© Springer International Publishing Switzerland 2015Ingrid Söderback (ed.)International Handbook of Occupational Therapy Interventions10.1007/978-3-319-08141-0_32
32. Teaching/Learning Strategies for Intervention with People with Neurovisual Impairments
School of Health Professions, Department of Occupational Therapy, Virginia Commonwealth University, 730 East Broad Street, 23219 Richmond, VA, USA
This chapter presents teaching/learning strategies that can be used by occupational therapists (OTs) who provide service for people with neurovisual impairments, i.e., vision impairments related to neurological injury and illness. When to consider integrating people with neurovisual impairments into group interventions that primarily include people with adult-onset eye diseases such as macular degeneration and glaucoma is discussed. When it is probably most essential to provide individual intervention is also discussed. There is a focus on self-management and health promotion models to design and plan both group and individual interventions.
The term, neurovisual deficit, incorporates all vision problems occurring as a result of neurological disorders, such as brain injury or multiple sclerosis . Specifically defined, neurovisual deficits are post-chiasmatic visual field and central field disorders, i.e., disorders of the central nervous system occurring proximal to the optic chiasm (Kerkhoff 2000).
Symptoms of neurovisual deficits can be classified as problems with accommodation , version (synchronous and symmetric eye movement), vergence (synchronous eye movement in asymmetric directions), visual fields, and light absorption and modulation. A number of problems with vision fall into these categories including, problems with fixation, scanning, and reading speed; double vision, shimmering vision, and eye strain; spatial awareness; and problems with light sensitivity, contrast sensitivity, and color detection (Kerkhoff 2000). Visual field deficits are frequently seen in people with neurovisual deficits. Other symptoms that are often encountered include severe spatial–perceptual deficits such as depth perception and hemi-inattention or unilateral neglect. Impaired oculomotor control and, in rare cases, visual hallucinations can also be present (Kerkhoff 2000; Rowe et al. 2009).
Complications to the treatment of neurovisual deficits are often in relation to the overall impact of acquired brain injuries including intellectual and motor problems (Whitson et al. 2007). They can limit a person’s potential for using assistive technology interventions designed for the larger low-vision population and may require the use of more detailed learning strategies to assure ongoing use. In particular, the presence of any intellectual disability presents a challenge to teaching and learning compensatory strategies for neurovisual deficits; the greater the intellectual challenge, the more time and effort it will take for the client and therapist to develop strategies that compensate for the vision impairment. Within the category of neurovisual deficits, there are symptoms that are not uniquely visual but rather are manifestations of multiple sensory losses, frequently in combination with intellectual and motor problems, hemispatial neglect being a primary example. Neurovisual deficits range from mild to severe, and therefore, can affect occupational performance in a variety of ways (Warren 2011b).
People with neurovisual deficits require occupational therapy intervention in the customized use of assistive technologies, adaptation of the environment, and adapted performance of daily activities to assure ongoing performance of occupations. Occupational therapists (OTs) are knowledgeable of neurological illness and disability, as well as vision disorders. They are skilled in the treatment of acquired brain injuries and other neurological disorders, and they are trained to explore the use of assistive technologies, adapt environments, recognize challenges of desired tasks, and explore adjustments to permanent physical changes with clients for whom such intervention will enhance occupational performance. This chapter focuses on the learning strategies that are beneficial for the people with neurovisual deficits.
Candidates for Interventions
All people with neurological illness and disability should be screened and evaluated for vision problems. Problems with vision in this population can be detected through the use of vision assessments such as the Brain Injury Visual Assessment Battery for Adults (Warren 2013b), the Self-Report Assessment of Functional Visual Performance (SRAFVP; Mennem et al. 2012), and the Melbourne Low Vision ADL Index (MLVAI; Haymes et al. 2001). Most candidates for intervention are people with mild to moderate acquired brain injuries and other neurological disorders who complain of or demonstrate problems specific to the visual system, including inability to recognize objects in visual fields, create meaning from what they see, and take appropriate action to complete a task or solve a problem that would typically be discerned through visual information. People with more severe acquired brain injuries and other neurological diseases are not to be discounted. As recovery occurs, the ability to make use of assistive technologies and other strategies to compensate for vision problems can improve with intervention (Warren 2013a).
