Vision Restorative Therapy Gives Hope To Stroke Survivors
How stroke affects eyesight
The serious damage that stroke inflicts on the brain affects not just motor function, but it may affect vision as well. It is reported that approximately 20% of stroke victims suffer some degree of vision loss, and the number is said to be increasing by 100,000 a year. Vision loss is usually present in the inside edge of one eye- the side nearest the nose – and the outer portion of the other. Difficulty with mobility, reading and clumsiness are often the most serious consequences of vision loss experienced by stroke victims.
Some common types of vision loss in stroke victims:
1. Hemianopia: This is decreased or lost vision in half of the visual field in both eyes
2. Quadrantanopia: Decreased or lost vision in quarter of the visual field in both eyes.
3. Scotoma: Blind spots or “islands” of lost vision.
4. Constriction/tunnel vision: The person sees objects in the center of the visual field, but not around the edges.
5. Diffuse field defects: This causes blurred vision
6. Multiple field loss: Areas of darkness appear to be scattered around objects.
Spontaneous vision recovery following stroke
Some patients may begin to experience improvement in their eyesight within weeks or months following a stroke. This recovery may be the result of reduced swelling in the brain, tissue that is beginning to heal, or improved brain function, allowing it to transmit impulses. However, after three months if no improvement is seen, then the patient needs to be treated.
Fortunately, scientists have discovered that the adult brain is plastic and is therefore subject to change through thought and activity. And there’s more good news. The formation of new cells can occur in the elderly.
How vision restorative therapy works
Based on this knowledge, vision restorative therapy targets undamaged nerve cells in the brain and stimulates them in a specific pattern. Patients may begin therapy at any of the many rehab facilities available in the United States and complete it in their homes. Patients first undergo a diagnostic test to determine the scope of their vision loss. After the results are analyzed, the patient is given a customized computer device to take home. The device can be set up on a desk or table and consists of a monitor with a chin-rest.
The patient focuses his eyes on a specific point on the monitor. Stimuli in the form of dots appear on the monitor, and the patient responds as instructed. The computer emits a sound when the dots are recognized accurately, and another sound if the patient misses the dots. Each session lasts 30 minutes, and patients are encouraged to do two 30-minute sessions daily. With continued exposure to the stimuli, healthy neurons in the brain are activated to improve vision over time. Four to five weeks of treatment make up a module. After each module, the device automatically assesses the patient’s visual field and updates the program to suit his progress. The average length of therapy is six months.
Encouraging results for vision restorative therapy
At the annual meeting of the American Academy of Neurology in 2007, it was reported that 70% of trial participants experienced improved vision after six months of vision restorative therapy. Think of what this means in terms of fewer accidents, improved mobility and an overall improvement in the quality of life for stroke survivors.