top of page

The Hidden Symptoms of Anisometropia

Updated: Dec 12, 2023

What You Need to Know about Anisometropia

Good vision is something many of us take for granted until it starts to deteriorate. Anisometropia is one of a condition that can have a significant impact on visual health. You might not have heard of it, as it’s not as famous as near sightedness or astigmatism, but it can still mess with your vision. This blog post will discuss the symptoms of anisometropia, uncovering the hidden challenges it can bring and explaining what you should know to deal with it.

Jump to:

What is Anisometropia?

Anisometropia occurs when one eye’s vision is worse than the other due to a significant difference in the refractive errors between the eyes. Refractive error is a mismatch between the eye’s light-focusing power and its length. Refractive errors refer to the way light is bent as it passes through the eye to form an image on the retina. As a result, images on the retina become blurry. The most common types of refractive errors are myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.

In anisometropia, one eye typically has a different degree of refractive error than the other. This means that one eye may be nearsighted while the other is farsighted or that one eye has a higher degree of astigmatism than the other.

Prevalence of Anisometropia

The prevalence of anisometropia varies from around 6% to 14% according to the studies. However, some sources state that anisometropia affects up to 28% of people.

Who is at Most Risk to Develop Anisometropia?

Several factors can contribute to the risk of developing anisometropia. These include genetic predisposition, as individuals with a family history of the condition may be more susceptible.

Additionally, anisometropia is more likely to occur when there are existing refractive errors, such as myopia or astigmatism, especially if one eye’s prescription differs significantly from the other.

Age can also play a role, with anisometropia being more prevalent or noticeable in children and young adults as their eyes are still developing. Certain eye health conditions, like cataracts or corneal irregularities, may lead to anisometropia, particularly when one eye is affected more severely than the other.

Hidden Symptoms of Anisometropia

  1. Blurred or Double Vision: One of the most common hidden anisometropia symptoms is blurred or double vision. Because each eye perceives the world differently due to the difference in refractive errors, the brain struggles to merge the images into a single, clear picture. This can result in seeing double or experiencing a persistent blur, especially when trying to focus on objects at different distances.

  2. Eye Strain and Fatigue: Anisometropia can lead to eye strain and fatigue. The eyes work harder to compensate for the visual discrepancy, which can cause discomfort, headaches, and even difficulty concentrating on tasks that require visual acuity.

  3. Reduced Depth Perception: Depth perception is crucial for activities like judging distances while driving or playing sports. It can impair depth perception, making these activities more challenging and potentially dangerous.

  4. Poor Hand-Eye Coordination: The difference in visual input from each eye can affect hand-eye coordination. This can impact daily activities such as catching a ball, threading a needle, or even pouring a glass of water.

  5. Amblyopia (Lazy Eye): In some cases, anisometropia can lead to amblyopia, commonly known as a “lazy eye.” When one eye is significantly weaker or has a much different prescription than the other, the brain may start to favor the stronger eye, causing the weaker eye’s vision to deteriorate further if left untreated. This condition is also called anisometropic amblyopia.

Types of Anisometropia

Simple Anisometropia

In simple anisometropia, one eye has a refractive error (e.g., myopia, hyperopia, or astigmatism), while the other eye has no refractive error.

For example, one eye may be nearsighted (myopic) with a prescription of -4.00 diopters, while the other eye is emmetropic (no refractive error) or has a much lower myopic prescription.

Compound Anisometropia

Compound anisometropia happens when both eyes have the same vision problem (e.g., nearsightedness), but there is a significant difference in the refractive errors. Therefore, blurry vision appears.

For instance, one eye may be myopic (nearsighted) with a prescription of -4.00 diopters, while the other eye is hyperopic (farsighted) with a prescription of +2.00 diopters. This type of anisometropia can lead to more complex visual issues.

Mixed Anisometropia

Mixed anisometropia involves a combination of different types of refractive errors between the two eyes. For example, one eye may have myopia (nearsightedness), while the other eye has astigmatism. This combination can make it challenging to find appropriate corrective lenses.

Treatment Options

  1. Prescription Glasses or Contact Lenses: Corrective lenses, such as eyeglasses or contact lenses, can help bring both eyes to a similar level of refractive error, improving visual clarity and comfort.

  2. Surgery: In some cases, refractive surgery like LASIK may be considered to correct the refractive error in one or both eyes.

  3. Vision Therapy: If amblyopia is present, patching, atropine eye drops, and using filter glasses may be used to strengthen the weaker eye and encourage its development.

Challenges and Psychological Impact

Over time, the challenges posed by anisometropia can affect an individual’s overall quality of life. It may limit their ability to participate in various activities, impacting both work and leisure.

The possible appearance of visibly different eyes due to varying degrees of refractive error may result in self-consciousness and a negative self-image. It can lead to low self-esteem and social anxiety, especially in children and teenagers.

Furthermore, the condition can have impact on academic and professional performance. Individuals may find it harder to perform well in school or at work.


Anisometropia may not be as well-known as some other eye conditions, but its impact on visual health and overall quality of life can be significant. If you or someone you know is experiencing unexplained visual symptoms like blurred vision, eye strain, or double vision, it’s crucial to schedule an eye exam with an optometrist or ophthalmologist.

Early detection and appropriate treatment can help manage anisometropia and prevent potential long-term complications. Your eyesight is a precious gift, so don’t hesitate to seek professional help to keep it at its best.

Frequently Asked Questions

What is anisometropia?

Anisometropia is a condition where there is a significant difference in the refractive error between the two eyes, which means that each eye has a different prescription for glasses or contact lenses.

What causes anisometropia?

Anisometropia can have various causes, including differences in the size and shape of the eyes, differences in corneal curvature, or variations in the length of the eyeball.

Can anisometropia lead to amblyopia (lazy eye)?

Yes, untreated anisometropia can increase the risk of amblyopia, where the brain begins to favor one eye over the other, leading to reduced vision in the weaker eye.

Can we see if someone has anisometropia?

Identifying anisometropia typically requires a comprehensive eye examination conducted by an eye care professional, such as an optometrist or ophthalmologist. Anisometropia is not usually evident to the naked eye or through casual observation because it involves differences in the refractive error of each eye, which is not readily apparent in appearance.

Is anisometropia hereditary?

While there can be genetic factors at play, anisometropia is not solely determined by genetics and can develop in individuals without a family history of the condition.

Is anisometropia a progressive condition?

Anisometropia itself is not necessarily progressive, but its impact on vision and eye health can worsen over time if left untreated.

Meet Julie, our friendly Vision Therapist

​Julie has successfully completed the OEP (Optometric Extension Program) for Vision Therapy with the Australian College of Behavioural Optometrists.

Highly experienced, Julie has a deep passion for children's learning and development She specialises in enhancing visual processing skills through a variety of engaging and enjoyable vision-related activities.

Source of article:


Contact Panoptic Vision

Panoptic Vision Lake Cathie

1459 Ocean Drive, Lake Cathie, NSW 2445

Tel: (02) 6584 8900

Opening Hours:

Monday to Friday 8:30 am - 5:30 pm

Saturday By appointment only

Panoptic Vision Bellingen

2/58-60 Hyde St, Bellingen, NSW 2454

Tel: (02) 6655 2768

Opening Hours:

Monday - Thursday 9:30 am - 5:30 pm


bottom of page