There seems to be a lot of controversy about vision therapy. Why is this?
Vision therapy is a treatment that is generally used for children who are having trouble with reading or in school. This treatment is not usually prescribed by medical doctors (ophthalmologists - MDs) but it is prescribed by optometrists (ODs) who specialize in this area. Many ophthalmologists advise their patients that there is no benefit to vision therapy, and while it is true that there are few randomized, controlled trials that show the benefit, there may be some cases where vision therapy can be helpful. Here at Boston Children's Hospital we offer limited forms of vision therapy, and we are now gearing up to perform studies that will attempt to scientifically validate these treatments.
A subset of optometrists called developmental/behavioral optometrists, have been practicing vision therapy for many decades for tracking, focusing and eye teaming difficulties. There have been only few valid scientific studies addressing the effectiveness of vision therapy and hence limited global acceptance of such treatment options among all vision care professionals. As mentioned by Dr. Hunter, we are in the process of establishing studies that can help further understand the efficacy of vision therapy especially with regard to vision and learning. It is also important to remember that vision is just one component to reading and learning. While it is important to rule out significant vision deficits in children with learning problems, other behavioral, cognitive and social factors to learning must also be sought.
How do I know if I need vision therapy?
In some cases, children who are having difficulty at school will be evaluated by a nurse or occupational therapist and found to have difficulty with eye tracking or other functions. In these cases, the first step is to complete a comprehensive eye examination. If a condition is detected, then a referral for a vision therapy evaluation might be made by the eye doctor.
A comprehensive eye exam and binocular vision evaluation can identify conditions that would benefit from treatment with vision therapy. Some common symptoms of individuals who may benefit from vision therapy (after medical conditions have been ruled out and a normal medical examination of the eye has been completed) include:
Eye strain/eye fatigue with close work (e.g. reading, writing, computer work)
Blurry distance vision after prolonged close work
Losing place while reading
Re-reading lines and/or losing concentration when reading.
Words or letters seem to jump around.
What is "vision therapy"?
Vision therapy is a sequence of eye exercises that are used to improve the quality and efficiency of vision. It is also called vision training. Vision therapy helps your eyes work more efficiently so that you can perform daily tasks, like reading and writing more efficiently.
Is vision therapy the same as orthoptics?
While vision therapy is sometimes referred to as "orthoptics," we do not use the terminology that way. An orthoptist is an individual trained to evaluate the ocular motility and binocular function of patients with strabismus (misaligned eyes). Children's Hospital employs many orthoptists, who work with our ophthalmologists and sometimes prescribe exercises for specific forms of strabismus. Orthoptists do not prescribe other types of vision therapy - that is done by optometrists.
What conditions does vision therapy improve?
Oculomotor problems: Problems with eye tracking skills, including fixation, pursuits and saccades. Fixation refers to the ability to continue looking at a stationary target. Pursuits refer to the ability to continue looking at a moving target. Saccades refer to the ability to smoothly change fixation quickly and accurately from one target to another. For example, saccades are especially important in the act of reading.
Accommodative problems: Problems relating to the focusing system of the eye. Accommodative problems include difficulties focusing accurately during close work and difficulties switching focus from distance to near efficiently.
Vergence problems: Problems with eye teaming abilities. An example of this is convergence insufficiency, which is when the eyes do not work well together. Convergence insufficiency is one of the most common problems that can be treated with vision therapy
What can I expect from vision therapy services?
Vision therapy includes both in-office and home-based exercises. After a problem is identified, a series of exercises will be designed specifically for the individual to improve visual function. A typical program will comprise approximately 6 one-hour sessions of vision therapy scheduled at 3 week intervals. At each in-office session, the patient will be provided with instructions and materials for the exercises that should be practiced at home for about 20-30 minutes per day at least 5 days per week. The final office session is a progress evaluation that assesses the progress made during therapy. At that time it will be determined if more exercises are required.
What sort of research supports the effectiveness of vision therapy?
As mentioned earlier there has been considerable disagreement among professionals about the validity of vision therapy. This is due to inconsistent findings in scientific literature and inadequate study designs. Recently a National Eye Institute (NEI) funded study using multi-center, randomized, double-blind clinical trials showed that for a condition called convergence insufficiency (eye teaming difficulty) office-based vision therapy was successful in 75% of patients, and resulting in normal or significantly improved symptoms. Office-based therapy was found to be more effective than home-based and placebo therapy in children.
While vision therapy clearly helps in amblyopia (wearing an eye patch improves vision in the "lazy" eye) and in convergence insufficiency (as noted by Dr. Raghuram), for the most part there aren't a lot of clinical trials that support this treatment to the point that it has been accepted by the community of ophthalmologists. That said, we do encounter many children who have abnormalities with eye tracking, accommodation, and vergence, and we have seen many patients benefit from some of these treatments. In an effort to try to help children who might be struggling in school because of one of these conditions, we offer evaluation and, in some cases, treatment, or in other cases, referral to tutors or other experts in learning or neuropsychological development. In addition, Dr. Raghuram is currently developing research protocols to compare vision therapy with placebo treatment in patients willing to participate in research. The goal is to someday either validate or disprove many of the common approaches to vision therapy.