ICTAL CONTRALATERAL PARESIS IN COMPLEX PARTIAL SEIZURES

Certain behaviors that occur during a complex partial seizure (CPS) ar e useful in lateralizing the side of seizure onset. In 5 (5.3%) of 94 consecutive patients with partial epilepsy, we observed ictal unilater al arm and hand paresis during 27 of 34 CPS. In all these seizures, th is behavior occurred contralateral to an epileptogenic temporal lobe, as determined by video-EEG monitoring and surgical outcome. In 5 of th e 27 seizures, an observer demonstrated that the paretic arm and hand were flaccid. None of these patients had postictal (Todd's) paralysis. In most of the seizures, the arm ipsilateral to seizure onset had sim ultaneous purposeful movements or automatisms, sometimes with awkward posturing. Ictal unilateral pare sis is distinctly different from icta l dystonia or postictal paralysis and consistently lateralizes seizure onset to the contralateral temporal lobe. Recognition of this particu lar ictal behavior and comparison to other simultaneous behaviors can aid in the lateralization and possibly localization of the epileptogen ic zone.