Vision therapy explained

Vision therapy
Field:Optometry

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.[1] [2]

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.[3] [4]

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.[5]

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.[6] [7] the consensus among ophthalmologists, orthoptists and pediatricians is that non-strabismic visual therapy lacks documented evidence of effectiveness.[8]

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."[9]

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.[10]

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.[11] 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).[12]

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

See main article: Orthoptics. Orthoptics emphasises the diagnosis and non-surgical management of strabismus (wandering eye), amblyopia (lazy eye), and eye movement disorders.[13] Evidence to support its use in amblyopia is unclear as of 2011.[14]

Much of the practice of orthoptists concerns refraction and muscular eye control.[15] 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.[16]

Behavioral vision therapy

Behavioral vision therapy (BVT) aims to treat problems including difficulties of visual attention and concentration,[17] 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.[18] 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.[19]

Behavioral vision therapy is practiced primarily by optometrists who specialize in the area. Historically, there has been some difference in philosophy among optometry and medicine regarding the efficacy and relevance of vision therapy, although none support its use in treating learning disorders. Major organizations, including the International Orthoptic Association and the American Academy of Ophthalmology, have concluded that there is no validity for clinically significant improvements in vision with BVT, and therefore do not practice it.[9] However, major optometric organizations, including the American Optometric Association, the American Academy of Optometry, the College of Optometrists in Vision Development, and the Optometric Extension Program, support the assertion that non-strabismic visual therapy does address underlying visual problems which are claimed to affect learning potential. These optometric organizations are careful to distinguish, though, that vision therapy does not directly treat learning disorders.[20]

Behavioral optometry

Behavioral optometry is a scientifically unproven branch of optometry that explores how visual function influences a patient's day-to-day activities. Vision therapy is a subset of behavioral optometry. In general, vision therapists attempt to improve the vision, and therefore day-to-day well-being, of patients using "eye exercises," prism, and lenses, with more emphasis on the patient's visual function.

Among schools of medicine, ophthalmology does not see merit in the procedures surrounding many of behavioral optometry's practices, as there have not been enough studies of high enough rigor to warrant practicing vision therapy. According to the American Association for Pediatric Ophthalmology and Strabismus, the behavioral aspects of vision therapy are considered scientifically unproven.[8]

Techniques

In 2008, vision scientist Brendan Barrett published a review of behavioral optometry at the invitation of the UK College of Optometrists. He wrote that behavioral optometry was not a well-defined field but that proponents believed it could go beyond standard programmes, like an extension to optometry, taking a holistic approach. Barrett enumerated the therapies:[9]

Barrett noted the lack of published controlled trials of the techniques. He found that there are a few areas where the available evidence suggest that the approach might have some value, namely in the treatment of convergence insufficiency, the use of yoked prisms in neurological patients, and in vision rehabilitation after brain disease or injury—but he found that in the other areas where the techniques have been used, i.e., the majority of situations, there is no evidence of their value.[9] In contrast, Steven Novella points out that the only condition for which there is good quality scientific evidence is convergence disorders. This points out a problem that is common with Complementary or integrative medicine, a type of Alternative medicine, is that a promising use for treating a single disorder is applied to a wide range of disorders for which there is no evidence.[4]

Eye exercises

The eye exercises used in vision therapy can generally be divided into two groups: those employed for "strabismic" outcomes and those employed for "non-strabismic" outcomes, to improve eye health.Ophthalmologists and orthoptists do not endorse these exercises as having clinically significant validity for improvements in vision. Usually, they see these perceptual-motor activities being in the sphere of either speech therapy or occupational therapy.

Some of the exercises used are:

Eye exercises used in behavioural vision therapy, also known as developmental optometry, aim to treat problems, including difficulties of visual attention and concentration, which may manifest themselves as an inability to sustain focus or to shift focus from one area of space to another.

Some of the exercises use:

Fusional amplitude and relative fusional amplitude training are designed to alleviate convergence insufficiency. The CITT study (Convergence Insufficiency Treatment Trial) was a randomized, double-blind multi-center trial (high level of reliability) indicating that orthoptic vision therapy is an effective method of treatment of convergence insufficiency (CI). Both optometrists and ophthalmologists were coauthors of this study. Fusional amplitude training is also designed to alleviate intermittent exotropia[24] and other less common forms of strabismus.

Certain do-it-yourself eye exercises are claimed by some to improve visual acuity by reducing or eliminating refractive errors. Such claims rely mainly on anecdotal evidence, and are not generally endorsed by orthoptists, ophthalmologists or optometrists.[25] [26]

The German optician Hans-Joachim Haase developed a method to correct an alleged misalignment. His method, called the MKH method, is not recognized as an evidence-based approach.[27] [28] [29] [30]

Conceptual basis and effectiveness

Behavioral optometry is largely based on concepts that lack plausibility or which contradict mainstream neurology, and most of the research done has been of poor quality.[31] As with chiropractic, there seems to be a spectrum of scientific legitimacy among practitioners: at one extreme there is some weak evidence in support of the idea that myopia may be affected by eye training;[9] at the other extreme are concepts such as "syntonic phototherapy" which proposes that differently colored lights can be used to treat a variety of medical conditions.[31]

