Gamma knife callosotomy in children with drug-resistant epilepsyYoshiyasu Iwai1, Kazuhiro Yamanaka2, Ichiro Kuki3, Shin Okazaki3, Hisashi Kawawaki31Osaka, Japan 2Department of Neurosurgery, Osaka City General Hospital 3Department of Pediatric Neurology, Osaka City General Hospital Keywords: seizures, callosotomy, gamma knife, radiosurgery, epilepsy
Corpus callostomy can be an effective procedure for selected epilepsy patients.
We evaluated the efficacy of gamma knife callosotomy.
Case 1: a 14-year-old female had a history of complex-partial seizure and drop attack from the age of 2 and half years. At the age of 9-years, the patient suffered behavior disturbance. At 14-years old the patient received gamma knife radiosurgery (GKS) for the anterior half of the corpus callosum with a maximum dose of 140 Gy (4 mm collimator,9shots, treatment volume 0.98ml). Case 2: a 5-year-old male. The patient suffered complex seizure from the age of 4 months, and with west syndrome at the age of 5 months. He also suffered drop attack from 3 years old. GKS was performed on the anterior one third of the corpus callosum with a maximum dose of 140 Gy (4mm collimator, 11 shots, treatment volume 1.15ml).
We performed gamma knife callosotomy for two patients with intractable epilepsy associated with tuber sclerosis.
Case 1: After the procedure, drop attacks decreased 25%, urinary incontinence disappeared, and behavior disturbance was improved. 8 to 14 months after GKS, brain edema occurred without symptoms. The patient received a second GKS for the posterior third of the corpus callosum with a maximum dose of 140 Gy (4 mm collimator, 8 shots, treatment volume 0.63ml) 23 months after the first GKS. 1 month after the second GKS, complex-partial seizure was markedly improved and 5 months after, the seizures had almost disappeared.
Case 2: This patient showed no improvement with brain edema at the frontal lobe between 6 to 9 months after GKS. The patient received a second GKS for the posterior one third of the corpus callosum with a maximum dose of 140 Gy (4 mm collimator, 7 shots, treatment volume 0.59 ml) 19 months after the first GKS.
This was a small retrospective series.
Our experiences revealed that the gamma knife callosotomy can be effective for intractable seizure in some patients, but we need further evaluation and long-term follow-up of outcome and complications.
Additional research is necessary to determine the value of radiosurgical callosotomy. Project Roles:
Y. Iwai (), K. Yamanaka (), I. Kuki (), S. Okazaki (), H. Kawawaki ()