CALLOSOTOMY IN WEST SYNDROME SUGGESTS A CORTICAL ORIGIN OF HYPSARRHYTHMIA

Hypsarrhythmia and spasms of West syndrome have been postulated by som e investigators to have a brainstem origin. Cortical involvement is al so postulated because of the frequent association with cortical lesion s. Cortical discharges have been proposed to stimulate subcortical str uctures (i.e., brainstem) and hypsarrhythmia is a secondarily generali zed phenomenon produced by the brainstem. Two children with cryptogeni c West syndrome refractory for several years to steroids and conventio nal antiepileptic drugs underwent total callosotomy. Hypsarrhythmia th at was bilateral before operation became unilateral after the procedur e and spasms became asymmetrical, suggesting that a corticocortical pa thway through the corpus callosum is important in the generalization o f hypsarrhythmia.