A review in 2000 concluded that there were insufficient controlled studies of the approach.[32] In 2008 Barrett concluded that "the continued absence of rigorous scientific evidence to support behavioural management approaches, and the paucity of controlled trials, in particular, represents a major challenge to the credibility of the theory and practice of behavioural optometry."[9]

Behavioral optometry has been proposed as being of benefit for children with attention deficit hyperactivity disorder and autism – this proposal is based on the idea that since people with these conditions often have abnormal eye movement, correcting this may address the underlying condition. Evidence supporting this approach is, however, weak; the American Academy of Pediatrics, the American Academy of Ophthalmology and the American Association for Pediatric Ophthalmology and Strabismus have said that learning disabilities are neither caused nor treatable by visual methods.[33]

Sports vision training

Practitioners of sports vision training claim to be able to enhance the function of an athlete's vision beyond what is expected in individuals with already healthy visual systems.[34] [35]

History

Various forms of eye exercises have been used for centuries.[36] The concept of orthoptics was introduced in the late nineteenth century for the non-surgical treatment of strabismus. This early and traditional form of vision therapy was the foundation of what is now known as orthoptics and was based on observation not research or evidence.[37]

In the first half of the twentieth century, orthoptists, working with ophthalmologists, introduced a variety of training techniques mainly designed to improve ocular alignment. In the second half of the twentieth century, vision therapy began to be used by specially trained optometrists to treat conditions ranging from uncomfortable vision (asthenopia), ocular motor skills, focusing control, binocular vision, depth perception, eye-hand coordination and visual processing. These treatments have been demonstrated to help many patients with poor reading and academic performance caused by their vision. There are many unscientific techniques promoted commercially and claimed specifically to improve eyesight and even to improve athletic performance.

Behavioral optometry

Behavioral optometry is considered by some optometrists to have its origins the teachings of Skeffington and Alexander. They promoted continuing education for optometrists to further their knowledge of how vision impacts performance. Vision therapy is differentiated between strabismic/orthoptic vision therapy (which many Optometrists, Orthoptists and Ophthalmologists practice) and non-strabismic vision therapy.[38] A.M. Skeffington was an American optometrist known to some as "the father of behavioral optometry".[39] Skeffington has been credited as co-founding the Optometric Extension Program with E.B. Alexander in 1928.[39]

