Definition of Low Vision
Low vision is defined as an impairment of sight which cannot be adequately corrected with pharmaceutical or surgical interventions, conventional prescription eyewear, or contact lenses. The patient usually presents with a loss of visual field, loss of light sensitivity, distortion, loss of color vision, or loss of contrast. Low vision varies with each individual, and occurs as a result of genetic birth defects, injury, aging, or complication from disease.
What is a Low Vision Specialist?
Low vision specialists are licensed doctors of optometry who are trained in the examination and management of patients with visual impairments. A few of them are ophthalmologists with additional training in low vision care. Their services do not offer a cure for the causes of low vision, but they do help the patient learn how to utilize their remaining vision to its fullest potential. Low vision care does not replace the possible need for other treatments such as laser, medication, and surgery.
Testing by a Low Vision Specialist
Low vision testing goes far beyond regular eye examinations. A careful assessment is made of the patient's vision, while exploring the effect of increasing the size of the image on the retina. Close attention is also given to the effects of decreased vision on the patient's lifestyle, and a plan is designed to meet the patient's needs and goals. A typical low vision examination takes about two hours and is covered by Medicare for qualifying individuals. The exam usually consists of:
1. A look at the patient's history, which can cover hobbies, daily life, educational background, current health, and goals for the future.
2. Testing of vision to make certain that current prescriptions are correct, in addition to an analysis of the patient's ability to see eccentrically, or "off-center." This is particularly useful for macular degeneration patients who have lost the use of their central vision.
3. Introduction of low vision aids for both near and distance viewing, and determination as to which devices will work best for the patient. These devices include magnifiers, closed circuit television systems (CCTVs), and independent living aids. The patient learns how to use these aids, while developing skills to maximize remaining vision.
4. Discussion of recommended adaptations to the patient's home and work environment.
5. Discussion of types of lenses which can help to cut brightness, glare, and ultraviolet rays.
6. Scheduling of a home visit to help set up and demonstrate adaptive equipment, analyze lighting, mark appliances, and/or to inspect for safety.
A visit with a low vision specialist can help a visually-impaired person to lead a fully independent life despite visual restrictions. There are also low vision rehabilitation centers which house teams of low vision specialists, rehabilitation teachers, mobility/orientation specialists, occupational therapists, and other professionals in other areas as needed.
Information for this article
was provided by The Low Vision
Gateway and Dr. Jennifer Hensil, O.D. M.S. For additional
information, see "Finding A Low Vision Specialist" in the MD Support Library
Further information about low vision, go to American Optometric Association