Endoscopic, Endonasal, Transsphenoidal, Transclival Approach for Resection of Odontoid Process: 2-Dimensional Operative Video

Osteogenesis imperfecta results in insufficient and/or abnormal collagen production, leading to fragile bone. Patients oftenpresent to neurosurgical care because of axial skeleton involvement.1,2Endonasal odontoidectomy for basilar invagination hasbeen previously reported.3However, a surgical video outlining the technical nuances is lacking. We describe a man in his early 20swith osteogenesis imperfecta type III who presented with a refractory case of basilar invagination with draping of the pons over aretroverted dens, despite previous halo traction and occiput-to-iliumfixation. The patient's debilitating symptoms prompted thedecision to decompress the brainstem. The earlier posteriorapproach appeared to have achieved maximal possible decom-pression andfixation. Furthermore, due to the significant rostral migration of the dens, the traditional transoral or transmaxillaryapproaches were unlikely to offer an adequate operative corridor. Thus, the endoscopic, transsphenoidal, transclival odontoi-dectomy approach was recommended. The patient was positioned supine with the head in 3-pointfixation. Sinusotomy, nasalseptal elevation, and sphenoidotomy were performed. Thefloor of the sphenoid sinus was drilled to expose the lower clivus,which was removed to expose the anterior arch of C1. The inferiorportion of the anterior C1 arch and the underlying portion of thedens were resected to decompress the brainstem. Operative time was 4 hours, with no complications.Postoperatively, the patientexpressed a reduction in spasms and resolution of diplopia and upward gaze, and imaging demonstrated successful brainstemdecompression. The patient consented to undergo the procedure and for the publication of the images. Institutional review boardreview was not sought because a single case report does not meet the minimum criteria for institutional review board review.Usedwith permission from Barrow Neurological Institute, Phoenix, Arizona. Image at Timestamp 03:11 was reproduced/adapted withpermission from the Neurosurgery Research & Education Foundation, Rhoton Collection (R). An Open Access or Creative Commonspublishing model conveys no rights to use this materialin any format without written permission from NREF.