Refractive amblyopia is the most common type of lazy eye. It occurs most commonly when a child is born with a high refractive error (diminished acuity or blurriness) in one eye, despite having perfectly aligned eyes. For example, one eye may have significant nearsightedness or farsightedness, while the other eye does not. Or one eye may have significant astigmatism and the other eye does not.
So what is refractive amblyopia? Because one eye has good vision and the other does not, the vision of the child does not develop normally. In such cases, the brain relies on the eye that has less uncorrected refractive error (better acuity) and "tunes out" the blurred vision (this is called suppression) from the other eye, causing amblyopia in that eye from disuse.
It is important to note that a young child with amblyopia rarely expresses any symptoms or knows that what they are experiencing isn't normal. Refractive amblyopia cannot be seen -- it is not the same as strabismic amblyopia which often times can be seen due to a misalignment of the eyes. Amblyopia must be diagnosed by an eye care professional and early intervention is important. It is the most common eye problem among children and left untreated it can cause significant problems and lead to vision loss.
People with refractive amblyopia will have poor binocular vision skills to varying degrees. This can cause difficulty with things like driving and parking a car, difficulty with reading and learning, and more. They may seem clumsy or uncoordinated. Patients have reported trouble with things like riding a bike, navigating a room full of people, seeing in 3D, participating in sports, etc.
Improvements are possible at any age, but early detection and treatment offer the best outcome. Even if no signs or symptoms are noticed, it is important that children are taken to an optometrist for a comprehensive visual assessment during the first year of life to help catch problems like refractive amblyopia at an early stage.
Treatment of refractive amblyopia can include vision therapy, eye patching, eye drops, refractive surgery, or a combination of those options. Vision therapy may include the use of virtual reality technology in treatment of lazy eye. It is also common for patients with refractive amblyopia to wear prescription lenses or contact lenses as a form of or as part of their treatment.
Eye patching is a time-tested treatment for amblyopia. It is low-risk and relatively low-cost. Kids often dread wearing it, and parents can have trouble forcing and monitoring their children to keep the patch on; however, it has improved the vision of millions of patients with lazy eye for the last thousand years.
Eye patching should typically be tried before or alongside other treatments like vision therapy and Vivid Vision. Eye patching doesn't work for everyone, particularly adults, and the amblyopia often regresses. Binocular visual experience is necessary in successful treatment of amblyopia and strabismus, and this experience is not provided during eye patching. Most cases require something more targeted and comprehensive such as vision therapy and/or Vivid Vision.
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