Cortical lesions associated with transient neurological symptoms - not always a matter of cause and effect

The occurrence of transient recurrent stereotypical neurological events mandates the exclusion of an underlying brain lesion. When imaging studies demonstrate the presence of a structural brain lesion, a cause and effect relationship between the two entities is assumed, and the decision for surgical intervention may then follow almost automatically. We describe five patients with transient neurological events suspected as being seizures that were referred for surgery because of an associated structural brain lesion. Video electroencephalographic recordings revealed that the events that brought these patients to neurosurgical attention were non-epileptic seizures. None of these patients underwent surgical intervention, and all were referred for behavioral therapy. Therefore, even in the presence of a confirmed brain lesion, the presenting paroxysmal events may be of a non-organic origin and should not necessarily be assumed to be caused by the concomitantly existing structural abnormality.