Vision Therapy

Cathy Chang

What is Vision Therapy?What is Vision Therapy?

Vision therapy (visual training, vision training) is an individualized supervised treatment program designed to correct visual-motor and/or perceptual-cognitive deficiencies

Why Vision Therapy?Why Vision Therapy? Behavioral Optometrists believe that vision

is a learned skill; Vision plays the largest role in learning.

“There's more to vision than just having 20/20 eyesight.  A strong visual system is needed for reading, using a computer, and playing sports.”

Vision Related Learning ProblemsVision Related Learning Problems

Physical Symptoms

• Jerky eye movements, one eye turning in or out• Squinting, eye rubbing, or excessive blinking• Blurred or double vision• Headaches, dizziness, or nausea after reading• Head tilting, closing or blocking one eye whenreading

Secondary Symptoms

• Smart in everything but school• Low self-esteem, poor self image• Temper flare ups, aggressiveness• Frequent crying• Short attention span• Fatigue, frustration, stress• Irritability• Day dreaming

Vision Related Learning ProblemsVision Related Learning Problems

Performance Clues

• Avoidance of near work• Frequent loss of place• Omits, inserts, or rereads letters/words• Confuses similar looking words• Failure to recognize the same word in the next sentence• Poor reading comprehension• Difficulty copying from the chalkboard• Book held too close to the eyes• Inconsistent or poor sports performance

Social Labels

• Lazy• Dyslexic• Attention Deficit Disorder• Slow learner• Behavioral problems• Working below potential

Amblyopia (lazy eye)Amblyopia (lazy eye) A condition in

which one eye has reduced vision; There’s a difference in visual acuity between the two eyes

Normal Vision Lazy Eye Vision

CausesCauses An obstruction of vision within one eye due to

injury or disease Significant differences between the clearness

of the images seen by each eye due to farsightedness, nearsightedness or astigmatism

Misaligned eyes or crossed eyes (strabismus)

Clinical SymptomsClinical Symptoms Frequent squinting or closing one eye to see,

poor visual acuity, eyestrain, headaches Lack of brain stimulation from the weaker eye

causes the strong eye to become dominant. The amblyopic eye is suppressed and may even become blind.

While an amblyopic eye may look normal, it is not being used normally.

Early DiagnosisEarly Diagnosis Amblyopia can be prevented through early diagnosis and

treatment. Without treatment, an amblyopic eye may never develop properly, and even become blind. Some vision loss can be restored if the diagnosis is early enough, usually before age 5. This early treatment is necessary because an amblyopic eye has problems in its connections with the brain, rather than in and of itself.

Often, it is first necessary to treat the underlying cause of amblyopia before strengthening the child’s weaker eye.

Treatment OptionsTreatment Options Wearing eyeglasses or contact lenses to align or focus

the eyes Wearing a patch on the stronger eye for weeks or

months, which forces the amblyopic eye to work, developing more connections with the brain.

Surgery on the eye muscles A program of Vision Therapy to help equalize vision in

both eyes, improve eye coordination, and restore clear single vision.

Strabismus (crossed eyes)Strabismus (crossed eyes)

the inability to point both eyes in the same direction at the same time.

CausesCauses Inadequate development of eye coordination in

childhood Excessive farsightedness (hyperopia) or

differences between the vision in each eye Problems with the eye muscles that control eye

movement Head trauma, stroke, or other general health

problems.

SymptomsSymptoms One eye may appear to turn in (estropia), out (extropia),

up (hypertropia), or down (hypotropia). The eye turn may occur constantly or only occasionally

(intermittent). Eye-turning may change from one eye to the other

(alternating). Eye-turning may only appear when a person is tired or

has done a lot of reading. Double vision may occur. To avoid seeing double, vision in one eye may be

ignored resulting in a lazy eye (amblyopia).

TreatmentTreatment

Eyeglasses Vision Therapy Eye muscle surgery.

VT Approach & TechniquesVT Approach & Techniques

Best Diagnostic Approach: Combined Programs and Homework Therapy Sessions include: Home Checks, Diagnosis, Tutoring, 30

minute sessions each

Therapeutic lenses (regulated medical devices) Prisms (regulated medical devices) Filters Occluders or patches Electronic targets with timing mechanisms Computer software Balance boards

VT Approach & TechniquesVT Approach & Techniques Monocular activities designed to equalize the focusing, tracking and

pointing of each eye. Binocular work to improve eye-teaming efficiency. Visual-spatial tasks to develop integrated sequential and directional

concepts. Form training stressing: visual discrimination, spatial relationships,

form constancy, figure/ground relationships and visual closure. A visualization program to improve the speed and span of visual

recognition as they pertain to short and long-term visual memory. Visuo-motor tasks to improve body awareness and control, and

visually directed fine motor skills. Inter-sensory integration skills through visualauditory-verbal

matching.

