Vision therapy (VT), or behavioral optometry, is an umbrella term for alternative medicine treatments using eye exercises, based around the pseudoscientific claim that vision problems are the true underlying cause of learning difficulties, particularly in children. Vision therapy has not been shown to be effective using scientific studies, except for helping with convergence insufficiency. Most claimsfor example that the therapy can address neurological, educational, and spatial difficultieslack supporting evidence. Neither the American Academy of Pediatrics nor the American Academy of Ophthalmology support the use of vision therapy.
Definition and conceptual basis
Vision therapy is based on the proposition that many learning disabilities in children are based on vision problems, and that these can be cured by performing eye exercises. Vision therapy lacks sound evidence, has been characterized as a pseudoscience and its practice as quackery.
Vision therapy is a broad concept that encompasses a wide range of treatment types. These include those aimed at convergence insufficiency – where it is often termed "vergence therapy" or "orthoptic therapy" – and at a variety of neurological, educational and spatial difficulties.
Efficacy
There is no good evidence that vision therapy of any benefit in treating learning disabilities, reading, dyslexia, or ADHD, although there is some evidence that it may help treat convergence insufficiency in healthy people. the consensus among ophthalmologists, orthoptists and pediatricians is that non-strabismic visual therapy lacks documented evidence of effectiveness.
A review in 2000 concluded that there were insufficient controlled studies of the approach. A 2008 review of the literature also noted that there were insufficient controlled studies, and concluded that the approaches "are not evidence-based, and thus cannot be advocated."
There is no good evidence supporting the use of vision therapy in the rehabilitation of patients with mild traumatic brain injury, although it may be useful for the treatment of post-traumatic convergence insufficiency and accommodative insufficiency.
Treatment types
There exist a few different broad classifications of vision treatment philosophies, which have been traditionally divided between optometrists, ophthalmologists, and practitioners of alternative medicine.
Orthoptic vision therapy, also known as orthoptics, is a field pertaining to the evaluation and treatment of patients with disorders of the visual system with an emphasis on binocular vision and eye movements. Commonly practiced by orthoptists, optometrists, behavioral optometrists, pediatric ophthalmologists, and general ophthalmologists, traditional orthoptics addresses problems of eye strain, visually induced headaches, strabismus, diplopia and visual-related skills required for reading.
Behavioral vision therapy, or visual integration vision therapy (also known as behavioral optometry).
There have been a number of alternative vision therapy approaches which have not been studied in traditional or evidence-based medicine. They are commonly provided by unlicensed professionals, although a minority of optometrists also provide them. These methods are commonly under scrutiny by ophthalmological and optometric journals for lack of proven effectiveness.
Orthoptic vision therapy
Orthoptics emphasises the diagnosis and non-surgical management of strabismus (wandering eye), amblyopia (lazy eye), and eye movement disorders. Evidence to support its use in amblyopia is unclear as of 2011.
Much of the practice of orthoptists concerns refraction and muscular eye control. Orthoptists are trained professionals who specialize in orthoptic treatment. With specific training, in some countries orthoptists may be involved in monitoring some forms of eye disease, such as glaucoma, cataract screening, and diabetic retinopathy.
Behavioral vision therapy
Behavioral vision therapy (BVT) aims to treat problems including difficulties of visual attention and concentration, which behavioral optometrists classify as visual information processing weaknesses. These manifest themselves as an inability to sustain focus or to shift focus from one area of space to another. Some practitioners assert that poor eye tracking may impact reading skills, and suggest that vision training may improve some of the visual skills helpful for reading.