brain, spinal cord, and nerve disorders
Multiple Sclerosis (MS)
Introduction
In multiple sclerosis, patches of myelin (the substance that covers most nerve fibers) and underlying nerve fibers in the brain, optic nerves, and spinal cord are damaged or destroyed. The cause is unknown but may involve an attack by the immune system against the body’s own tissues (autoimmune reaction). In most people with multiple sclerosis, periods of relatively good health alternate with episodes of worsening symptoms, but over time, multiple sclerosis gradually worsens. People may have vision problems and abnormal sensations, and movements may be weak and clumsy. Usually, doctors diagnose multiple sclerosis based on symptoms and results of a physical examination and magnetic resonance imaging. Treatment includes corticosteroids, medications that help keep the immune system from attacking the myelin sheath, and medications to relieve symptoms. Life span is unaffected unless the disorder is very severe. The term “multiple sclerosis” refers to the many areas of scarring (sclerosis) that result from destruction of the tissues that wrap around nerves (myelin sheath) in the brain and spinal cord. This destruction is called Overview of Demyelinating Disorders . Sometimes the nerve fibers that send messages (axons) are also damaged. Over time, the brain may shrink in size because axons are destroyed. World wide, about 2.8 million people have multiple sclerosis, and about 107,000 people are diagnosed with multiple sclerosis each year. Most commonly, multiple sclerosis begins between the ages of 20 and 40, but it can begin anytime between ages 15 and 60 years. It is somewhat more common among women. Multiple sclerosis is uncommon among children. Most people with multiple sclerosis have periods of relatively good health (remissions) alternating with periods of worsening symptoms (flare-ups or relapses). Relapses can be mild or debilitating. Recovery during remission is good but often incomplete. Thus, multiple sclerosis worsens slowly over time. 