Overnight polygraphic study of agenesis of the corpus callosum with seizures resembling infantile spasms

Abstract

In a 4-month-old female with agenesis of the corpus callosum, seizures resembling infantile spasms were observed succeeding tonic-clonic seizures. Interictal EEG revealed hypsarrhythmia with an asynchronous pattern. Overnight sleep polygraphy was performed before, during and after ACTH therapy. The results were as follows: 1) Clinical seizures were observed only before ACTH therapy. The clinical seizures and the ictal discharges without any apparent clinical seizures occurred in all stages of wakefulness, REM sleep and NREM sleep. 2) The clinical seizures first began with the tonic-clonic seizures and were followed by seizures resembling infantile spasms. The seizures resembling infantile spasms did not appear singly. The ictal discharges in the tonic-clonic seizures appeared only in one hemisphere and, moreover, asynchronously on many occasions. The polygram of a seizure resembling infantile spasms was just like that of infantile spasms. 3) Before ACTH therapy, decrease of REM sleep time and lack of slow wave sleep were found. Decrease of REM sleep time, lightening of sleep and prolongation of awake time were observed during ACTH therapy as compared with those before the therapy. It was indicated that the seizures resembling infantile spasms in the present case differed considerably from infantile spasms. In addition, it was suggested that the asynchrony of hypsarrhythmia and the asymmetry of ictal discharges were not attributable to agenesis of the corpus callosum but dysfunction of a lower area than the corpus callosum.