Surgical Resection of a Third Ventricle Nongerminomatous Germ Cell Tumor: Two-Dimensional Operative Video

Surgical resection of a pineal tumor growing into the third ventricle is difficult owing to the complex neurovascular structures, and nongerminomatous germ cell tumor is the most common malignant tumor in pediatric patients. Removing the tumor efficiently with minimal blood loss while protecting the surrounding neurovascular structure is challenging. We present a surgical case of a 9-year-old patient with a third ventricle nongerminomatous germ cell tumor (Video). Mass effect of the tumor or acute hydrocephalus is the possible reason for the coma. In this case, the reason of coma may be mass effect of the tumor, not the acute hydrocephalus. Informed consent was obtained from the patient's guardian. Intraoperatively we used a modified right head-up park bench position and a linear incision. The right occipital bone flap was designed to cross the superior sagittal sinus and transverse sinus. The primary surgical approach was the occipital transtentorial approach; an alternative was the supracerebellar infratentorial approach. After cutting the tentorium, a spatula was applied to retract the cerebellum and incised tentorium, with no extra brain retraction on the occipital lobe to minimize visual disturbance. The quadrigeminal cistern was opened, and the tumor was yellowish with heterogeneous consistency. Instead of rushing into the tumor debulking, we paid more attention to devascularization of the tumor from bilateral posterior medial choroidal arteries as much as possible. After debulking using an ultrasound aspirator, the tumor was removed in a piecemeal fashion, and the surgical field was inspected using an endoscope for any residue.