Low Vision Rehabilitation
Low vision rehabilitation is like physical therapy for someone who has lost a limb. Its purpose is to develop strategies to maximize or substitute for diminished sight in order to maintain independence and a sense of self-worth. This rebuilding and reinforcement of the visual foundation is accomplished through identification of goals, introduction to assistive devices, and training. Rehabilitation is not just an introduction to low vision devices. Actually, that may not occur until some time into the program, after the patient has gone through evaluation and training. Only then can appropriate recommendations for low vision devices be made.
Depending upon the patient’s needs, a good program might also provide education, support groups, and individual counseling. It would help the patient to realize that using such devices and techniques is a sign of tenacity and courage, not weakness or defeat.
People with a constricted visual field might expect to be introduced to scanning therapy and devices such as visual field awareness prisms and reverse telescopes. People with severe vision loss should expect to receive orientation and mobility training, occupational therapy, and information about animal guides and occupational therapy.
In addition to these skills, vision rehabilitation specialists teach how to manage daily activities such as:
- adapting the home for safety and navigation
- improving lighting conditions
- preparing meals
- labeling medications, clothing, and appliances
- keeping financial records
- personal grooming
- using magnifiers for easier reading
- systematizing shopping and payment at the register
Why Is Low Vision Rehabilitation Necessary?
There are some very good reasons for low vision rehabilitation, the most important being increased physical and psychological health. Research has shown that people with low vision tend to have more emotional difficulties and a higher risk of accidents than normally-sighted individuals. Patients who have undergone rehabilitation, however, have reported significant improvements in their functional abilities, a high rate of continued use of low vision devices, improvement in reading and distance vision, and general satisfaction with the quality of life.
The first step in the rehabilitation process is working one-on-one with a counselor or specialist who will assess the client’s needs and identify which programs are best suited to meet them. After an appointment is scheduled, a low vision therapist asks questions about the client’s health, eye condition, and visual goals.
The next step is assessment of visual functions through tests and techniques adapted to fit the client’s visual impairment.
Visual acuity and refractive status are tested using special low vision refractive techniques. These tests make use of larger-than-usual testing charts, control of illumination, trial frame refraction, and techniques that allow for eccentric (off-center) viewing. The tester will also use an Amsler grid, a simple way to identify defects in the central visual field. Tests will include some, but not necessarily all, of the following:
- A contrast sensitivity test can determine the client’s ability to discriminate subtle changes in vision that occur in the real world, rather than the absolute black-on-white contrast of visual acuity charts.
- A brightness acuity tester, or BAT, measures the impact of glare on the retina.
- A color vision test can determine possible functional implications.
- An ocular motility test can identify any problems with impaired eye movement.
A visual field test can predict how the client might function in day-to-day activities and how well he or she might respond to various rehabilitative approaches. Four types of visual field tests are available for this purpose:
- A tangent screen test, during which the client identifies a spot of light moving into the peripheral field.
- A confrontations test, wherein the doctor introduces objects such as fingers or lights from the side to see if there are any large field defects like loss of side vision to one side due to stroke. This test is not sensitive to small or slight changes in the vision.
- A perimeters test, wherein lights or other targets are presented to the patient in various positions. In a manual perimeters test, the doctor controls the target movement and speed of the target and maps out the field loss areas.
- A computerized perimeters test, wherein a computer program presents a specific pattern of lights and then prints out the results with analysis.
Finally, to ensure that there were no other ocular diseases or complications, the client should be given an external eye health evaluation, an intraocular pressure reading, and an internal eye exam through dilated pupils.
Training sessions will be scheduled, typically twice a week for six weeks, with each session lasting one or two hours. The first session will yield a list of personal visual goals that will give direction to the training. These goals are in the areas of activities of daily living (often called independent living skills), computer use, and counseling.
Vocational rehabilitation might be part of the program if the client needs to remain employed. If that is the case, several psychometric assessments would be made to evaluate current skills as they relate to the employment.
If the client’s condition is severe enough, orientation and mobility training might also be included. A person with nearly total vision loss would require about 25 hours of individualized sessions by an O&M specialist, with advanced training in actual public situations. The activity would also include several hours of calisthenics and walking. Skills such as safe street crossings, negotiating stairs and curbs, and utilizing public transportation would be learned, in addition to familiarization with new environments. Use of an animal guide would also be an important consideration, as would training in Braille.
Training might begin with safe cooking strategies, labeling techniques, use of adaptive equipment, and an evaluation of the safety and lighting in the home. Most of this will likely take place in a supervised program of self-care using a specially-designed apartment at the center.
Finally, personal adjustment counseling and marital counseling might be undertaken to help the client and the client’s family to deal with the challenges of visual impairment. Direct lines of communication should be constantly maintained between the rehabilitation center’s staff, the state sponsoring agency, the client, and the family.
