Optic Neuritis (ON) | Symptoms & Causes
What are the symptoms of ON?
The symptoms of ON can affect one or both eyes. They include:
- blurred vision
- loss of color vision
- complete loss of vision
- eye pain
What causes ON?
ON is an "autoimmune" condition that often follows an infection such as a cold. Your immune system protects your body from things like bacteria and viruses, but autoimmune diseases confuse your body's immune system. Instead of fighting against bacteria or viruses, it attacks your healthy cells and tissue. In ON, your immune system reacts against your optic nerve. Autoimmunity is not contagious, but it may be genetic (inherited from parents).
ON may also follow a vaccination, although this is rare. In some cases of ON, a specific trigger/cause cannot be identified.
Optic Neuritis (ON) | Diagnosis & Treatments
How is ON diagnosed?
There’s no specific test used to diagnose ON, but there are several exams and tests your doctors may choose to look at, including:
- your child's medical history
- a neurological examination
- a brain MRI scan to look for swelling in the optic nerve
- a lumbar puncture (spinal tap) to make sure that there is not an infection in the spinal fluid, such as meningitis or encephalitis, and to measure the pressure in the spinal fluid
- blood tests to look for infectious triggers and for other conditions that can be confused with ON
- special eye tests of side vision (called visual fields) and the electrical function of the optic nerve (called visual evoked potentials), performed by an eye doctor (ophthalmologist)
In order to perform the testing and undergo treatment, children with ON are usually hospitalized for a week.
How is ON treated?
Medications are used to reduce the inflammation (swelling) in the optic nerve in ON. The main medication that is used is called methylprednisolone (Solu-medrol™), which is a corticosteroid given by IV once a day for three to five days. This medication is completely different from the illegal steroids that some athletes use. Most children with ON improve with high doses of methylprednisolone.
Optic Neuritis (ON) | Frequently Asked Questions
Most children tolerate medication very well, although some children can develop temporary moodiness or other behavioral changes.
Steroids can also cause increases in blood pressure and blood sugar, which your doctors and nurses will check for and treat if necessary. In addition, steroids can irritate the stomach lining. In such cases, medication such as ranitidine (Zantac™) is usually given to prevent stomach irritation.
Some children will be placed on a steroid medication for a short time. While on prednisone, a medication to prevent your child from having stomach irritation may also be prescribed.
Steroid treatment can reduce some visual symptoms and stop new symptoms from developing. Although the long-term prognosis for children with ON varies, most children make a complete or nearly complete recovery, including those children with initially severe symptoms. For most children, recovery begins within days and continues for up to one year. Some patients can have residual symptoms such as blurred vision or decreased color vision.
Most children return to their baseline school performance, but some children may have new difficulty with their school work. This may be due to several factors, including missed school days during the illness, as well as changes in vision. If you notice changes in your child's school performance, it's important to let your medical providers know so that they can work with the school to develop an educational plan.
No. In most patients, ON occurs only once; in some patients, however, it can reoccur. When it reoccurs, the symptoms can be identical to the initial episode but can also be different. It is not known why patients develop ON with certain infections at certain times.
If you notice symptoms during an infection that you think are unusual — such as confusion, changes in vision, weakness, numbness, or imbalance — it is important to notify your doctor immediately.
Both ON and multiple sclerosis (MS) involve autoimmune responses to myelin; they are both "demyelinating" disorders. Symptoms common to both disorders include loss of vision. Corticosteroids are used to treat attacks of both ON and MS.
Although children can develop MS, it is much more common in adults. Common symptoms of MS, such as weakness, numbness, or loss of balance, do not occur in ON.
There are also clues on brain MRI to distinguish ON from MS. Most importantly, ON typically occurs only once, while patients with MS have further, repeated attacks of inflammation in the brain and spinal cord. Most patients with MS are treated with ongoing medication to prevent such attacks. Patients with ON don't need such medication.
Although most children do not, some children who initially have ON can develop MS if they have new attacks affecting other parts of the brain or spinal cord. For this reason, it is important to have ongoing follow-up with your doctor. If you notice new symptoms, such as visual loss, weakness, numbness, or loss of balance, it is important to let your doctor know immediately.
After you leave the hospital, it's important to follow up with your neurologist and ophthalmologist in the outpatient clinic. We will perform a neurological and eye examination on your child. A follow-up brain and/or spinal cord MRI and visual field testing may also be done.
