Internuclear ophthalmoplegia, or INO ophthalmoplegia, is an eye movement disorder. The primary internuclear ophthalmoplegia symptom is the inability to look to one side of your face with both of your eyes at the same time. This disorder can be present in one or both of your eyes. It is usually a symptom of another medical condition or event. Read more to learn about internuclear ophthalmoplegia.

What Are the Causes of Internuclear Ophthalmoplegia?
Internuclear ophthalmoplegia causes can be traced to damage to the cranial nerve fibers that move your eyes from side to side. This damage is caused by a variety of other medical conditions. The most common of these are:

  • Multiple sclerosis. A disease that affects the nervous system. Your own body attacks the protective layer over your nerve fibers. This causes the communication between various parts of your body to become impaired. It is common for people who have multiple sclerosis to also develop vision impairments like internuclear opthalmoplegia.
  • Stroke. A stroke happens when the blood flow to your brain is cut off or limited. This can cause your brain tissue to be without crucial oxygen and other substances that it needs to function. If parts of your brain are left without oxygen even for just minutes, they can die. Strokes can cause internuclear ophthalmoplegia by depriving the fibers that help your eyes move of oxygen.
Rarer causes of internuclear ophthalmoplegia include:

  • Cancer
  • Encephalitis
  • Head injuries
  • Hemorrhages
  • Lyme disease
  • Medications
  • Certain infections
What Are the Symptoms of Internuclear Ophthalmoplegia?
Symptoms of internuclear ophthalmoplegia include the inability to turn an eye toward your nose. You may also get double vision when you look to the side. If you just have one affected eye and you look toward the side of the affected eye:
  • Your affected eye will turn inward but will not be able to move to the middle. Instead, the eye will stare straight ahead.
  • If your unaffected eye moves toward your ears, it will repeatedly make fluttering motions in the opposite direction.
In order for your doctor to diagnose internuclear ophthalmoplegia, they will need to perform the following tests:
  • Medical examination. Your doctor will need to perform a physical exam.
  • Imaging tests. In some situations, your doctor will order an MRI or CT scan to learn more about the underlying cause of your internuclear ophthalmoplegia.
  • Blood and cerebrospinal fluid examinations. If you think you may have internuclear ophthalmoplegia but do not know what is causing it, this test may help uncover some of the less common causes.
How Do You Treat Internuclear Ophthalmoplegia?
Since internuclear ophthalmoplegia is usually a symptom of another medical condition, your treatment will often be centered around treating that condition. Often, INO ophthalmoplegia can be the symptom that lets you know you have multiple sclerosis. If you have multiple sclerosis, you will need to treat both MS attacks and the overall progression of the disease. These treatments can range from daily medications, injectable treatments, infusions, physical therapy, and pain management methods.

Stroke recovery will vary significantly from person to person. It also depends on the type of stroke and your overall medical situation.
If you have internuclear ophthalmoplegia from an infection, accident, or medication, you will most likely recover. Some of the things your doctor might suggest you do to treat your internuclear ophthalmoplegia include:
  • Botox treatments to reduce misalignment around your eyes
  • Medical lenses like Fresnel prism lenses
  • Surgery‌
  • Even after treatment, your doctor will probably follow up with additional tests. This is especially true for people recovering from strokes or multiple sclerosis.