Endonasal Approach to the Craniocervical Junction

Abstract

The transnasal endoscopic approach to the craniocervical junction is used in lesions compressing the medulla posterior. Pathologies include dens invagination in rheumatoid arthritis, deformities such as os odontoideum, or neoplasms such as craniocervical chordomas. In the sagittal plane, generally the base of C2 is the caudal limit. In the coronal plane, the dens can be resected with practically no side effects; resection beyond this carries the risk of damage to the caudal cranial nerve, the carotid and vertebral artery, or the Eustachian tube. If the anterior arch of C1 and the odontoid process are resected in the course of the surgery, this segment gets unstable with the need for dorsal fusion. Since most of the pathologies are extradural, csf leaks are rarely challenging conditions. Technically, this approach is not highly demanding, which allows also the nonextensively experienced transnasal endoscopist to perform this surgery safely.