DemonstrationsDemonstrations

Pencil Tracking, Ball Tracking Blocks Eye Patches Prisms Visual-motor Task Body Balance Paper Tearing

Research StudiesResearch Studies Binocular Dysfunctions BACKGROUND: Although vision therapy has reportedly been very successful in

elimination of asthenopic symptoms (excessive tearing, itching, burning, visual fatigue, and headache) in adults with convergence insufficiency, controlled studies have not been performed, and a clinical bias exists against prescribing vision therapy for adults with convergence insufficiency. METHODS: Sixty adult males over the age of 40 years (median age, 65 years) with convergence insufficiency were divided into three treatment groups: office-based vision therapy with supplementary home therapy, home therapy only, and a control group. RESULTS: Vision therapy was successful in 61.9% of patients who received in-office plus home therapy, in 30% of patients who received home therapy only, and in 10.5% of the control group. The success rate for patients who received active in-office vision therapy supplemented with home procedures was significantly greater than that for controls. Home therapy alone was less successful than in-office therapy. The success rate obtained with home therapy alone was not significantly greater than that demonstrated by controls. CONCLUSIONS: Vision therapy is effective in eliminating asthenopia (eyestrain) and improving convergence function in adult patients. In-office therapy combined with home therapy tends to produce better results than does home therapy alone. (Birnbaum MH, Soden R, Cohen AH. Efficacy of vision therapy for convergence insufficiency in an adult male population. Journal of the American Optometric Association, April; 70(4): 225-232, 1999.)

Research StudiesResearch Studies Amblyopia

BACKGROUND: The pediatric clinic of the SUNY State College of Optometry/University Optometric Center (New York) develops a yearly quality management plan to monitor patient care. One of the areas retrospectively reviewed for all outcomes is refractive amblyopia. METHODS: A retrospective review of records was performed on patients diagnosed with refractive amblyopia. With the use of a prescribed protocol, each patient's progress was tracked for a period of 6 months. Major emphasis was placed on outcome as related to treatment modality. Treatment alternatives were optical correction alone, optical correction in conjunction with patching, and optical correction and patching with vision therapy. RESULTS: Improvement criteria included a 2-line increase in visual acuity on the Snellen chart and an increase of 20 seconds of arc of stereopsis, as measured by the Wirt circles. The groups that patched with correction and those that received vision therapy had similar visual acuity improvement's; however, the latter group had a significantly greater improvement in stereopsis. Both groups performed significantly better in both categories when compared to the group receiving optical correction alone. CONCLUSIONS: Though patching alone may be sufficient for improvement of visual acuity, binocular performance is significantly better when vision therapy is included in the treatment regimen. (Krumholtz I, FitzGerald D. Efficacy of treatment modalities in refractive amblyopia. Journal of the  American Optometric Association, June; 70(6): 399-404, 1999.)

Research StudiesResearch Studies Strabismus

BACKGROUND: Occasionally, co-management involving both optometry and ophthalmology is needed to optimize treatment outcome for the strabismic patient. METHODS: JB, a 47-month-old consecutive esotrope presented to our clinic (Southern California College of Optometry). Two previous attempts to surgically correct her exotropia had failed and the parents sought another treatment approach. We recommended optometric vision therapy (VT) to improve sensorimotor fusion before any further surgery. After 31 VT sessions (bi-weekly for a time, then weekly), before a third scheduled surgery, sensorimotor fusion was good in the amblyoscope, but unstable with neutralizing prism in free-space. We recommended surgery be postponed, but the family proceeded. Esotropia recurred with constant suppression. After additional VT, JB developed stable sensorimotor fusion and random dot stereopsis in free-space with neutralizing prism. A fourth surgery was then performed resulting in esophoria at all distances with good sensory fusion. RESULTS: Twenty-one months postoperatively, JB remains nonstrabismic with good sensory fusion. CONCLUSIONS: Clinicians should understand the roles and limitations of available treatment options. Surgery reduces the magnitude of the deviation, whereas optometric VT (vision therapy) provides the unique role of establishing normal sensory processing. (Garriott RS, Heyman CL, Rouse MW. Role of optometric vision therapy for surgically treated strabismus patients. Optometry and Vision Science, April;74(4): 179-184, 1997.)

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therapy.com/About_Vision.htm> “Vision Related Learning Programs” Insight Vision Center

<http://www.insightvision.org/vrlearningprograms.html> “What is Vision Therapy?” College of Optometrists in Vision Development

<http://www.covd.org/od/vt_whatis.html> “Unite for Sight Amblyopia Module” Unite for Sight

<http://www.uniteforsight.org/course/amblyopia.php> “Strabismus/Crossed Eyes” COVD <http://www.covd.org/od/strabismus.html> “Strabismus – What is it?” Optometrists Network <http://www.strabismus.org/> “Introduction to Vision & Brain Injury” NORA

<http://www.nora.cc/patient_area/vision_and_brain_injury.html> “Research Studies & Vision Therapy” Vision-Therapy <http://www.vision-

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