P-5-573 - Cysts of the anterior third ventricle: Surgical treatment

Abstract

Endoscopic approaches for third ventricular tumors, both transcortical and transcallosal approaches, are described. A 4-mm diameter, 0-degree rod-lens endoscope is used in both procedures, and angled rod-lens endoscopes are used for angled views. The transcortical transventricular approach is made via a burr hole placed at the nondominant frontal area, 1-inch lateral to the midline along the coronal suture. A folded vinyl tube, which can be expandable to a 1-cm tube by unfolding, is placed into the lateral ventricle toward the tumor under an image-guidance system. The transcallosal approach is made via a burr hole placed along the lateral margin of the superior sagittal sinus at the nondominant frontal area. The surgical corridor is made along the interhemispheric fissure. A rolled, cigarette-shaped, cotton patty is placed anteriorly and posteriorly along the surgical trajectory to keep the corridor open. The corpus callosum is opened, and the tumor is removed with surgical instruments inserted through the supported corridor parallel with the endoscope, which is mounted to an endoscope holder. Endoscopic transcortical and transcallosal approaches for the removal of third ventricular tumors are described. Compared with endoscopy performed through fixed working-channels, these techniques increase flexibility for surgeons to maneuver surgical instruments for delicate microdissection and tumor removal.