Diagnosis Methods

In practice, physicians will rule everything else out before diagnosing a patient with MS. Other diseases related to the immune system can mimic symptoms of MS: Lyme disease, Syphilis, HIV, etc.

MRI Scanning

Magnetic resonance imaging (MRI) is a medical examination that takes slices of the brain from three perspectives: sagittal, horizontal, and coronal. From the MRI scan, bright spots or lesions can be visible indicators of multiple sclerosis. These lesions are areas of damaged tissues located in the brain and are more commonly located wherever white matter appears. In the body, white matter can be found in the axon and myelin. Detecting lesions in an MRI scan alone is not enough to diagnose a patient with multiple sclerosis. [6]

The needle is inserted between the third and fourth vertebrae and just deep enough to get past the spinal cord. Under normal conditions, the CSF is clear; any display of color means that something unusual is happening within the body. However, even if a patient has MS, the CSF will remain clear and needs further testing. [8] Due to the nature of multiple sclerosis, the immune system is highly active in the central nervous system and attacking the myelin surrounding the axon. Utilizing gel electrophoresis can help identify a component that is usually characteristic of the immune system: antibodies. Due to the nature of MS, the immune system is comparably more active in the central nervous system, attacking the myelin surrounding the neuron's axon. During gel electrophoresis, the presence of oligoclonal bands indicates the presence of immunoglobulins, an increased amount of antibodies, and possible inflammation in the central nervous system. [6]

Visually Evoked Potential

Lastly, a definitive testing method is to measure the electrical activity in a person's brain. Similar to an EEG, electrodes are placed onto the scalp to measure the patients' brain response to a visual stimulus. If an MRI reveals a lesion in either optic nerve, the next course of action is to look at a visually evoked potential. [source] In the figure to the right, an example of the brain response being measured depicts a graph measuring voltage (mV) versus Time (ms). Comparing the right and left optic nerves during visual stimulation, a delay can be observed. Although this is not a depiction of the action potential being conducted in the brain, the same principles can still be applied. In MS, the demyelination of the axon results in slower conduction of the action potential. And so, the delay in potential seen in the left optic nerve is an indication of a decrease in myelin in the central nervous system. [6]

These three diagnostic methods are not the only ways to test for multiple sclerosis. Other tests, like a blood test, can provide further information about the patient's condition. Alone, each test cannot confirm a MS diagnosis. But together, a physician can more confidently rule out similar autoimmune disorders and give a more accurate diagnosis of MS.