Binocular Vision Anomalies

What Are Binocular Vision Anomalies?

Binocular vision anomalies are a group of eye conditions that affect the way our eyes work together. They can lead to a range of symptoms, from strabismus to double vision.

Binocular vision anomalies are eye disorders that disrupt the coordination between our eyes, making it challenging to align them properly. Normally, our eyes work together to create a single, three-dimensional image of the world around us. However, when binocular vision anomalies occur, this teamwork falters.

The correct functioning of binocular vision without symptoms is dependent on various aspects that can be classified into three categories: anatomy, the motor system, and the sensory system.

Prevalence of BVA

Amblyopia affects around 3% of the population. Furthermore, strabismus affects between 2-3% people worldwide.

”Binocular vision anomalies are likely to affect approximately one in five patients consulting primary eyecare practitioners.”

What Causes Binocular Vision Anomalies?

Muscular Imbalance: Problems with the eye muscles that control eye movements can lead to misalignment.

Neurological Issues: Conditions affecting the brain’s ability to process visual information can disrupt binocular vision.

Genetics: Some individuals may have a genetic predisposition to certain binocular vision anomalies.

Eye Injuries or Diseases: Trauma or certain eye diseases can lead to strabismus or other binocular vision problems.

Common Types of BVA

Strabismus: Also known as “crossed eyes”, strabismus is a condition where the eyes are misaligned. This misalignment can be constant or intermittent and may affect one eye or both.

Convergence Insufficiency: This condition occurs when the eyes have difficulty working together to focus on a nearby object. People with convergence insufficiency often experience eye strain and double vision when reading or performing tasks up close.

Divergence Insufficiency: In contrast to convergence insufficiency, divergence insufficiency affects the ability of the eyes to move apart comfortably when focusing on distant objects. This can lead to difficulty in maintaining clear vision at a distance.

Amblyopia: Often referred to as “lazy eye,” amblyopia is a condition in which one eye doesn’t develop normal vision during childhood. It can result from strabismus or a significant difference in the prescription between the two eyes.

Nystagmus: Nystagmus is a condition characterized by involuntary eye movements that can cause significant challenges in visual function.

Classification of Binocular Vision Anomalies

BVA in the Primary Eyecare Practice

The procedure for checking every patient’s eyes and vision in primary eyecare should have three goals:

1. To detect the presence of anomalies
2. To suggest when further tests are needed
3. To establish the management: further investigation, refractive or prismatic correction, treatment (vision therapy), or referral for medical attention.

What Refractive Correction (If Any) Should be Worn When Performing Binocular Vision Tests?

The answer to this question is determined on the clinician’s needs.

1. To determine whether symptoms in everyday life are connected to BVA: Binocular vision tests should be performed with the patients wearing the optical correction, if any, that they would use most often for that job in everyday life.

2. To determine the impact of a suggested refractive correction on a patient’s binocular vision status: Tests should be performed while the patient is wearing the proposed refractive correction.

Treatment of Binocular Anomaly

Binocular vision disorders are treated using glasses, prisms, vision therapy, or surgery. Read more about vision therapy here.

Frequently Asked Questions

Source: Pickwell’s binocular vision anomalies. (2022a). In Elsevier eBooks. https://doi.org/10.1016/c2018-0-03169-2