Per a review published in June 2021 in Neurology and Therapy, the most common vision problems among people who have MS include reduced visual sharpness and contrast sensitivity, changes to color vision, and ocular motility disorders (disorders that affect the motion of the eyes). Some of the eye complications associated with MS include optic neuritis, nystagmus, and diplopia. However, the prognosis is good for recovery from many of these vision problems, notes the NMSS. Vision problems can negatively affect quality of life for people living with MS, due to reduced ability to participate in activities, daily life limitations, and decreased driving ability, according to the Neurology and Therapy review. If you have any symptoms affecting your eyes or vision, see your doctor. It’s important for people with MS to have regular visits with an ophthalmologist to help diagnose and treat the eye conditions that can occur when you have MS, notes the American Academy of Ophthalmology.
Optic Neuritis
Optic neuritis, or inflammation of the optic (vision) nerve, is a common symptom of MS, according to the NMSS. The condition is the first symptom of MS for about 20 percent of people who have the disease, and 50 percent of people who have MS experience it at some point in their disease course, according to the Neurology and Therapy review. While the specific cause of optic neuritis is unknown, it’s thought to develop when your immune system erroneously attacks the substance covering your optic nerve, which leads to inflammation and damage, notes the Mayo Clinic. Optic neuritis typically occurs in one eye, but in some cases, you may experience it in the other eye at a later date, per the NMSS. The condition may cause pain with eye movement, blurry vision, dim vision, or loss of color vision. A blurred or dim spot (scotoma) may occur in the center of your visual field, or you may completely lose your vision in the affected eye. However, in most cases, vision returns. “Ninety percent of people who have optic neuritis go back to high-contrast twenty-twenty vision,” says Scott Newsome, DO, associate professor of neurology at Johns Hopkins Hospital in Baltimore, “but low-contrast visual acuity [sharpness] is impaired, making it difficult to see at dusk.” This can result in difficulty driving, in particular. Treatment commonly includes high doses of glucocorticoids, such as intravenous methylprednisolone or prednisone pills. “For acute attacks of optic neuritis, the gold standard for treatment is still IV steroids,” says Dr. Newsome. Even after successful treatment, residual symptoms are possible, notes the NMSS. If you are very tired or overheated, you may notice that your vision dims or blurs, which is known as Uhthoff’s phenomenon. Rest and cooling off will usually help your vision return. If you have nystagmus, you may perceive the world as wiggling, and “it can make people feel sick to their stomach or unbalanced,” says Newsome. You may find that you hold your head at an angle to reduce symptoms, notes the NMSS. Nystagmus can occur in MS if the parts of the brain that control eye movements are damaged, according to MedlinePlus. The condition may go away and come back, or it may be persistent, per the NMSS. While treatment is limited, it may include off-label use of medications such as gabapentin. “This is one of the more challenging things to treat,” says Newsome, who typically uses medication as first-line therapy for the nystagmus. “There are no surgeries that can treat nystagmus, but vestibular rehab can help with some of the dizziness and balance problems.”
Diplopia
MS can cause damage to the nerves that control the muscles that allow eye movement. When this happens, eye movements are no longer coordinated, and diplopia or double vision occurs, according to the NMSS. This may cause you to see two side-by-side images or one image on top of another. Diplopia may be fleeting or persistent. In some cases, it gets better without treatment. When diplopia is a new symptom, it may be part of an MS relapse, and a brief course of corticosteroids may help, notes the NMSS. If you don’t respond to steroid treatment, doctors may recommend plasmapheresis, in which the liquid portion of the blood (the plasma) is removed and most commonly replaced with albumin or other proteins, says Newsome. Once double vision is under control, eyeglasses containing prisms can be used to bring the images seen by one eye into alignment with those seen by the other eye. Patching one eye can also be beneficial for driving or other short tasks, per the NMSS. If prisms and patches don’t work well, strabismus surgery to realign the eyes may be an option, according to NYU Langone Health. But, says Newsome, “Many patients will continue to recover from an attack over six months or even a year to a year and a half, so prisms and corrective surgery should not be considered early on.”
Internuclear Ophthalmoplegia
Internuclear ophthalmoplegia (INO) is characterized by impaired horizontal eye movement, according to the Merck Manual. It is caused by damage to connections between nerve centers in the brain stem. Symptoms may include blurry vision, double vision, and dizziness. Nystagmus often occurs in one eye during horizontal gaze. Another symptom is oscillopsia, or when a stationary object appears to move. Many patients have no symptoms, notes the NMSS. According to an article published in June 2020 in StatPearls, about one-third of INO cases are caused by strokes. These cases typically occur in older people, and usually affect only one eye. But “if a young, otherwise healthy person has it, MS has to be at the top of the list of possible underlying causes,” says Newsome. Per the StatPearls article, disorders like MS cause another third of cases of INO. When MS is the cause, the condition usually affects both eyes, and occurs in young adults and adolescents. Some studies have shown that about 23 percent of people who have MS also have INO. If you are having any issues with your eyes, be sure to talk to your doctor or ophthalmologist, as treatments are available that can help improve your vision and your quality of life.