While there are estimates that vision impairment accompanies acquired brain injury in around 30 % of cases (Kerkhoff 2000), neither national nor international statistics on the incidence and prevalence of low vision and blindness due to neurovisual deficits have been determined. One study examining prevalence and cause of vision impairment calculated the frequency of visual field deficits. In this single-site, retrospective study of 220 people with acquired brain injuries (traumatic brain injury and stroke) , 46 % were found to have some form of visual field deficit. Among those, approximately one fourth had scattered visual field deficits (Suchoff et al. 2008).
Settings and Services for People with Neurovisual Deficits
Vision rehabilitation services for people with neurovisual deficits are provided in a wide variety of contexts and settings. Initial evaluation to detect vision problems in the hospital where the person is receiving care for the overarching neurological disorder increases the potential for service-specific to the neurovisual deficit. In inpatient rehabilitation settings, referral to ophthalmologists and optometrists, frequently initiated through occupational therapy screening and observation, often leads to valuable intervention for people with neurovisual deficits. If more vision services are needed following inpatient stages of treatment, outpatient care may be necessary.
Low vision services for people with acquired eye disease are typically provided on an outpatient basis in specialized low-vision rehabilitation programs. These are available via departments and ministries of vision and blindness or in private ophthalmology and optometry practices that employ low-vision specialists. Many of the services available from these programs are for blind adults and children with congenital or early-onset blindness and vision impairments, but it is becoming more common in some countries for people with adult-onset eye diseases and neurovisual deficits to be referred to these programs. In the USA, while state vision and blindness departments make efforts to accommodate individuals with neurovisual deficits, many of these services are provided through hospital-based occupational therapy programs or low-vision rehabilitation programs by a team of specially trained physicians and OTs. In all settings, availability of other needed service, including social work, psychology, nursing, and orientation/mobility is an important part of the context and setting. Collaboration between OTs and other vision rehabilitation professionals assures appropriate care and expands the impact of intervention (Warren 2011a).
Service is provided in both individual and group formats. In most inpatient occupational therapy settings, vision rehabilitation services for a person with an acquired brain injury or other neurological disorder are provided individually as part of an intervention plan that addresses a broader focus on functional retraining following the neurological disorder, for example, stroke or traumatic brain injury . Remediation of vision problems occurs through referral to neuro-ophthalmologists. When the vision problem is more closely related to visual perceptual and visuocognitive issues and when these problems are severe, individual intervention is more likely to be successful. In cases of mild neurovisual symptoms, intervention may proceed via individual or group formats. People with mild neurovisual symptoms may benefit from group interventions with a health promotion or self management perspective. Participants in group programs like these are typically people with low vision from eye diseases like macular degeneration or retinopathy, but they can accommodate people with mild to moderate neurovisual deficits as well.
The Role of the OT
The main challenge to the OT working with people with neurovisual deficits is to determine, through screening and evaluation , the extent to which vision problems directly deplete the functional abilities. In addition, the therapist tries to discern how vision contributes to problems with cognitive processing. Once vision-related issues are identified, the OT must arrange for and follow through with any remedial interventions the client might need to improve function. The OT must also explore compensatory strategies that simplify and accommodate daily function. The OT partners with the client to facilitate problem solving, decision making, and the most appropriate use of low vision resources. Primary areas of focus in the rehabilitation of people with neurovisual deficits are reading and learning to explore the visual field deficit area. Hemianopic dyslexia, a severe reading disorder manifested by slow reading, omission of words, word guessing, and disorganized scanning patterns, can be reduced through guided reading practice and instruction in exploration of the deficit visual field. OTs can provide such training directly and during performance of functional activities like following a menu or preparing a grocery list (Schuett et al. 2012).