What is Binocular Vision Dysfunction (BVD)?

Binocular Vision Dysfunction (BVD) is a serious eye condition where the eyes are misaligned, sending two different images to the brain. The brain struggles to merge these two different images into one clear image, causing symptoms such as headaches, dizziness, anxiety, motion sickness, and chronic neck pain.

The condition can be caused by facial asymmetry similar to adults, or it can be caused by a concussion or head injury, such as from a soccer game or falling while riding a bike. Some research suggests that at least 20% of adults experience some symptoms of BVD that may be interfering with their everyday lives. Someone you know may be suffering from binocular vision dysfunction and not even realize it. Exactly why some people develop BVD and others don’t often isn’t clear.

Early research has found that BVD can be genetically inherited and run in families, most often from mother to daughter. In other clinical research, there is a direct correlation between head injury or concussion and the onset of BVD symptoms. There is also a connection between BVD and acquired brain injuries caused by a stroke, Lyme disease, COVID-19, and Mono (Mononucleosis).

Yes, BVD symptoms are often mistaken for a number of other conditions since many medical and eye doctors don’t know how to screen for and diagnose BVD. Patients are regularly but mistakenly told they have one of the following conditions, while in reality BVD is the main cause of their symptoms:

  • Agoraphobia
  • Anxiety / Panic disorders
  • ADD / ADHD
  • Cervical misalignment
  • Meniere’s Disease
  • MS (Multiple Sclerosis)
  • Reading Comprehension Issues
  • Sinus problems
  • Psychogenic dizziness / Chronic Subjective Dizziness
  • BPPV (Benign Paroxysmal Positional Vertigo)
  • PPPD (Persistent Postural-Perceptual Dizziness)
  • Vestibular Migraine / Migraine Associated Vertigo (MAV)
  • TMJ (temporomandibular joint) disorders

Find out if you are struggling with BVD: TAKE THE BVD TEST

Take BVD Questionnaire

What to expect: The NeuroVisual™ Exam

While at least 20% of the population suffers from Binocular Vision Dysfunction, almost no one knows about this condition. To make matters more difficult, people suffering from BVD have a small amount of vision misalignment not found in a routine eye exam.

A comprehensive binocular vision assessment is the best way to find out if you have binocular vision dysfunction. A NeuroVisual™ trained eye doctor can successfully diagnose BVD through a specialty binocular vision exam designed to assess your entire visual and physical system. In addition to standard eye exam tests, the eye doctor will assess the following:

  • Eye movement
  • Eye teaming and tracking
  • Eye focusing
  • Binocular fusion
  • Balance and gait stability
  • Posture and neck alignment
  • Visual convergence
  • Visual-spatial awareness
  • Blood pressure and heart rate
  • Depth perception

Yes, patients can have both 20/20 vision and Binocular Vision Dysfunction. During a routine eye exam, each eye is checked individually, but patients are not regularly assessed for how well their two eyes work together. Patients who see 20/20 have a high level of acuity in each eye, but this measurement doesn’t tell us anything about how the patient’s two eyes are working together as a team (i.e.- binocular vision).

The thorough NeuroVisual™ Exams performed in our clinic evaluate patients’ binocular vision to determine what is causing their BVD symptoms and to custom fit microprism lenses to relieve these symptoms.

For more on binocular vision dysfunction or and to get tested for BVD, take the BVDQ™, our Free 5 Minute Self Test to find out if you have BVD.
Take BVD Questionnaire

What are prism glasses?

Treating Eye Misalignment and Binocular Vision Dysfunction (BVD)

When your eyes are misaligned, your eyes are sending two different images to the brain which it has trouble merging. When the brain receives conflicting information from each eye, it strains the eye muscles to try and correct the misalignment – this causes the symptoms of BVD. A small percentage of patients with BVD have diplopia (or double vision) but most patients do not see double, yet they suffer from symptoms like migraines, dizziness, car sickness, and light sensitivity.

Prism glasses have provided tens of thousands of patients with life-changing relief, and wearing prisms can feel different than glasses you might already wear. It can take several days to acclimate to your new prism glasses. When you first begin wearing prism glasses, your body will undergo a process of change we call Progressive Relaxation. Your BVD symptoms will start to subside, and the feeling might take some getting used to. After wearing your prisms for 2-4 weeks, your symptoms might return which tells us you are ready for your next exam, the Progress Assessment.

The vision misalignment you measured during your initial NeuroVisual™ Exam may measure differently during your Progress Assessment exam several weeks later. We tell patients that ‘the first prism prescription is never the final prism prescription’ because as your body and eyes relax, the prescription will adjust and shift. During your Progress Assessment exam, your optometrist will remeasure your visual system and fine-tune your prism prescription with your body in its new, more relaxed state.


Any optometrist can prescribe prism lenses, but not every optometrist is specially trained to prescribe microprisms. There is an art and science to prescribing microprisms. Dr.Zhang has undergone intensive training with the NeuroVisual™ Medicine Institute to become an expert in prescribing microprisms and treating Binocular Vision Dysfunction.


