excellent summary howie! i just had an interesting case of a girl with vertigo (specifically, oscillopsia), nausea/vomiting and severe ataxia without tinnitus or nystagmus. MRI showed what appeared like a T2-hyperintense paracentral subcortical lesion, no involvement of the 8th nerve or other focal intensities. Dr. howie, what is the differential diagnosis and what further tests would you do?