Every year in the Philippines, thousands of people survive a stroke — the sudden interruption of blood supply to a part of the brain, which results in the death of brain cells. Rapid diagnosis and brain-sparing treatments — such as tissue plasminogen activator (tPA), an enzyme that dissolves blood clots, or other clot-clearing procedures — can limit the damage and resulting disability. But the cells that do die can rob a person of his ability to speak, move, feel, think, or even recognize relatives and friends. About two-thirds of stroke survivors must work to regain abilities — or learn to compensate for the ones they can’t regain — by developing new strengths and strategies.
Many people think of rehabilitation as something that comes after medical treatment of the stroke, but to a large extent the two coincide. Aggressive rehabilitation — started as soon as possible in the hospital — can mean the difference between recovering skills essential to daily living and remaining severely impaired and dependent. Strategies used for decades are the mainstay of rehabilitation, but new approaches and technologies are also gaining ground. What’s more, researchers are learning that improvement is still possible many months, sometimes even years, after a stroke.
Which parts of the brain are affected?
The effects of a stroke depend on which parts of the brain have been damaged (see illustration on Page D-2). For example, cell death in the cerebellum (the lower back part of the brain) can throw off balance and the orchestration of voluntary muscle actions such as those required for walking or opening a package. Damage to Broca’s area, in the frontal lobe and on the left side of the brain in most people, prevents a person from producing articulate speech, even if she understands what’s being said to her or knows what she wants to say. If there is a damage to the Wernicke’s area (in the left temporal lobe), the person doesn’t understand language even though she can articulate words. Generally, a stroke in one hemisphere of the brain interferes with functioning on the opposite side of the body. For example, a right hemisphere stroke might impair the left side of your field of vision (in both eyes) or might make it difficult to lift your left arm or smile with the left side of your mouth.
Depending on its location in the brain, a stroke may produce one or more of the following:
• Paralysis or weakness on one side of the body (called, respectively, hemiplegia and hemiparesis); spasticity (involuntary muscle tightening) that results in a stiff leg or a stiffly flexed elbow and wrist and tightly clenched fist; trouble swallowing (dysphagia); and difficulty coordinating movement (ataxia).
• Sensory changes, such as numbness, aches, and pain.
• Trouble understanding speech (receptive aphasia) or expressing oneself in words (expressive aphasia).
• Cognitive problems such as impaired thinking or memory; shortened attention span; disorientation; inability to recognize faces (prosopagnosia) or work step by step through a task (apraxia); and unawareness or denial of disabilities caused by the stroke (anosognosia).
• Emotional turmoil, such as changes in mood and personality, impulsivity or inappropriate behavior, and bursts of anger. In particular, about 25 percent of people who have a stroke develop major depression, which can undermine rehabilitation and worsen cognitive abilities if left untreated.
Early Recovery And Rehabilitation
After a patient is medically stable (usually within 24 to 48 hours), assessment of function begins. This includes tests of arm and leg strength, memory and comprehension, and the ability to speak and swallow. The assessment may be done by a physician or allied health professionals, who are members of the multidisciplinary rehabilitation team.
Simple steps toward rehabilitation will also begin. Patients are encouraged to shift position frequently in bed and practice simple range-of-motion exercises for an affected arm or leg, both actively (without help) and passively (with assistance of a therapist).
Later, therapeutic plans will be tailored to individual impairments. Initial goals include sitting up and sliding from bed to chair, standing, and walking (with or without help), as well as the ability to perform daily activities, such as dressing, bathing, and eating. Ultimate goals may include a return to work and pleasurable activities. Therapy may take days, weeks, or months.
Physical, Occupational, And Speech Therapy
Stroke rehabilitation takes advantage of spontaneous recovery, which accounts for many of the gains made in the first month after a stroke, and brain plasticity — that is, the brain’s ability to form new connections, develop new neural pathways, or strengthen existing pathways to compensate for those that are damaged. Repetitive actions that reinforce these pathways are the bedrock of physical, occupational, and speech therapy.
During physical therapy, stroke survivors work to regain strength, balance, and coordinated movement, mainly in the legs and trunk. Occupational therapy focuses on specific activities of daily living, such as dressing, writing, feeding oneself, and brushing teeth. Speech and language therapy emphasizes the restoration of verbal expression and comprehension that have been impaired by cognitive deficits or by paralyzed or weakened muscles.
Accumulating research shows that a technique called constraint — induced movement therapy (CIMT) — can speed recovery of some types of movement. CIMT involves restraining the stronger arm to make the weaker one work harder. In the EXCITE (Extremity Constraint-Induced Therapy Evaluation) trial, reported last year in the Journal of the American Medical Association (JAMA), about half of the 222 participants with an arm weakened by a stroke received usual care. The other half exercised the weakened arm intensively for two weeks while wearing a constraining mitt on the other arm. Periodic testing during the year after therapy showed that CIMT participants were better able to use the affected arm in tasks such as turning a key in a lock, folding towels, and lifting a weighted basket.
Advanced Technologies
Advances in robotics are providing new options. One device, called the Locomat, is a set of robotic leggings that puts the legs through walking motions while the patient is positioned on a treadmill and supported by a padded harness. Another device, the FDA-approved Myomo e100 NeuroRobotic System, is a brace wired to pick up weak signals from the patient’s arm muscles and responds by bending or extending the arm. “It’s sort of like power steering,” says Dr. Joel Stein, chief medical officer at Boston’s Spaulding Rehabilitation Hospital. Stein is the lead author of a pilot study of the device published last year in the American Journal of Physical Medicine and Rehabilitation. “You plan the movement, you execute it, but the brace helps you do it,” he explains. By practicing with this device, stroke survivors can often relearn arm movements and strengthen the brain pathways that govern those movements.
Other promising research combines intense, repetitive exercise with electric or magnetic stimulation of the brain aimed at boosting plasticity. On the basis of preliminary studies in animals and humans that suggest these methods can speed neural rewiring, trials of several brain stimulation devices are underway.
Extending The Therapeutic Window
People recovering from a stroke make their greatest gains in the first three to six months. That’s one reason it’s essential to advocate — for yourself or a loved one — for early evaluation and rehabilitation. At the same time, research suggests that improvements may occur many months and even years beyond this window.
Stem cells, growth factors, and other agents that could help in rebuilding injured areas of the brain are being investigated. Such developments are likely to be years away, but many smaller advances that can make a tremendous difference in a stroke survivor’s life — such as stronger and better coordinated hand movements, a more natural walk, or more comprehensive speech — are available today.