Any new glasses can cause eye strain for the first few days. Incorrect prism prescriptions can cause BVD symptoms to become worse, as can improperly adjusted glasses frames. If this happens, tell your doctor immediately so that the frames and the prescription can be checked.

For more on binocular vision dysfunction and to see if microprism glasses might provide relief for your BVD symptoms, take the BVDQ™, our Free 5 Minute Self Test to find out if you have BVD.

Take BVD Questionnaire

What do patients and referring doctors say about NeuroVisual™ Medicine and microprism glasses?

Patient Testimonials & Doctor Testimonials

What Patients Say About their Binocular Vision Dysfunction and Microprism Glasses

With over 50,000 patients treated for BVD by NeuroVisual™ trained optometrists across the globe, there are a lot of patient stories of success, relief, and transformation. Patients of all ages have been affected by BVD and have received successful treatment with microprism glasses. Read and watch patients tell about their life changing NeuroVisual™ Exams and now living with greatly reduced symptoms with their microprism glasses.

Wendy’s Path to Migraine Relief

Robert ‘Gets Back in the Game’ after Car Accident

Noah’s Handwriting, Hand-eye Coordination, and Confidence

Laurelle Becomes Migraine Free

Learn what doctors have to say about BVD

What Doctors Have To Say About BVD

The network of medical professionals who refer patients to us for care has contributed to a growth in Binocular Vision Dysfunction awareness. What our collective research has taught us is that oftentimes patients have experienced doctors attempting to treat their symptoms rather than the actual cause – which could very likely be a patient’s eyes. This leads to patients being misdiagnosed and prescribed medications that do not help and therapies that do not bring relief.

When treated with microprism lenses for their BVD, the average patient experiences an 80% reduction of symptoms by the end of treatment.

NeuroVisual Medicine Institute Testimonials

FAQs of Binocular Vision Dysfunction

Our Frequently Asked Questions contain common questions we receive relating to Binocular Vision Dysfunction.

Binocular Vision Dysfunction (BVD) is a serious eye condition where the eyes are misaligned, sending two different images to the brain. The brain struggles and overuses the eye muscles to merge these two different images into one clear image, causing symptoms such as headaches, dizziness, anxiety, motion sickness, and chronic neck pain.

BVD is treated by correcting eye misalignment with our specialized microprism lenses. They bend light in such a way that the misaligned images are once again realigned. Once this occurs, the eye muscles no longer have to strain, providing significant relief from headaches, dizziness, blurred vision, and all other symptoms.

Patients oftentimes report feeling noticeably better immediately. The average patient suffering from BVD will notice a 50% reduction of symptoms by the end of their first visit. Over the next several visits, the prism lenses are fine-tuned and continue to improve and eliminate the symptoms of BVD.


Yes, many patients with BVD experience difficulty with driving. This is because two common symptoms associated with the condition are dizziness and difficulty with depth perception, which alters your balance and equilibrium, making it difficult to see the road, signage, and nearby cars. Driving at night and anxiety while driving are also common symptoms for BVD patients.


BVD can be the result of your facial asymmetry (where one eye is higher than the other), nerve or eye muscle abnormality (a common condition many people are born with), or it can develop as a result of stroke, concussion / brain injury, or a similar neurological disorder.


To determine if your symptoms are the result of Binocular Vision Dysfunction, we suggest you first see your primary care physician or specialist to rule out other causes for your symptoms. If no cause is found for the symptoms, then BVD might be the issue.

  1. We ask you to fill out a specialized questionnaire designed to help diagnose those who have BVD.
  2. You will be asked to complete a detailed Health History form.
  3. An eye exam is performed to determine the need for correction of nearsightedness, farsightedness, and astigmatism (a common imperfection in the eye’s curvature).
  4. A specialized exam is performed (NeuroVisual™ Evaluation) to determine if vision misalignment is present.
  5. If diagnosed with BVD, you will be fitted with a trial version of your new prescription during your exam. Most people notice a significant improvement in their symptoms within just a few minutes of putting on the trial lenses.

You can expect to spend approximately 3 hours in our office during your visit.


Every person can receive treatment for BVD, as long as they are old enough to wear the specialized prism glasses and be able to tell (or show) the doctor how they feel. The youngest patient that has been helped was 8 months old. There is no upper age limit.


Yes, but it is important that individuals with a traumatic brain injury be thoroughly evaluated by their doctor to rule out other causes of symptoms (including dizziness and headaches). If no other cause is found, Dr.Zhang can conduct a NeuroVisual™ Evaluation to determine if BVD is the cause of your symptoms. Even if you have experienced BVD symptoms for decades, you can still receive effective treatment for the condition.

Contact Us for More Info

Have questions? Please feel free to contact us with any additional questions you might have – We are more than happy to assist and provide you with the information you need. Call us at Centereach Vision or email us: eyedoczhang@gmail.com.

If these symptoms sound familiar and you believe that you might have BVD, get relief now and take the BVDQ™, our Free 5 Minute Self Test to find out if you have BVD
Take BVD Questionnaire