Corpus callosotomy and hemispherotomy are conventionally performed via a large craniotomy with the aid of a microscope for children with intractable epilepsy. Primary technical considerations include completeness of disconnection and blood loss. The authors describe an endoscopic technique performed through a microcraniotomy for these procedures.
Four patients with drop attacks and 2 with intractable seizures related to a neonatal stroke underwent endoscopic complete corpus callosotomy and hemispherotomy, respectively. The surgeries were performed through a 2- to 3-cm precoronal microcraniotomy. Interhemispheric dissection to the corpus callosum was done using the standard technique. Subsequently, the bimanual technique with a suction device mounted on an endoscope was used to perform a complete corpus callosotomy, including interforniceal and anterior commissure disconnection. In patients who had hemispherotomy, the fornix was resected posteriorly and lateral disconnection was done by unroofing the temporal horn. Anteriorly, endoscopic corticectomy was done along the ipsilateral anterior cerebral artery to reach the bifurcation of the internal carotid artery to complete the anterior disconnection. Postoperative MRI and diffusion tensor imaging (DTI) of the brain were performed to confirm complete disconnection.
The procedure was accomplished successfully in all patients, with excellent visualization secured. None of the patients required a blood transfusion. Postoperative MRI and DTI confirmed completeness of the disconnection. Patients who underwent corpus callosotomy had complete resolution of drop attacks at a mean follow-up of 6 months, and patients who underwent hemispherotomy became seizure free.
Endoscopic corpus callosotomy and hemispherotomy are surgically feasible procedures associated with minimal blood loss, minimal risk, and excellent visualization.