A lazy eye can be an easy diagnosis to spot. Most of the time, when I walk into an exam room, I detect if a child has a lazy eye even before I sit down. I make eye contact with the child when I walk into the room, the child looks at me, and I notice that the eyes don’t track correctly. The surprising thing to me is how often parents are surprised when I bring it up.

So what is a lazy eye? The medical term for lazy eye is amblyopia. By definition, amblyopia is an eye condition that causes decreased vision that is a result of abnormal visual development. It usually affects one eye, but can affect both eyes. Lazy eye happens if the nerve pathways between the brain and the eye aren’t stimulated like they are supposed to. Consequently, the brain starts to favor the eye with better vision. The other, weaker eye tends to wander and eventually the brain ignores signals from the weak eye and it gets lazy.

Signs and symptoms of lazy eye

1. One (or both) of the eyes wander inward or outward. (Tip: If you aren’t sure, take a picture of your kid. There will be a small light reflection seen in the colored portion of the eyes. Is the reflection in the same place in both eyes? If no, you may have a problem).
2. Eyes that may not appear to track or work together.
3. Poor depth perception.

Causes of lazy eye

1. Strabismus: The muscles that move the eye are not equally balanced and can cause the eyes to cross or turn out.
2. Deprivation: If something “deprives” the eye of clear vision (e.g., a cataract or cloudy area in the lens).
3. Refractive error: If there is a significant vision difference between the two eyes (e.g., severe nearsightedness, farsightedness, or astigmatism).
4. Crazy/rare stuff: I hesitate to even mention these reasons (because a worried parent will focus on the worst case scenario, but I need to include them for accuracy/completions sake). These are things like eye tumors or inner eye problems. I repeat, these are super rare.

Treatment for lazy eye

As a general rule, the earlier it is treated, the better the outcomes (because this is when the connections between the brain and eye are still forming). How lazy eye is treated depends on the cause.

1. Glasses or contacts. These are used if the problem is nearsightedness, farsightedness, or astigmatism.
2. Eye patches. Still used today, but less often. The idea is to strengthen the weaker eye.
3. Eye drops (usually Atropine). The drop is used in place of a patch. It blurs the vision in the good eye, thereby hoping to improve the weaker eye. Generally utilized as a last resort if uneven eye muscles are the problem.

Age Exceptions

Do not read this and stress if your child is a newborn. The general rule of thumb is that it takes a little while for the eyes to mature/improve enough to track properly. So if your child is sub 2 months (in some cases up to 4 months is normal), it’s too early to worry.

Lazy eyes often run in families and are more common in children that were born premature. If it is missed or not treated it can cause permanent vision loss. So if you suspect it, make sure you get it checked out by a professional.