title: Expanded endonasal approach: the rostrocaudal axis. Part II. Posterior clinoids to the foramen magnum.
abstract: OBJECTIVE
  Transsphenoidal approaches have been used for a century for the resection of pituitary and other sellar tumors. Recently, however, the standard endonasal approach has been expanded to provide access to other parasellar lesions. With the addition of the endoscope, this expansion has significant potential for the resection of skull base lesions.
  
  
  METHODS
  The anatomical landmarks and surgical techniques used in expanded (extended) endoscopic approaches to the clivus and cervicomedullary junction are reviewed and presented, accompanied by case illustrations of each segment (or module) of approach. The caudal portion of the midline anterior skull base and the cervicomedullary junction is divided into modules of approach: the middle third of the clivus, its lower third, and the cervicomedullary junction. Case illustrations of successful resections of lesions via each module of the approach are presented and discussed.
  
  
  CONCLUSIONS
  Endoscopic expanded endonasal approaches to caudally located midline anterior skull base and cervicomedullary lesions are feasible and hold great potential for decreased morbidity. The effectiveness and appropriate use of these techniques must be evaluated by close examination of outcomes as case series expand.
authors.affiliation: Department of Neurosurgery, Minimally Invasive Neurosurgery Center, Center for Cranial Base Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA. kassamab@upmc.edu
authors.forename: Amin
authors.initials: A
authors.lastname: Kassam
authors.forename: Carl H
authors.initials: CH
authors.lastname: Snyderman
authors.forename: Arlan
authors.initials: A
authors.lastname: Mintz
authors.forename: Paul
authors.initials: P
authors.lastname: Gardner
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Carrau
mesh_terms: D003388:Cranial Fossa, Posterior / Q000601:surgery*; D004724:Endoscopy; D005539:Foramen Magnum / Q000601:surgery*; D006801:Humans; D019635:Neurosurgical Procedures; D019291:Skull Base / Q000601:surgery*; D013101:Sphenoid Sinus / Q000601:surgery