Transcondylar Fossa Approach for Resection of Anterolateral Foramen Magnum Meningioma: 2-Dimensional Operative Video

Abstract

Among the posterolateral corridors to the ventral foramen magnum (FM), the transcondylar fossa (supracondylar transjugular tubercle) approach (TCFA) is indicated for lesions lying anteriorly to the dentate ligament and above the jugular foramen and hypoglossal canal.^1-13 It involves the drilling of the condylar fossa, namely the exocranial surface of the jugular tubercle. Despite the anatomic variability of the condyle and posterior condylar emissary vein,^14,15 they are important landmarks for the TCFA. The extradural jugular tuberculectomy has no risk of iatrogenic mechanical instability compared with the transcondylar approach. This 2-dimensional operative video (Video 1) aims to show the key technical aspects of the TCFA through the case description of an anterolateral FM meningioma. A 35-year-old male patient with a left anterolateral FM meningioma underwent TCFA in a semisitting position. Drilling of the condylar fossa led to an extradural resection of the jugular tubercle. Posterior condylar emissary veins connecting the sigmoid sinus/jugular bulb with the vertebral venous plexus marked the lateral limit of the approach. Through a suprahypoglossal working corridor, the meningioma was debulked and dissected. Postoperative magnetic resonance imaging confirmed complete resection of the tumor, and the patient was discharged neurologically intact on the third postoperative day. TCFA is a valuable technical option for selected anterolateral FM meningiomas. The perfect knowledge and intraoperative use of specific anatomic landmarks are critical to safely perform the TCFA while maximizing the exposure of the surgical target and decreasing the risk of postoperative mechanical instability of the craniovertebral junction.

Keywords: Condylar fossa; Foramen magnum meningioma; Jugular tubercle; Occipital condyle; Posterior condylar emissary vein; Transcondylar approach.