ASYMMETRIC SPASMS IN WEST SYNDROME

We studied 6 patients with asymmetric spasms who comprised 16.2% of 37 patients with West syndrome (WS) who demonstrated clusters of tonic s pasms on simultaneous video-EEG recordings. Neuroimaging studies showe d diffuse cerebral abnormalities in 3 of 6 patients and unilateral hem ispheric lesions in the remaining 3. In 3, the clusters of spasms occu rred soon after a preceding partial seizure. Lateral dominance of seiz ures alternated in each patient, and the dominant side of the spasms a lso varied in relation to the preceding partial seizures. In the remai ning 3, tonic spasms were constantly dominant on the side contralatera l to the hemispheric lesions. In most of these 6 patients, the seizure s were intractable and psychomotor outcome was poor. In particular, 3 patients had severe psychomotor retardation. These results lend suppor t to the notion that cerebral cortex plays an important role in genera ting clusters of tonic spasms.