Complete remission of seizures after corpus callosotomy
Corpus callosotomy is usually intended to alleviate-not to achieve total control of-epileptic seizures. A few patients experience complete seizure control after callosotomy, but the associated clinical factors are unknown. The object of this study was to investigate clinical factors associated with long-term seizure remission after total corpus callosotomy in patients with infantile or early childhood onset epilepsy. Thirteen consecutive patients with infantile or early childhood onset epilepsy underwent 1-stage total corpus callosotomy for alleviation of seizures. Their age at surgery ranged from 1 year and 5 months to 24 years (median 7 years). Eleven patients had West syndrome at the onset of disease, and the other 2 had Lennox-Gastaut syndrome. All patients suffered from spasms, axial tonic seizures, or atonic seizures. Six patients had proven etiology of epilepsy, including tuberous sclerosis, polymicrogyria, trauma, and Smith-Magenis syndrome. The association between postoperative seizure freedom and preoperative factors including age at surgery, no MRI abnormalities, proven etiology, and focal electroencephalographic epileptiform discharges was examined. Postoperative seizure freedom was achieved in 4 of 13 patients for a minimum of 12 months. All 4 patients had no MRI abnormalities and no identified etiology. None of the 8 patients with MRI abnormality, 6 patients with known etiology of epilepsy, or 4 patients aged older than 10 years at surgery achieved seizure freedom. Two of the 7 patients with focal electroencephalographic abnormalities became seizure free. Absence of MRI abnormalities was significantly associated with postoperative seizure freedom (p < 0.01). Complete seizure remission is achieved after total corpus callosotomy in a subgroup of patients with intractable epilepsy following West syndrome or Lennox-Gastaut syndrome. One-stage total corpus callosotomy at a young age may provide a higher rate of seizure freedom, especially for patients with no MRI abnormalities and no identified etiology of epilepsy.