What Is Convergence Insufficiency?Convergence insufficiency (CI) is an eye condition that affects up to 17% of children and adults. It happens when your eyes have trouble working together to see something close up. When you look at something close to your face, your eyes should come together (or converge) to view the object. Convergence insufficiency affects and disrupts the nerves that control this process. Instead of both eyes turning toward what you're attempting to see, one of your eyes just can’t make it. What should look like a clear image is now blurry, doubled, or distorted.
How Is Convergence Insufficiency Caused?There are many possible causes of CI, including:
- Head injury: A concussion or brain injury can affect the nerves that control eye muscles.
- Eye strain: Students or professionals may develop CI if they spend excessive amounts of time reading or using computers.
- Stress: Some people develop CI during periods of personal stress — long hours, career difficulties, family pressures, and so on.
- Neurological or neuromuscular conditions: Patients with Parkinson's disease, a neurodegenerative illness, may develop CI. It may also be present in patients with the neuromuscular disease Myasthenia gravis.
Convergence Insufficiency SymptomsUnderstanding the symptoms of CI can help you seek treatment. Talk to a doctor if you've noticed any of the following symptoms in your day-to-day life:
- Sore or tired eyes
- Double vision
- Blurred vision
- Difficulty concentrating
- Problems with reading
- Rubbing the eyes
- Closing one eye when focusing up close
How is Convergence Insufficiency Diagnosed?CI is challenging to diagnose. Routine eye exams typically miss symptomatic convergence insufficiency. Therefore, it's important to pay attention to symptoms and whether they match with typical signs of CI. A doctor testing you for CI will take your general medical history and run exams.
- Measure the near point of convergence (NPC), the closest distance your eyes can focus without double vision. The doctor will hold up a small object like a pen or pencil and gradually move it closer to your eyes. Your NPC is where you see the object in double vision, or the examiner notices an eye drifting outward.
- Assess positive fusional vergence (PFV), a misalignment of the eye. The doctor will ask you to read an eye chart through prism lenses to test whether your eyes drift. You'll tell the doctor when you start to have double vision.
Convergence Insufficiency TreatmentCI treatment plans depend mostly on symptom severity. For most patients, vision therapy is the primary treatment. Options include:
- Computer vision therapy: Programs that use images on a computer screen to train the eyes and increase convergence ability. Most people undergo computer vision therapy in an office setting, but some programs involve at-home treatment.
- Pencil push-ups: An at-home treatment that involves moving a pencil slowly toward and away from your eyes. These eye exercises are typically done for 15 minutes a day, five to seven days a week, depending on a doctor's orders.
- Reading glasses: Support for your eyes as you go through vision therapy. Your doctor may recommend regular reading glasses to ease eye strain. There are also special prism glasses that can help with blurry or double vision.
When Convergence Insufficiency Treatment Doesn't WorkVision disorders are tricky to diagnose. Multiple conditions have similar symptoms, but the treatments for one condition don't work for another condition. If you've gone through CI treatment without success and you've exhausted what seems like all your available options, you may actually have binocular vision dysfunction (BVD). BVD shares symptoms with many other eye conditions, including CI.
What Is Binocular Vision Dysfunction?BVD happens when the eyes don't align properly. The brain forces the eyes into their "correct" position. This causes strain and fatigue in the eye muscles. At least one in 5 people struggle with BVD, but most people don't know about it. Many suffer through misdiagnoses and treatments that don't work — but the right BVD therapies can change all that. The first step is recognizing the symptoms.
Binocular Vision Dysfunction SymptomsBVD causes various symptoms, many of which are also symptoms of convergence insufficiency. Common BVD symptoms include:
- Neck pain
- Balance and coordination problems
- Changes in gait (walking)
- Distorted, shadowed, double, or blurred vision
Common Misdiagnoses of BVDIt's common for people with BVD to hear they have CI or one or more of the following conditions:
- Motion sickness
- Reading challenges
- Traumatic brain injury
- Chronic migraine
- Generalized anxiety disorder
When BVD Occurs Alongside Another ConditionIt's also possible to have BVD and one of the above conditions simultaneously. One particularly common link happens with traumatic brain injury (TBI). TBI frequently causes headaches and dizziness, and so does BVD. People with both conditions often seek out TBI-related therapies and medications for those symptoms but grow frustrated when treatments don't work. Doctors now know that TBI can cause BVD, which also brings on headaches and dizziness. BVD can also be present alongside any of the above conditions. If you have a related diagnosis and treatment isn't working, get tested for BVD.
BVD in ChildrenSchool-age children may also experience BVD. Some are born with the condition. Others develop it due to an injury like a concussion or head injury from sports. Watch your child for the following symptoms:
- Clumsiness such as trouble catching balls
- Reading and learning challenges
- Trouble focusing
Contact the Top Vision Specialists TodayAt Vision Specialists of Michigan, we've been treating BVD and other neurovisual conditions since 2004. Our founder, Dr. Debby Feinberg, is the original developer of NeuroVisual Medicine and has been treating patients with BVD and related disorders since 1995. If you think you might have BVD, take the online questionnaire that corresponds to your or your child's age, or contact us to schedule a NeuroVisual Evaluation. This thorough test can identify BVD and get you or your child on the road to recovery.