Amblyopia, also known as a “lazy eye,” is described as reduced vision in one eye compared to the other. There are also some rare forms of amblyopia that involve both eyes. Amblyopia is the most common cause of partial or total blindness in one eye in children.
The term lazy eye is misleading: the eye is not actually lazy. In fact, lazy eye is a developmental problem in the nerve connecting the eye to the brain, affecting the brain’s ability to use both eyes together. It is not a problem in the eye itself, but in the brain, which actively ignores the visual input from the misaligned eye, leading to amblyopia in that eye.
In addition to poor visual acuity, people with amblyopia are more prone to having difficulties with depth perception, eye movements related to reading, and visual decision-making while driving.
Amblyopia can develop in childhood due to:
Significant differences in the prescription (refractive) status between the two eyes due to nearsightedness, farsightedness, or astigmatism
Constantly misaligned eyes or crossed eyes (strabismus)
Obstructed vision in early childhood, such as cataract or ptosis (droopy eyelid)
It is important to note that because amblyopia is typically a problem of infant vision development, symptoms of the condition can be challenging to detect. Symptoms may include noticeably favoring one eye over the other, an eye turn (either upward-downward outward or inward), or a tendency to bump into objects on one side.
Comprehensive eye examinations are the best way to identify children who are at risk for or already have amblyopia.
Amblyopia can be treatable at any age, although the earlier the problem is found and treated, the more successful the outcomes tend to be.
Many children who have anisometropia, or unequal vision, do not know they have an eye problem because the stronger eye and the brain compensate for the difference. Over time, the weaker eye gets progressively worse, and amblyopia develops.
Glasses can correct nearsightedness, farsightedness, or astigmatism, any of which can cause amblyopia. They may also correct an eye turn. Sometimes, glasses solve the amblyopia, and no further treatment is required.
If a cataract is the cause of amblyopia, it can be removed surgically under either local or general anesthesia.
In some cases, amblyopia is caused by an eyelid blocking the vision in the weaker eye; in such cases, the usual treatment is surgery to lift the eyelid. Once the blockage is corrected and any underlying medical issues are treated, then your doctor can explore additional ways to help improve vision, if needed.
To correct amblyopia, better-seeing patients may use an eye patch for several hours each day or all day long. This treatment may continue for weeks or months. The patient should be encouraged to do close-up activities while wearing the patch, such as schoolwork, reading, or coloring. Patches come in colorful and fun patterns to help the child accept them.
Your doctor may prescribe atropine eye drops to blur vision in the unaffected eye. Atropine is usually less awkward for children than a patch and can be just as effective. Children who cannot tolerate wearing a patch may be prescribed eye drops instead.
Children may be prescribed exercises and games to improve vision development in the affected eye, sometimes in combination with other treatments.
Surgery can improve the appearance of an eye turn, resulting in better alignment of the eyes. It may or may not improve vision.
Amblyopia often starts before there are any obvious signs that something is wrong. Regular eye examinations in babies and young children can help catch amblyopia before it becomes noticeable to the casual observer. According to research, children should have eye examinations at the following times:
Before the child is 3 months old
Between 6 months and 1 year of age
At 3 years of age
At 5 years of age
If there are any concerns that the child may be suffering from or developing a “lazy eye,” have the child examined right away. Children with a family history of amblyopia are at a higher risk of developing it themselves.
Early diagnosis and treatment increase the chance of a complete recovery. Amblyopia will not go away on its own. If amblyopia is not diagnosed until the preteen, teen, or adult years, treatment will take longer and is often less effective. The sooner the treatment begins, the better.