Evaluation of periodic slow head nodding seizure

[Introduction] Head nodding is a phenotype of epileptic seizures such as tonic spasms, atonic seizures, and myoclonus. We may experience a series of cases in which seizures that slowly bend the head forward are presented as a series of cases. These seizure types and clinical course are different from any of the case groups with known head forward bending seizures. [Subjects and Methods] Ten cases of epilepsy with seizures in which the head flexes slowly; frontal lobe epilepsy with myoclonus-like frontal seizures; severe infant myoclonus epilepsy; We compared the video electroencephalogram (EEG) with the clinical course. [Results] In all cases, seizures were series-forming, and no interstitial EEG revealed hypsarrhythmia in all patients. The age of onset in the 10 patients with seizures in which the head was flexed slowly was 3 to 6 months to 5 years. The seizures were repeated every 2.5–50 seconds and one series lasted for 5–20 minutes. EEG at the time of seizure showed asynchronous negative, positive and negative high amplitude slow waves in spasm, and muscle contraction was about 1 second. Low-to high-amplitude slow waves were observed predominantly in the frontal region, and persistent muscle contraction was observed on the posterior neck electromyogram. Intellectual and developmental disabilities were coexisted in all patients. The seizure was intractable with antiepileptic drugs, but corpus callosotomy was effective. [Discussion] The seizure focus was the frontal lobe. The seizure mechanism was similar to tonic spasms in West syndrome in terms of the formation of a series.
Keywords: epilepsy, video-EEG, West syndrome, head nodding