James K. Liu, MD, and Vincent N. Dodson, BS
Department of Neurological Surgery, Center for Cerebrovascular and Skull Base Surgery, Neurological Institute of New Jersey, Rutgers University, New Jersey Medical School, RWJ Barnabas Health, Newark, New Jersey
Fourth ventricular tumors have traditionally been removed via transvermian approaches, which can result in potential dysequilibrium and mutism. The telovelar approach is an excellent alternative to widely expose fourth ventricular tumors without transgressing the cerebellar vermis. This is achieved by opening the cerebellomedullary fissure and incising the tela choroidea and inferior medullary velum, which form the lower half of the roof of the fourth ventricle. In this operative video manuscript, the authors demonstrate microsurgical resection of a fourth ventricular subependymoma arising from the rhomboid fossa via the telovelar approach. The key technical nuance in this video is to demonstrate a gentle and safe technique to identify a dissectable plane to peel the tumor off of the rhomboid fossa using a microspreading technique with fine micro-bayonetted forceps. A gross-total resection was achieved, and the patient was neurologically intact.
**Intro music: "Daybreak" by Graeme Rosner
