In today’s digital age, many individuals suffer from various forms of eye strain, often without realizing the underlying causes. One common, yet often overlooked, form of eye strain is BVD (Binocular Vision Dysfunction). This condition occurs when the eyes struggle to work together efficiently, leading to discomfort and a range of symptoms.
In this blog post, we’ll dive deep into understanding BVD eye strain, explore its symptoms and causes, and provide effective relief strategies to help you mitigate this condition.
BVD Eye Strain
Binocular Vision Dysfunction (BVD) refers to a condition where your eyes and brain don’t work together correctly. This keeps you from seeing the world as a single, seamless picture. Rather than a specific condition, BVD is an umbrella term that encompasses several conditions affecting the eyes, nervous system, and brain. These include crossed eyes (strabismus) and lazy eye (amblyopia), among others.
In a normal visual system, each eye captures a slightly different image of the same object. These images are sent to the brain, which processes and merges them into one unified perception. This process has three key stages:
- Macular Perception: Each eye focuses clearly on the same object, capturing fine details.
- Fusion: The brain combines signals from both eyes into a single image.
- Stereopsis: Depth perception is achieved as the brain interprets the different angles and distances perceived by each eye.
Binocular vision develops in the visual cortex of the brain over time, as the brain learns to synchronize the inputs from both eyes. However, disruptions in this system can lead to vision problems such as:
- Strabismus (Crossed Eyes): Misalignment causes one or both eyes to turn inward (esotropia), outward (exotropia), or vertically (hypertropia or hypotropia).
- Diplopia (Double Vision): Misaligned eyes send two different images to the brain, causing double vision.
- Suppression: To avoid double vision, the brain may suppress one eye’s image, potentially leading to further complications.
When there’s a disruption in any of these stages, symptoms of BVD emerge. Many forms of BVD are uncommon, but conditions like lazy eye affect between 6 million and 13 million people in the U.S. alone. Comprehensive eye exams are essential for diagnosing conditions like BVD or identifying factors contributing to digital eye strain, ensuring proper treatment and relief.
Types of Binocular Vision Dysfunction
Convergence Insufficiency
Difficulty in turning the eyes inward to focus on nearby objects.
Symptoms:
- Blurred or double vision while reading.
- Eye strain and headaches during prolonged near work.
- Difficulty maintaining focus on close-up tasks, such as reading, writing, or using a computer.
- Words may appear to move, swim, or blur.
Cause: Weakness in the muscles responsible for bringing the eyes inward or improper coordination between the eyes.
Convergence Excess
A condition in which the eyes turn inward more than necessary while focusing on near objects.
Symptoms:
- Eye strain during reading or close-up tasks.
- Headaches, particularly around the temples or the eyes.
- Nausea and dizziness when performing close work.
- Difficulty transitioning focus from near to far.
Cause: Overactive or excessively strong inward-turning muscles in the eyes.
Vertical Heterophoria
Definition: A misalignment in which one eye is slightly higher than the other.
Symptoms:
- Double vision or overlapping images.
- Dizziness and unsteadiness, particularly while walking or driving.
- Neck and shoulder pain from tilting the head to compensate for the misalignment.
Causes: Vertical heterophoria can be caused by traumatic brain injuries, congenital abnormalities, or muscle imbalances in the eyes.
Symptoms of Eye Strain
The symptoms of BVD-related eye strain can vary, but they commonly include:
Pain Effects
- Eye pain and strain (asthenopia).
- Headaches, particularly around the eyes or temples.
- Pain when moving your eyes.
Visual Effects
- Blurred or double vision (diplopia).
- Light sensitivity (photophobia).
- Shadowed vision or trouble focusing on objects up close.
- Difficulty seeing at night (nyctalopia) or recognizing small, faint, or distant objects.
- Issues with digital screens, known as computer vision syndrome.
Nonvisual Sensory Effects
- Dizziness, balance issues, or vertigo (a spinning sensation).
- Motion sickness, nausea, or trouble walking in a straight line.
- Hand-eye coordination problems, making it hard to throw, catch, or avoid objects.
Reading Effects
- Losing your place while reading or needing a finger or bookmark to follow lines.
- Eye fatigue and skipping lines.
- Words appearing to run together or difficulty comprehending text despite multiple read-throughs.
Psychological Effects
- Avoidance of crowded or brightly lit environments.
- Anxiety or fear in public settings or while driving.
- Difficulty maintaining eye contact in face-to-face interactions.
What Causes Eye Strain?
Several factors can cause BVD or exacerbate eye strain. These include:
- Sight Issues: Refractive errors such as nearsightedness (myopia), farsightedness (hyperopia), astigmatism, or age-related presbyopia.
- Eye Issues: Physical misalignments such as crossed eyes (strabismus) or lazy eye (amblyopia).
- Neurological Issues: Problems with nerves controlling eye movement or visual processing in the brain, as seen in conditions like migraines, strokes, or attention-deficit/hyperactivity disorder (ADHD).
- Multi-factor Causes: Concussions or traumatic brain injuries (TBIs), which can disrupt eye alignment and visual processing and combination conditions, such as having amblyopia and later developing a stroke. Other contributing factors include prolonged screen time, poor lighting, and outdated eyewear prescriptions.
Diagnosis and Treatment of BVD
A comprehensive eye exam is the first step in diagnosing BVD. Eye specialists assess alignment, depth perception, and refractive errors to determine the root cause.
Treatment Options
- Eyeglasses or Contact Lenses: Correct refractive errors to improve clarity.
- Prism Glasses: Special lenses that help align the eyes, reducing misalignment-related strain.
- Vision Therapy:
- A personalized program of exercises designed to strengthen eye muscles and improve coordination.
- Leverages neuroplasticity—the brain’s ability to adapt—to retrain the visual system.
- Vision therapy is particularly effective for both children and adults with misaligned eyes, enhancing eye teaming and achieving clear, comfortable vision.
How to Relieve Eye Strain
Relieving eye strain requires a multifaceted approach, addressing both the symptoms and the underlying causes. Here are some strategies you can implement to reduce discomfort:
- Follow the 20-20-20 Rule
Take a 20-second break every 20 minutes by looking at something 20 feet away. This simple habit helps your eyes rest and refocus, reducing strain from screens. - Optimize Lighting in Your Workspace
Use soft, indirect lighting to minimize glare from windows or overhead lights. Proper lighting can significantly reduce stress on your eyes. - Keep Your Glasses Prescription Updated
Visit an optometrist to ensure your prescription is accurate, especially if you experience strain while reading or using digital devices. - Incorporate Eye Exercises
Try focusing on distant objects, following a pen with your eyes, or blinking more often. These exercises relax the muscles around your eyes and ease discomfort. - Use Blue Light Blocking Solutions
Consider wearing blue light-blocking glasses or using screen filters. These tools help combat digital eye strain caused by prolonged exposure to screens. - Stay Hydrated
Drink plenty of water throughout the day to prevent dehydration, which can lead to dry eyes and added discomfort. - Consult an Eye Specialist
If symptoms persist, seek professional advice. Learn more tips to reduce eye strain here, including insights on vision therapy and tailored treatment plans.
Visit Vision Gallery for Expert Eye Care and Relief from Eye Strain
BVD eye strain can be frustrating, but understanding its symptoms and causes can help you manage it. Whether it’s adjusting your screen time, updating your eyewear, or seeking professional advice, there are many ways to reduce eye strain and improve your vision.
At Vision Gallery, we offer expert eye care tailored to your needs. Our team can help you address BVD eye strain and other vision concerns with personalized solutions, from custom eyewear to advanced treatments.
