A case of refractory generalized atonic seizure and hemifacial spasm with the possible causative pontocerebellar lesion

Abstract

The patient was a 35-year-old woman. At the age of 1, she had undergone resection and radiation therapy for neoplastic lesions in the pons. She had a history of gelastic seizures when she was in elementary school, and brief lapses of the neck and truncal muscular tone and convulsions on the left face occurred at the age of 23. After a generalized sharp wave in the ictal electroencephalogram and electromyogram recording, left orbicularis oris muscle contraction was observed followed by sudden cervical extensor atonia. Seizure propagation was noted in the cerebral cortex, left facial nerve nucleus, and brainstem reticular formation. In a simultaneous electroencephalography with functional MRI, the blood oxygen level-dependent effect related to generalized sharp waves was observed in the vicinity of brainstem lesions in addition to a decrease in bilateral frontal and parietal lobes signals, as detected in generalized seizures. These findings suggest that the lesion could be a part of the epilepsy network. Although most epileptic seizures are derived from the cerebral cortex, it is important to note that brainstem lesions are involved in seizures in the patient presented in this study.