What is the best test to confirm suspected multiple sclerosis?

• A. Brain biopsy
• B. Computed tomography
• C. Lumbar puncture
• D. Magnetic resonance imaging

Answer: (D)

Multiple sclerosis is diagnosed by demonstrating demyelinating lesions that appear in different places within the central nervous system and at different times. Magnetic resonance imaging shines here because it is highly sensitive for detecting the characteristic MS plaques in the brain and spinal cord. With MRI, you can see typical lesion locations—periventricular, juxtacortical, infratentorial areas, and along the spinal cord—and how they evolve over time. When gadolinium is used, active inflammation lights up, helping to show ongoing disease. Taken together, these imaging findings support proving dissemination in space and time, which is central to confirming MS under diagnostic criteria.

Other tests have roles that are more supportive than definitive. A brain biopsy is invasive and rarely needed because MRI already provides clear evidence in most cases. Computed tomography is less sensitive than MRI for detecting MS lesions, especially early or small plaques. A lumbar puncture can reveal oligoclonal bands in the CSF and mild inflammatory changes that support the diagnosis, but these findings are not specific or definitive on their own.