Two children, aged 3 years, with hemisomatic spasms caused by tumors in the ipsilateral cerebellopontine angle are reported from the Division of Pediatric Neurology and Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX. Patient 1 had persistent hemifacial spasms with onset soon after birth; some were complicated by flexion of the arm and extension of the leg. An initial diagnosis of partial seizures was not confirmed by video-EEG monitor, and anticonvulsants were of no benefit. CT and ultrasound were normal, but MRI revealed a C-P angle tumor. Following partial resection of a low-grade ganglioneuroma, the spasms were less severe. Patient 2 developed left sided jerks at 2 years of age, turning of the head to the right, and flexion of left elbow and hip, without loss of consciousness. Movements were worse while speaking or watching television. The EEG was normal and carbamazepine without benefit. MRI uncovered a left sided angle tumor, and spasms ceased after partial resection of a ganglioneuroma. 
COMMENT. The absence of impaired consciousness, normal EEG, and lack of response to antiepileptic drugs should help to distinguish hemifacial or hemisomatic spasms from partial epilepsy and lead to confirmation of a posterior fossa tumor by MRI.