See also

Further reading

Notes and References

  1. Web site: Ophthalmologists express skepticism about vision therapy. 30 Nov 2010. St. Louis Beacon. Jo Seltzer. dead. https://web.archive.org/web/20130720014459/http://stlbeacon.org/#!/content/17515/vision_therapy_part_2. 2013-07-20.
  2. News: Concocting a Cure for Kids With Issues. 10 March 2010. Judith Warner. The New York Times.
  3. Book: Pseudoscience in Child and Adolescent Psychotherapy: A Skeptical Field Guide . Hupp S . Chapter 5: Learning . LaBrot Z, Dufrene B . 66–79 . 2019 . Cambridge University Press . 9781107175310 . 10.1017/9781316798096.007. 240819473 .
  4. Web site: Vision Therapy Quackery . Novella S . . 31 January 2018 .
  5. Whitecross S . Vision therapy: are you kidding me? Problems with current studies . Am Orthopt J . 63 . 36–40 . 2013 . 24260807 . 10.3368/aoj.63.1.36 . 9835985 . Review .
  6. Rucker JC, Phillips PH . Efferent Vision Therapy . J Neuroophthalmol . 38 . 2 . 230–236 . June 2018 . 28059865 . 10.1097/WNO.0000000000000480 . 11582050 .
  7. 15825744 . 2005 . Rawstron . J. A . A systematic review of the applicability and efficacy of eye exercises . Journal of Pediatric Ophthalmology and Strabismus . 42 . 2 . 82–8 . Burley . C. D . Elder . M. J . 10.3928/01913913-20050301-02 .
  8. Web site: AAPOS is the American Association for Pediatric Ophthalmology and Strabismus . Scott C . 17 December 2020 . Vision Therapy .
  9. 10.1111/j.1475-1313.2008.00607.x . 19154276 . A critical evaluation of the evidence supporting the practice of behavioural vision therapy . Ophthalmic and Physiological Optics . 29 . 1 . 4–25 . 2009 . Barrett . Brendan T . free .
  10. Barton J, Ranalli P . Vision Therapy: Ocular Motor Training in Mild Traumatic Brain Injury . Annals of Neurology . 88 . 3 . 453–461 . June 2020 . 10.1002/ana.25820. 32542907. 219706486 .
  11. Web site: Orthoptist . 8 May 2014.
  12. American Academy of Ophthalmology. Complementary Therapy Assessment: Vision Therapy for Learning Disabilities. Retrieved August 2, 2006.
  13. International Orthoptic Association document "professional role"
  14. West . S . Williams . C . Amblyopia. . BMJ Clinical Evidence . 30 June 2011 . 2011 . 21714945 . 3275294.
  15. Web site: TCOS.ca :: The Canadian Orthoptic Society. dead . https://web.archive.org/web/20040501142128/http://www.tcos.ca/about_orthoptics.html . 2004-05-01 .
  16. Vukicevic, M., Koklanis, K and Giribaldi, M. Orthoptics: Evolving to meet the increasing demand for eye service. In Insight news. March 2013: Sydney, Australia.
  17. News: Concocting a Cure for Kids With Issues . NY Times . March 10, 2010 . 9 May 2014 . JUDITH WARNER.
  18. Web site: The Stages of Change . Virginia Polytechnic Institute and State University . 8 May 2014.
  19. Web site: Eye Tracking And Prompts For Improved Learning . Worcester Polytechnic Institute . 8 May 2014.
  20. Vision, learning and dyslexia. A joint organizational policy statement of the American Academy of Optometry and the American Optometric Association . Journal of the American Optometric Association . 68 . 5 . 284–6 . 1997 . 9170793 .
  21. Web site: Convergence Insufficiency Treatment & Management . Medscape . 8 May 2014 . Michael J Bartiss.
  22. Web site: Eye Muscle Problems in Children and Adults: A Guide to Understanding . Burton J. Kushner . 2014.
  23. Web site: Cawthorne-Cooksey Exercises for Dizziness . Dizziness-and-balance.com . 2013-02-15.
  24. Zhang KK . Koklanis K . Georgievski Z . 2007 . Intermittent exotropia: A review of the natural history and non-surgical treatment outcomes . Australian Orthoptic Journal . 39 . 1. 31–37 .
  25. Web site: Eye-Related Quackery . 6 July 2018 . Quackwatch . Russell . Worrall. Nevyas, Jacob . Barrett, Stephen .
  26. Web site: Do eye exercises improve vision? . March 2021 . AllAboutVision.com . Gary . Heiting . 20 March 2021 .
  27. 10.1055/s-2002-32883 . Bessern Prismen nach Hans-Joachim Haase die Stereosehschärfe? . Do prisms according to Hans-Joachim Haase improve stereoacuity? . de . Klinische Monatsblätter für Augenheilkunde . 219 . 6 . 422–8 . 2002 . Kromeier . Miriam . Schmitt . Christina . Bach . Michael . Kommerell . Guntram . 12136437. 72028637 .
  28. 10.1055/s-2006-927268 . Beeinflussen Prismen nach H.-J. Haase die Augenprävalenz? . Do Prism Corrections According to H.-J. Haase Affect Ocular prevalence? . de . Klinische Monatsblätter für Augenheilkunde . 224 . 1 . 32–9 . 2007 . Schroth . V . Jaschinski . W . 17260317. 260203639 .
  29. 11840793 . 2002 . Kommerell . G . Prism correction in heterophoria . Der Ophthalmologe: Zeitschrift der Deutschen Ophthalmologischen Gesellschaft . 99 . 1 . 3–9 . Kromeier . M . 10.1007/PL00007112 . 9739355 .
  30. 10.1007/bf03163758 . Wie notwendig sind Prismen? Verzicht auf Polatest-induziert fehlapplizierte Prismenbrillen in mehr als 70 Fällen . How necessary are prisms? In more than 70 cases taking away prism which have been wrongly applied based on pola test-procedure only . de . Spektrum der Augenheilkunde . 9 . 2 . 63–73 . 1995 . Brügger . N . Champion . R . Flury-Cornelis . H . Payer . G . Payer . H . Siegenthaler . B . Starkermann . M . Weisstanner . B . 24248991 .
  31. Web site: Science-Based Medicine . A Science Lesson from a Homeopath and Behavioral Optometrist . 1 March 2015 . Novella, Steven . Steven Novella . 28 October 2009.
  32. Jennings . 2000 . Behavioural optometry – a critical review . . 1 . 67.
  33. Wolraich et al. 2008, pp. 269-270.
  34. https://www.aoa.org/optometrists/membership/aoa-sections/sports-vision-section "Sports & Performance Vision: Tools for expanding your practice and reaching new patients."
  35. Erickson, Graham (2007). Sports Vision. Butterworth-Heinneman.
  36. Helveston. Eugene M. 2005. Visual Training: Current Status in Ophthalmology. American Journal of Ophthalmology. 140. 5. 903–10. 10.1016/j.ajo.2005.06.003. 16310470.
  37. Georgievski. Zoran. Koklanis. Konstandina. Fenton. Adam. Koukouras. Ignatios. 2007. Victorian orthoptists' performance in the photo evaluation of diabetic retinopathy. Clinical & Experimental Ophthalmology. 35. 8. 733–8. 10.1111/j.1442-9071.2007.01576.x. 17997777. 8661627.
  38. 8014367 . 1994 . Birnbaum . M. H . Behavioral optometry: A historical perspective . Journal of the American Optometric Association . 65 . 4 . 255–64 .
  39. http://legacy.revoptom.com/archive/resource/visionaries.htm#skeffington "A.M. Skeffington, O.D.: The Father of Behavioral Optometry."