What is Amblyopia?
Amblyopia, often called a lazy eye, is a condition in which the vision in one or both eyes cannot be corrected to 20/20 despite wearing the correct eyeglasses or contact lenses. This leads to a lack of development or deterioration of the vision in the eye that is not being used.
Amblyopia is the most common cause of visual impairment in children. Amblyopia can be caused by strabismus (an eye turn), by unequal lens prescriptions between the two eyes, or high lens prescription in both eyes that was previously uncorrected. The tests required to fully diagnose the cause and type of amblyopia are often not included in traditional vision screenings.
What are symptoms of Amblyopia?
People with amblyopia experience one or more of the following symptoms:
- Blurry vision (reduced visual acuity)
- Difficulty with depth perception
- Difficulty reading
- Eye tracking issues
- Eye fatigue/tired eyes
- Difficulty with visual tasks (such as driving or reading)
- Poor eye-hand coordination
If you or a loved one experience any of the above symptoms, a Neuro-Vision Evaluation conducted by a Neuro Optometrist is the only means of getting a clear and accurate diagnosis. If you’re interested in better understanding the seriousness and severity of the symptoms you or a loved one are experiencing, we encourage you to take our Vision Symptom Quiz.
What causes Amblyopia?
An amblyopic eye, commonly called lazy eye, is not really lazy. Recent research has shown that amblyopia occurs because of a reduced ability in how the eyes work together as a team, therefore it is actually a binocular vision disorder. Amblyopia is an active process due the brain actively suppressing or shutting off the information coming from one eye, so the eye develops blurry vision.
Amblyopia occurs when vision is disrupted in one eye or both eyes. Amblyopia can be caused by strabismus (an eye turn), uncorrected glasses prescription in one eye (that is usually higher than the other eye), uncorrected glasses prescription in both eyes, or visual disruption in the eye due to cataracts or a dropping of the eyelid. Individuals with far-sightedness are more likely to develop amblyopia.
How is Amblyopia treated?
Vision therapy works to equalize the vision in both eyes by enhancing vision in the amblyopic eye and improving binocular vision for use of both eyes to accurately team together, treating the root cause of the problem. This is in contrast to the frequent eye patching that is commonly prescribed. While eye patching can help develop clearer vision initially, typically this does not provide lasting results since the underlying cause of how both eyes are working together is not addressed. It is important to treat this condition as a binocular vision condition through a progressive neuro-vision therapy program, which provides long-term improvements in clarity and depth perception. Amblyopia can be treated at any age.
Our philosophy of treating amblyopia is to treat the underlying root cause, which is working on the brain’s ability to process both eyes together accurately as a team. Please click here to read “Treating amblyopia without the patch” that describes our philosophy of amblyopia treatment.
By Dan L. Fortenbacher, O.D., FCOVD. Amblyopia Treatment – Eye Patching Alone is No Longer the Standard of Care.
The best approach for the treatment of amblyopia involves a combination of monocular and binocular training of the visual brain through office-based vision therapy. This is done with a vision therapist under the direct supervision of a Doctor of Optometry along with prescribed home-oriented visual activities to complement the weekly or bi-weekly in-office procedures.
Hess RF, Thompson B. Amblyopia and the binocular approach to its therapy. Vision Res. 2015;114:4-16.
Conclusion: Patching therapy has been used to treat amblyopia for hundreds of years even though its shortcomings are many. Although 79% of children show at least a 2 line improvement after 4 months of patching (Repka et al., 2003), 25% of these children will regress to some degree once the patch is removed (Holmes et al., 2004).
A number of hybrid binocular approaches have been suggested, which are all directed to recovering monocular function but rather than doing this under monocular conditions they do it under binocular viewing. The aim is to involve the fixing eye in recovery of vision through intensive training/detection of targets presented exclusively to the amblyopic eye.
Gunton, KB. Advances in Amblyopia: What Have We Learned From PEDIG Trials? Pediatrics March 2013, 131 (3) 540-547.
Conclusion: Amblyopia is the most common cause of preventable visual loss in children. This article reviews treatment options, durations, and efficacy in randomized multicenter trials conducted by the Pediatric Eye Disease and Investigator Group in the last decade. Parents and patients should be counseled that many forms of treatment are efficacious, allowing the option of choice of best-tolerated treatment method. Compliance is key to successful treatment. The course of treatment is likely at least 6–12 months, with yearly follow-up suggested once amblyopia has been treated to monitor for regression.
Managing Amblyopia: Can Vision Therapy Cut It? By Kara Tison, OD, and Amanda Nicklas, OD
Published October 15, 2017.
Conclusion: While traditional treatment for amblyopia improves monocular function by providing visual input to the amblyopic eye, vision therapy can assist in treating the underlying binocular dysfunction that accompanies amblyopia. By initiating vision therapy, the doctor can reduce the total amount of therapy time necessary. Additionally, adding vision therapy to patching is considered to be more effective than patching alone.
Frantz KA. Rationale for refractive correction, occlusion and active vision therapy for amblyopia treatment. J Behavioral Optom. 1995;6(1):14, 18-19.
Rouse MW, Cooper JS, Cotter SA, et al. Optometric clinical practice guideline: care of the patient with amblyopia. American Optometric Association. 1994.
Wick B, Wingard M, Cotter S, Scheiman M. Anisometropic amblyopia: is the patient ever too old to treat? Optom Vis Sci. 1992;69(11):866-78.
Flax N. Some thoughts on the clinical management of amblyopia. Am J Optom Physiol Opt. 1983;60(6):450-3.