Multiple Sclerosis (MS) is a neurological disease that affects both the brain and the spinal cord.

It (MS) damages the myelin sheath, the material that surrounds and protects your nerve cells. This damage slows down or blocks messages between your brain and your body, leading to the symptoms of MS.

No one knows what causes MS. It may be an autoimmune disease, which happens when your body attacks itself. multiple sclerosis affects woman more than men. It often begins between the ages of 20 and 40.

Usually, the disease is mild, but some people lose the ability to write, speak or walk. There is no cure for MS, but medicines may slow it down and help control symptoms. Physical and occupational therapy may also help.

Brain shrinkage is a characteristic of the progression of multiple sclerosis that can only be detected by a magnetic resonance imaging (MRI) - a very costly procedure.

MRI, aside from being expensive and uncomfortable, is often misleading since brain inflammation - also a symptom of the disease - can skew brain volume readings.

Also, the brain begins shrinking relatively late in the progression of the disease, so MRI isn't as good at detecting the disease in its early stages when treatments are most effective.

Now, according to a Johns Hopkins-based study, a five-minute eye exam might prove to be an inexpensive and effective way to gauge and track multiple sclerosis.

Said Johns Hopkins neurologist Peter Calabresi, M.D. and lead author of the study:

"This is an encouraging result. MRI is an imperfect tool that measures the result of many types of tissue loss rather than specifically nerve damage itself. With OCT we can see exactly how healthy these nerves are, potentially in advance of other symptoms.

In addition, OCT scans take roughly one-tenth as long and cost one-tenth as much as the MRI, which means they are faster and cheaper to use in studies that track the effectiveness of new treatments for MS.

The process is called optical coherence tomography (OCT) that will scan the layers of nerve fibers of the retina in the back of the eye, which become the optic nerve. OCT scans look directly at the thickness (and therefore health) of the optic nerve.

The optic nerve is affected early on in the disease, often before the patient suffers permanent brain damage.

Findings appear in the October 2007 issue of Neurology.

Find more details from Science Daily.