For patients with mild vision loss, simple environmental modifications may be enough to perform daily living tasks. People with moderate to severe visual loss will also benefit from environmental modifications, but they will need additional experience with low vision devices and technology to help maximize their vision.
Four factors are taken into consideration when analyzing and modifying the client’s home: illumination, glare, contrast, and figure-ground perception.
The client will learn that magnification of both near and distant images can improve visual function in nearly everyone with central vision loss. A variety of magnification devices, both optical and non-optical, will be introduced.
In order to select the most appropriate low vision devices, the specialists will:
- Identify exactly what tasks the client wants to accomplish.
- Analyze the client’s fine and gross motor skills to confirm his or her ability to operate the low vision devices.
- Determine which eye is dominant.
- Determine whether monocular or binocular vision would be better.
- Determine whether the client would benefit from practicing eccentric (off-center) viewing.
- Determine if illuminated magnifiers are necessary.
- Clinical trials: These are research studies evaluating how effective a medical, surgical, or behavioral intervention will work in people.
- Control group: In a clinical trial, this group receives a standard treatment, a placebo, or no treatment at all.
- Dosage: The amount of the drug or treatment needed.
- Dose-ranging, or dose-escalation trial: A clinical trial designed to decide what is the best drug dosage and if there are side effects. All participants would receive the treatment/therapy, but in differing amounts.
- Double-masked study: This is a clinical trial that neither you nor the study doctor knows which treatment group you are assigned to (control group or experimental group).
- Experimental group: In a clinical trial, this group receives the treatment or therapy that is being tested.
- Open label study: This is a clinical study where both the study doctor and you both know which treatment you are receiving.
- Protocol: Clinical trials follow a careful a plan of action that describes exactly what the study doctor will do as part of the study.
- Single-masked study: This is a clinical trial where you do not know your treatment group but the study doctor does know your group assignment.
- Trial center: A trial center is where clinical trial testing occurs at one or multiple locations around the country provided by study-approved doctors.
Finding a Low Vision Rehabilitation Center
The ideal center offers comprehensive programs with teams of occupational therapists trained in visual rehabilitation, vocational rehabilitation counselors, vision rehabilitation therapists, orientation and mobility specialists, psychologists, assistive technology computer specialists, and other professionals as needs dictate.
Such teams can be found in some university centers and large private clinics. Rehabilitation services may also be provided by local charitable organizations. All state governments in the United States fund an agency to coordinate the visual rehabilitation of its visually impaired citizens. They take care of most of the rehabilitative efforts, either directly or through subcontractors. Called either “Rehabilitation Services for the Blind” or “Commissions for the Blind,” these organizations can be found listed by state in the Resources section of this website.
In cases where a person might not meet the eligibility requirements of the state blindness agency, but the person’s employment is being adversely affected, they can go for help to the state’s vocational rehabilitation agency, also listed in PBA resources.
Paying for Low Vision Rehabilitation
How does one get help, and how is it paid for? The referral mechanism differs slightly with each state, but generally, a referral can be requested by any individual, family, friend, eye care professional, rehabilitation specialist, or social worker.
State statutes specify the minimum levels of vision loss for entry into the program, but there is also some flexibility in the acceptance standards. A doctor must provide documentation of the best-corrected visual acuity and/or the visual field in each of the patient’s eyes.
State agencies will usually cover the costs of rehabilitation for people who are registered. Those who are not qualified for government assistance might expect to pay their own expenses.
Government agencies do the best they can with the limited funds available, and private or non-profit organizations help to fill the gap. The task, however, is much larger than current budgets and resources allow.
Vision impairment is one of the four leading causes of lost independence among older people, with annual costs for medical and long term care in the billions of dollars. Low vision rehabilitation can cut these costs considerably by helping to restore functional abilities, safety, and independence.
Author: Dan Roberts, MME (Macular Degeneration Support)
Roy Gordon Cole, OD, FAAO (Jewish Guild Healthcare, New York, NY)
Brian Gerritsen, MA, CLVT (Low Vision Rehabilitation Services, North Ogden, UT)
Joseph Maino, OD, FAAO (VICTORS Low Vision Rehabilitation Program, Kansas City VA Medical Center)
Clay Berry (Alphapointe Center for Blindness and Low Vision, Kansas City, MO)
1. L. David Ormerod, MD, Sue Mussatt, RN, and Associates (authors: Low Vision Assessment and Rehabilitation, School of Health Professions and School of Medicine, University of Missouri, Columbia)
2. Richard L. Windsor, O.D., F.A.A.O. and Laura K. Windsor, O.D. (authors, Low Vision Rehabilitation: An Introduction, published in the Rehabilitation Professional Journal, Spring 2001)
3. The Cost of Vision Problems at Prevent Blindness America. Retrieved 2013.