Vision therapy
Not all vision problems can be corrected by spectacles or contact lenses. Some people, including many children, have difficulty in co-ordinating their two eyes.
In order to see something clearly, both eyes must be aimed accurately at the object and focussed at the right distance. Any problems with the aiming or focussing of the eyes can cause a variety of symptoms, including intermittent double vision, blurred vision, headaches and feelings of eyestrain. Children with these problems often do not complain about them, but may simply avoid tasks such as reading that are difficult or cause discomfort.
Vision is the process of deriving meaning from what is seen. It involves more than simply visual acuity (the ability to distinguish fine details). Vision involves fixation and eye movementabilities, accommodation (focussing), convergence (eye aiming), binocularity (eye teaming), eye-hand coordination and visual form perception. Vision is not entirely innate but continues to develop after birth and is influenced by the visual environment and the individual's experience. If a person's visual system has not developed to its optimal level, visually demanding activities may lead to inefficient or uncomfortable vision. Good visual acuity and healthy eyes are no assurance that an individual does not have a vision problem.
Vision therapy (also referred to as visual training) is a program aimed at remediating and enhancing an individual's visual abilities. Its function is to:
- treat existing visual problems such as amblyopia (lazy eye), eye alignment problems, eye coordination problems, poorly sustained near focus, inadequate eye-hand coordination and immature perceptual development
- enhance the efficiency and comfort of visual function
- help prevent some visual problems.
Each program of vision therapy must be designed to suit the specific needs of the individual. Diagnostic testing, training procedures and the use of lenses and prisms may be integral components of the successful treatment of a vision problem. The frequency of consultation, the amount of home training and the duration of a course of vision therapy will vary depending on the nature and severity of the problem being treated and the specific needs of the patient.
Vision therapy is not used to strengthen eye muscles, but to improve the coordination and efficient functioning and processing of the visual system.
Orthoptics is another term often used in connection with vision therapy. Orthoptics is one part of a specific vision therapy program directed at improving binocular alignment and visual acuity in individuals with strabismus (turned eye or 'squint') and amblyopia ('lazy-eye').
Approximately half the Australian population has some vision problem requiring treatment. While the majority have refractive errors (shortsightedness, longsightedness, astigmatism andpresbyopia), many people have problems which can be improved or remediated by vision therapy. Although its impact is greatest in children and young adults, vision therapy is effective for patients of any age who may have difficulty utilising their visual system efficiently.
