Amblyopia vs. Strabismus: Understanding the Differences

Amblyopia and Strabismus are treatable eye disorders due to poor development of the eye.

Many people lose their vision because they need to understand different eye problem terms or consult their ophthalmologist early enough. It can be even more confusing for patients with amblyopia or Strabismus because they share similar characteristics. Both conditions are functional vision problems that require customized treatments. Not even prescription glasses can correct amblyopia conditions.

Although Strabismus and amblyopia share many characteristics, they are two different eye conditions that may affect anybody. Strabismus is very common among infants and young children. Statistics show that Strabismus affects 2-4% of adults and children. It’s a condition that occurs when one or both eyes are not aligned properly. Unlike many other eye conditions, Strabismus makes your eyes look in different directions.

What’s Amblyopia?

Amblyopia occurs when there is poor development of your vision. Also known as the lazy eye, this condition occurs when the sight in one eye is compromised. Amblyopia develops when the eye and the brain don’t coordinate properly. It’s a disorder that prevents one or both eyes from achieving normal visual acuity.

Amblyopia usually develops due to Strabismus or communication breakdown between the eye and the brain. The brain fails to recognize the sight from a weak eye and eventually relies on the other stronger eye for better communication. Over-reliance on the stronger eye makes vision on the weaker eye even worse, hence the name “lazy eye.”

You are likely to see blurred images if you have a lazy eye. While the stronger eye has clear images, the lazy eye develops a blurred image because the brain focuses only on the clear one. The larger the angle of the Strabismus, the more likely the brain will forget the affected eye. Therefore, the brain suppresses information and ignores all visual signals from the weaker eye.

Strabismus

Strabismus affects both eyes. It’s a condition that makes your eyes look at different locations simultaneously. Strabismus is the most common cause of amblyopia and can easily be confused with lazy eyes. Also known as the crossed eye, this condition develops due to misalignment in one or both eyes. Lack of alignment results in the eyes turning inward, compromising your vision.

Misalignment may happen recurrently, and the condition usually has severe vision problems. Strabismus is more common in infants and young children. Older children above three years and adults can also get Strabismus, though it’s rare. Usually, amblyopia accompanies Strabismus, but it can also occur without Strabismus.

This article will discuss the differences between these two conditions.

Differences between Strabismus and amblyopia

Even though there are many differences between these two conditions, a vision therapy specialist can treat them.

Strabismus occurs when the eyes fail to point at the same place simultaneously. One or both eyes may turn inward, upward, or outward recurrently or constantly. Amblyopia, however, is a condition that develops when there is a lack of clear vision.

Types of Strabismus and amblyopia

There are three types of amblyopia which all result from suppression of vision in one or both eyes. You can differentiate these three types of amblyopia by finding the root cause of the suppression.

We have the following types of amblyopia:

Refractive amblyopia
Strabismic amblyopia
Deprivation amblyopia

The types of Strabismus are, however, determined by various factors, which include:

Frequency of the eye turn
The direction of the eye turn
Which eye turns

There are many types of Strabismus which can be grouped into the following broad categories:

Esotropias: One of your eyes turns towards your nose, making it difficult for both eyes to focus in the same direction.
Exotropias: This condition causes the eye to turn outwards
Hypertropias and hypotropias: One eye is higher (hypertropia) or lower (hypotropia) than the fellow eye.

Strabismus affects 4% of the population, while amblyopia is more common, affecting 4 -6%.

Causes of amblyopia and Strabismus

You can develop Strabismus later in life or be born with it. Some accidents can also occasion strabismus condition. There are underlying health conditions that might also cause Strabismus. For instance, genetics puts you at a higher risk of getting Strabismus. If your parents had the disorder, you would likely develop any types of Strabismus discussed above.

Strabismus occurs when neurological problems interfere with the eyes’ control and function. These neurological problems might originate in the eye muscles, nerves, or vision centers within the brain. Most strabismus problems or conditions occur due to compromised communication between the eyes and the brain.

Amblyopia is more common in infants; it begins during infancy and early childhood. Some of the most common types of amblyopia include:

Blockage of the eye due to trauma
Constant turn of the eye
Numerous prescriptions in each eye

The leading cause of amblyopia, however, remains Strabismus.

What are the symptoms?

One of Strabismus’s most common symptoms is an easily noticeable eye turn. Most patients with constant Strabismus are less symptomatic when compared to patients with intermittent Strabismus.

If you have recurrent Strabismus, you may experience the following symptoms:

Blurry vision
Constant headaches
Eye strain and sometimes pain

Amblyopia is very difficult to spot. The signs aren’t visible, and it may take quite a while to notice changes in your eyes. Some of the symptoms that may point to a possible case of amblyopia include:

Difficulty in determining the depth of a surface
Fatigue with close work
Head turn or tilt
Clumsiness
Eye strain

If you have a child, be more concerned if they cry or protest whenever you cover one eye. That could be a sign of amblyopia.

Takeaway

Amblyopia doesn’t go away unless treated. Treating this condition early in life is essential to avoid permanent visual problems. Some patients might need strong prescription glasses to improve amblyopia. Glass prescription may not fully address the disorder, but it help with the symptoms.

An ophthalmologist may treat some forms of Strabismus with a surgical procedure. However, surgery doesn’t treat the underlying cause of Strabismus or improve your visual acuity.