Vision disturbances can be an early indicator of multiple sclerosis (MS), an incurable autoimmune disease that affects the central nervous system. While symptoms like walking difficulties and balance issues are more commonly associated with MS, problems with the optic nerves can precede these more familiar signs, according to medical experts.
Sasha Clark, now 28, experienced sudden vision changes in January 2018, initially mistaking it for a migraine. She noticed she could only see clearly with one eye closed. Within two weeks, her condition worsened, impacting her coordination, balance, and energy levels, leading to her being unable to leave her home. Two months later, she was diagnosed with MS.
MS damages myelin, the protective sheath around nerves, particularly in the brain and spinal cord. This damage can also affect the optic nerves, disrupting the communication between the eyes and the brain. This disruption can lead to optic neuritis, a condition characterized by symptoms such as eye pain, blurred vision, blind spots, washed-out colors, and flashing lights, which typically develop over several days. Although optic neuritis often resolves on its own, it can be the first manifestation of MS.
Research published in 2025 indicated that visits to neurology and ophthalmology specialists may increase eight to nine years before an MS diagnosis. "There is a lot more awareness of the early symptoms of MS now," said Dr. Aravinthan Varatharaj, a clinical academic neurologist at the University of Southampton. "But while many people are familiar with MS symptoms caused by damage to the brain and spinal cord, such as walking problems, balance issues and bladder or bowel difficulties, far fewer know how MS can affect the optic nerves and vision. The optic nerves are heavily coated in myelin, making them particularly vulnerable to damage from MS."
Beyond optic neuritis, MS can also affect nerve pathways controlling eye movements, leading to double vision, difficulty reading, or distorted straight lines. These visual symptoms, often accompanied by balance issues or nausea, typically evolve over days and may improve with prompt treatment. Specialists emphasize the importance of recognizing these symptoms and seeking medical evaluation, as early identification can be crucial for managing the disease. The MS Society UK is supporting research aimed at identifying individuals at higher risk of developing MS by analyzing data from the period before clinical onset of typical symptoms.