitation and Vision Enhancement

PURPOSE

To describe the various types of head-mounted display technology, their optical and human-factors considerations, and their potential for use in low-vision rehabilitation and vision enhancement.

DESIGN

Expert perspective.

METHODS

An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field.

RESULTS

Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low-vision aids. Devices vary by their relationship to the user's eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion, and user interface. These optical and human-factors considerations are important when selecting head-mounted displays for specific applications and patient groups.

CONCLUSIONS

Head-mounted display technologies may offer advantages over conventional low-vision aids. Future research should compare head-mounted displays with commonly prescribed low-vision aids to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations.