Optic Neuritis and MS

Scary, But Not Often Permanent

Low angle view of a businessman suffering from a headache
Glow Images, Inc/Getty

You may have been told that you have a good chance of developing multiple sclerosis (MS) in the future if you've experienced a bout of optic neuritis. By some estimates, up to 80 percent of people with MS will experience vision-related symptoms, the most common being optic neuritis. In fact, twenty percent of people with MS experience optic neuritis as their first symptom. ​

This condition simply translates to “swelling of the optic nerve.” The optic nerve connects the eye to the brain, and MS can damage this connecting structure, resulting in optic neuritis.

If I Have Optic Neuritis, Will I Go Blind?

During a bout of optic neuritis, vision loss in the affected eye(s) can be quite substantial – even complete blindness is not uncommon. Thankfully, most people recover quite well and regain their vision, but it may take several months for a full recovery. However, some permanent residual loss of clarity or reduced color perception in the affected eye can happen.

It is important to know that optic neuritis can have different causes (and approaches to treatment), so even if you have MS and are fairly confident that is why you're experiencing visual problems, you must see your doctor. He or she will refer you to an ophthalmologist or neuro-ophthalmologist for evaluation. As with many of the other symptoms in MS, visual problems may come and go throughout the course of the disease. 

What Are The Symptoms of Optic Neuritis?

  • Most people with optic neuritis (about 90%) experience pain when moving their eyes. This pain usually subsides after a couple of days, even if vision is still affected.
  • Blurred vision, reduced light, flickering or flashes of light when the eyes are moved (called photopsia), loss of color vision (dyschromatopsia), a “blank spot” in the middle of the eye, called a scotoma.
  • Rapid onset (usually), with peak vision loss occurring within one to two weeks. 
  • More commonly affects one eye at a time. In about 10 percent of cases, symptoms occur in both eyes, either simultaneously or in rapid succession.
  • After a bout of optic neuritis, it is common to experience something called Uthoff’s Phenomenon, which is vision loss that comes on when your body temperature goes up, such as with a fever or in a hot climate. In fact, this experience can be an indication that a person had optic neuritis in the past that they may have been unaware of.
  • After experiencing optic neuritis, people may notice that their vision is better on some days than it is on others, or that they can see more clearly in the morning than they do in the evening.

What Causes Optic Neuritis in MS?

Optic neuritis in MS is caused by inflammatory demyelination of the optic nerve. In other words, the optic nerve becomes inflamed because of damage to its myelin sheath

How Is It Diagnosed?

An ophthalmologic examination is a critical feature of diagnosing optic neuritis, and a gadolinium-enhanced MRI of the brain and optic nerve may also be used. If you've already been diagnosed with MS, your doctor may skip right to treating you after your examination, if optic neuritis is found.


What is the Treatment and Recovery Like for Optic Neuritis?

High-dose corticosteroids, namely intravenous Solu-Medrol, has been shown to be effective in reducing the duration of optic neuritis, but probably has no effect on long-term vision. Over 90% of people begin to recover on their own within a month without steroid treatment. Oral steroids seem to have little benefit or even have adverse effects and should be avoided.

It seems as if optic neuritis will recur in 33 percent of people, either coming back in the other eye or affecting the same eye again.

My Bout with Optic Neuritis 

I experienced it soon after I was diagnosed with MS. I happened to be overseas, working on a research project. One evening I noticed that I had what I assumed to be a tiny spot in the middle of my contact lens. Not thinking much of it, I went to bed. The next morning, there was a silver-gray area in the middle of my field of vision that took away about 25% of my vision. By the end of the day, it was bigger and by the next day, I could only make out shapes on the periphery of my vision. If I sat still and concentrated, it would seem that objects would appear out of a fog, and then quickly recede.

Fortunately, I already knew that I had MS and I knew that optic neuritis was not really an emergency in the sense that I needed to be medically evacuated. Unable to get an earlier flight, I mustered through a couple more days of important meetings but was growing increasingly anxious due to not being able to see out of one eye in strange surroundings. In addition, it became very painful when I moved my eyes from side to side.

When I got home, I was immediately sent by my neurologist to a neuro-ophthamologist for an evaluation. Following a five-hour stint of testing, I was sent back to my neurologist’s office, who promptly hospitalized me for a five-day course of Solu-Medrol. I woke up on the morning following my first dose with my vision mostly restored and my pain gone.

My vision continued to improve during the course of steroids and over the next couple of months. A couple years later, I can say that the colors that I see out of that eye appear faded and I seem to have more problems focusing. Heat exposure makes this worse, including seemingly benign things like a shower that is a little too warm or standing over a hot stove for a prolonged period. In the end, I find myself reaching for the phrase that at times seems in danger of ringing false, but nonetheless, it fits: “I guess it could be worse.”


Chan JW. Optic neuritis in multiple sclerosis. Ocul Immunol Inflamm. 2002 Sep;10(3):161-86. Randall T. Shapiro. Managing the Symptoms of Multiple Sclerosis (5th ed.). New York: Demos Medical Publishing, 2007.

Balcer LJ. Optic neuritis. N Engl J Med 2006; 354:1273–1280.

Continue Reading