virtual reality (VR) systems

Virtual Reality - New Steps in Stroke Rehabilitation

By Nirupama Shankar, PT, MHS

Cerebrovascular accident (CVA or stroke) is one of the leading causes of death and disability in the USA; each year about 700,000 people sustain a stroke across the country. Based on the location and size of the lesion, there may be severe and permanent loss of function. The most significant residual effects of a CVA are related to paralysis (hemiplegia), speech disabilities (apraxia, aphasia), and neglect of the affected side. Unilateral neglect is a condition where the patient is unable to identify or respond to any sensory on the affected side of the body; and is more common is a right-sided CVA.
For a large part of the previous century, it was believed that people with stroke would have to lead a largely dependent life, confined to the wheelchair. They were even discouraged from moving their limbs or exercising. Over the years, rehabilitation for patients with stroke has come a long way. Focus has shifted from basic interventions utilizing strengthening exercises to more advance techniques based on the theories of motor learning and neuroplasticity. This included manual techniques by skilled clinicians as well as the use of equipment such as electrical stimulation modalities, and specialized bikes and treadmill systems — all aimed at optimizing function in patients with impairments. In the past few years, a major step for the field of rehabilitation has been the integration of fields such as assistive technology, robotics and computer sciences with the science of rehabilitation. The amalgam of the above has led to potentially powerful systems that will enhance the functional outcome in patients greatly. The latest entrant into the filed of rehabilitation is virtual reality (VR) systems for rehabilitation. Many of the systems have been tested, released and are now available to hospitals and clinics for use. Clinical trials are ongoing, for upgrading existing technology and for invention of new systems for recovery and rehabilitation.
In 2002, the engineers at Rutgers University have created a VR system that included therapeutic activities aimed at recovery of function in patients with stroke. There are now many versions of this system available, and clinical trials are ongoing to evaluate the extent of efficacy of these systems in recovery of function. Like any VR gaming system, patients will see themselves in a simulated environment. Only, games will be replaced by targeted exercises that will work target various functional muscle groups in the arms and hands. Patients can complete fine motor tasks such as picking up objects, stacking objects, and gross motor tasks such as tapping balloons, catching objects and even reach for objects out of their base of support, thus encouraging balance retraining.
Of late, VR rehabilitation systems are also being evaluated for their use in decreasing neglect in patients with hemiplegia. This is achieved by the system providing visual cues from the affected side, to increase awareness and enhance adaptive relearning. A recent published case study (four participants) suggested that VR systems had the potential for decreasing neglect in patients with stroke. In addition to improvements on the objective tests that were administered, participants also subjectively reported that VR training sessions were helpful and enjoyable. VR systems can even simulate day-to-day situations like crossing a street, cooking, opening doors, etc. This will provide very specific learning of the tasks that are essential activities of daily living. The VR systems are effective as they emphasize active participation by the patient and provide varied environments for task practice while providing immediate feedback of quality. All of these fulfill the requirements of ideal motor practice and motor learning.
Stroke survivors, in my experience, are people who have the most enthusiasm to recover; their zest to go back to doing things they used to love serves as a wonderful motivator at rehabilitation sessions. Preserved cognition, high motivations levels, and a firm conviction to go back to their old routine makes patients with stroke ideal candidates for unique rehabilitation tools. I look forward to the day when these systems are available to most hospitals at an affordable price, with simpler user interfaces so that more and more patients will benefit from the systems.



Reference
Smith, J., Hebert, D., Reid, D. (2007). Exploring the effects of virtual reality on unilateral neglect caused by stroke: Four case studies. Technology and Disability, 19(1), 29-40