29th April 2024

A 35-year-old woman reports a three-month history of intermittent visual disturbances in her right eye, described as a temporary loss of vision.

A 35-year-old woman reports a three-month history of intermittent visual disturbances in her right eye, described as a temporary loss of vision. She also mentions occasional numbness and tingling in her hands and feet, and has experienced two episodes of difficulty in coordinating her movements. Her symptoms seem to resolve partially but then recur. On examination, there is evidence of an afferent pupillary defect in the right eye and mild ataxia. MRI of the brain reveals multiple periventricular lesions.

Which is the most likely diagnosis?