Amblyopia

Lazy eye (amblyopia) is reduced vision in one eye caused by abnormal visual development early in life. The weaker — or lazy — eye often wanders inward or outward. Amblyopia generally develops from birth up to age 7 years. It is the leading cause of decreased vision among children. Rarely, lazy eye affects both eyes. Early diagnosis and treatment can help prevent long-term problems with your child's vision. The eye with poorer vision can usually be corrected with glasses or contact lenses, or patching therapy.

Signs and symptoms of lazy eye include: An eye that wanders inward or outward. Eyes that appear to not work together. Poor depth perception. Squinting or shutting an eye. Head tilting. Abnormal results of vision screening tests.

Amblyopia occurs when there is a major difference between the two eyes in their ability to focus. The most common cause of amblyopia is other vision problems. It’s important to treat these other conditions, or the brain starts relying on the eye with better vision, leading to amblyopia. Common causes of the condition include: Muscle imbalance (strabismus amblyopia). The most common cause of lazy eye is an imbalance in the muscles that position the eyes. This imbalance can cause the eyes to cross in or turn out, and prevents them from working together.

In the VIP Study, demographic information (birth date, gender, race and ethnicity) of a child was collected at enrollment based on information provided by the child’s parent or legal guardian. For easier comparison with other studies Race/ethnicity was classified as American Indian, Asian, Black, non-Hispanic White, Hispanic, and other/unknown (for those reported with more than one race categories or those without race information). Age was calculated as the difference between date of comprehensive eye examination and birth date, and was grouped as 36–47 months, 48–59 months, and 60–72 months. Ocular risk factors were defined based on findings from comprehensive eye examinations. Strabismus status was classified as esotropia, exotropia, or no horizontal strabismus. To facilitate comparison of our findings with those from other studies, we defined the presence and severity level of the ocular risk factors similarly to other studies.6,14 For the ocular risk factors of unilateral amblyopia, we determined each type of refractive error based on the worse eye, as we assumed that the ocular condition in the worse eye dominated the association with unilateral amblyopia. We classified presence and severity levels for myopia (<0.5 D, ≥0.5 to <2 D, ≥2 D), hyperopia (<2 D, ≥2 to <3 D, ≥3 to <4 D, ≥4 to <5 D, ≥5 to <6 D, ≥6 D), astigmatism (<1 D, ≥1 to <2 D, ≥2 to <3 D, ≥3 to <4 D, ≥4 D), and spherical equivalent anisometropia (<0.5 D, ≥0.5 to <1 D, ≥1 to <2 D, ≥2 D). For the ocular risk factors of bilateral amblyopia, we defined bilateral astigmatism and bilateral hyperopia based on the better eye. Because bilateral amblyopia is a condition affecting both eyes, we required that both eyes should have the refractive error to qualify it as an ocular risk factor for bilateral amblyopia.

Certain complications can occur with amblyopia, including: Blindness: If untreated, the person may eventually lose vision in the affected eye. This vision loss is usually permanent.

You can't prevent amblyopia or the other vision problems that may cause it. But you can stop it from getting worse or causing permanent problems. The best way to prevent vision loss from amblyopia is to get regular eye exams. Make sure your child has a thorough eye exam by the age of 6 months and then again by 3 years.