It can happen all of a sudden. Your vision gets dim or blurry. You can’t see colors. Your eyes hurt when you move them. It’s a condition called optic neuritis, and it’s a common problem for people living with multiple sclerosis (MS). The symptoms can seem scary, but most people recover fully, often without treatment.
What Is Optic Neuritis?
When you have optic neuritis, the nerve that sends messages from your eye to your brain, called the optic nerve, is inflamed. Sometimes, it means the nerve loses the fatty coating that covers and protects it, called myelin. Without it, the optic nerve can't send the right signals to your brain. This can lead to sudden changes in your vision.
Optic neuritis is one of the most common symptoms of the relapsing-remitting form of MS. But it can also happen with diseases such as Neuromyelitis Optica (NMO), diabetes, or when you take certain medications. Neuromyelitis Optica (NMO), also known as Devic's disease, is an autoimmune disorder in which immune system cells and antibodies primarily attack the optic nerves and the spinal cord, but may also attack the brain.
What Are the Symptoms?
Optic neuritis usually comes on quickly, over a few hours or days. You may notice some of these symptoms:
- Blurred vision
- Loss of color vision
- Pain when you move your eyes
- Trouble seeing to the side
- A hole in the center of your vision
- Blindness in rare cases
Adults usually get optic neuritis in only one eye, but children may have it in both.
Some people get better in a few weeks, even without treatment. For others, it can take up to a year. And a few people never fully regain their sight. Even when other symptoms clear up, they may still have trouble seeing colors or at night.
How Do I Know I Have It?
If your doctor thinks you have optic neuritis, she’ll refer you to a doctor who treats eye diseases, called an ophthalmologist. You'll likely have tests to check:
- Your color vision
- The smallest letters you can read on a chart
- How well your eyes respond to light
- The appearance of your optic nerve
Your doctor might also use an imaging test called magnetic resonance imaging (MRI) to look at your brain and optic nerves to know for sure if you have optic neuritis and to look for signs of MS. During the test, she may inject a dye into a vein in your arm. The dye makes the optic nerve and other parts of your brain easier to see on the MRI.
What's the Treatment?
Optic neuritis often goes away on its own. To help you heal faster, you may get high-dose steroid drugs through an IV. This treatment may also lower your risk of other MS problems or delay its start.
In special cases, your doctor may suggest other treatments, such as:
- IVIG. This is a medication made from blood. You get it through a vein in your arm. It’s costly and doctors aren’t completely sure that it works. But it may be an option if you have severe symptoms and can't use steroids or they haven’t helped you.
- Vitamin B12 shots. It’s rare, but optic neuritis can happen when the body has too little of this nutrient. In these cases, doctors can prescribe extra vitamin B12.
Once your vision is back to normal, you can get optic neuritis again, especially if you have MS. If your symptoms return, be sure to tell your doctor. Report any new symptoms or those that get worse, too.