HEMIPARESIS AND HOMONYMOUS HEMIANOPIA AS THE PRESENTING SIGN OF MULTIPLE-SCLEROSIS

We report two young patients presenting with acute homonymous hemianop ia and acute severe hemiparesis involving the face. The diagnostic wor k-up led to the diagnosis of multiple sclerosis. Clinically symptomati c retrochiasmal demyelinating lesions are rare even in the long-term c ourse of multiple sclerosis and those affecting the pyramidal tract us ually produce only mild partial dysfunction with bilateral symptoms du e to brainstem or spinal cord involvement. Acute homonymous hemianopia or motor hemiparesis first suggest another etiology than multiple scl erosis, particularly a vascular lesion, MRI is the investigation of ch oice in this clinical setting, showing an unusually large lesion in mo st cases where a demyelination is the cause. Clinical recovery neverth eless is usually excellent, despite persistence of the lesion on repea ted imaging, This contrasts with that of an infarction and also with t hat of acute monophasic demyelinating disease (Marburg, Bale), variant s of multiple sclerosis that need to be considered initially.