Chapter 16 - Foramen magnum meningiomas

Abstract

The foramen magnum meningioma (FMM) is one of most challenging tumors among all the meningiomas because of its distinctive location, clinical course, insidious onset, and the relative large size of the tumor during presentation. These tumors are slow-growing and clinical symptoms vary according to involvement of different structures including the spinal cord, vertebral artery, lower cranial nerves, and medulla oblongata. Controversies regarding appropriate surgical approach for resection of tumor in this unique location continue. Tumors in the posterior or posterolateral region of the foramen magnum is accessible by midline suboccipital approach. The anterior and anterolateral tumors are encountered by various modifications of the far lateral approach. Drilling of condylar fossa is adequate in most of the cases as tumors often create a surgical corridor. However, an anterior tumor with significant extension on both sides of midline may require variable amounts of condyle resection. Here we review the FMMs with an emphasis on surgical approaches.