Background: A 29-year-old male presented with fluctuating but progressive sensory disturbances comprising tingling and dysesthesia in his right leg. MRI of the brain showed white matter lesions initially thought to be caused by multiple sclerosis. Investigations: Neurological examination, cerebrospinal fluid examination, laboratory blood testing, brain and spinal MRI scans. Diagnosis: Spinal cord schwannoma. Management: Surgical removal of the schwannoma. An algorithm is provided that clarifies the appropriate MRI work-up for cases where the clinical presentation is suggestive of multiple sclerosis.