Abstracts

Rationale: Section of corpus callosum disrupts inter-hemispheric propagation of epileptic activities generating tonic, atonic or gecondarily generalized seizures. Corpus callosotomy is usually aimed to alleviate, but not to achieve total control of, epileptic seizures. We experienced a small fraction of seizure free patients after callosotomy. The purpose of this study is to investigate any clinical factors for long-term seizure remission after total corpus callosotomy in patients with pediatric-onset intractable epilepsy. Methods: The study included 13 consecutive patients with infantile or early childhood onset epilepsy who received one-stage total corpus callosotomy for alleviation of seizures. The age at surgery was ranged from 1 year 5 month to 24 years. All patients were diagnosed as West syndrome at the onset of disease except one with Lennox-Gastaut syndrome. All suffered from tonic or atonic seizures and seizure-related drop episodes. The association between post-operative seizure freedom and pre-operative findings including age at surgery, MRI, and EEG was evaluated. Results: ost-operative seizure freedom was achieved in 4 of 13 patients at least for one year. All of the 4 patients had normal MRI pre-operatively. None of the 5 patients with focal structural lesion, 6 patients with known etiology of epilepsy or 4 patients aged 10 years or older at surgery achieved seizure freedom. Of 7 patients with focal EEG abnormalities, only one became seizure free. Normal MRI was associated with post-operative seizure freedom with statistical significance (p < 0.01). Conclusions: In spite of small number of subjects, this study suggests that a subgroup of patients with infantile or early-childhood onset epilepsy is remarkably responsive to corpus callosotomy. Especially, normal MRI is associated with post-operative seizure freedom.