Asymmetric spasms in west syndrome

Abstract

We studied 6 patients with asymmetric spasms who comprised 16.2% of 37 patients with West syndrome (WS) who demonstrated clusters of tonic spasms on simultaneous video-EEG recordings. Neuroimaging studies showed diffuse cerebral abnormalities in 3 of 6 patients and unilateral hemispheric lesions in the remaining 3. In 3, the clusters of spasms occurred soon after a preceding partial seizure. Lateral dominance of seizures alternated in each patient, and the dominant side of the spasms also varied in relation to the preceding partial seizures. In the remaining 3, tonic spasms were constantly dominant on the side contralateral to the hemispheric lesions. In most of these 6 patients, the seizures were intractable and psychomotor outcome was poor. In particular, 3 patients had severe psychomotor retardation. These results lend support to the notion that cerebral cortex plays an important role in generating clusters of tonic spasms.