title: Combined Endoscopic Transoral and Endonasal Approach to the Jugular Foramen: A Multiportal Expanded Access to the Clivus.
abstract: BACKGROUND
  The expanded endoscopic endonasal ("far medial") approach to the inferior clivus provides a unique surgical corridor to the ventral surface of the pontomedullary and cervicomedullary junctions. However, exposing neoplasms involving the jugular foramen (JF) through this approach requires extensive nasopharyngeal resection and lateral dissection beyond the boundaries of the endonasal corridor, limiting the extent of resection and restricting to use of this approach to expert surgeons. Here we describe a multiportal endoscopic transoral and endonasal approach to maximize surgical access to the JF and clivus.
  
  
  METHODS
  A multiportal endoscopic transoral and endoscopic approach to the JF and lower clivus was simulated in 8 specimens. A transoral corridor was created through a soft palate incision. The JF and parapharyngeal space were dissected through the transoral trajectory under endoscopic endonasal view. The length of the corridor of the transnasal and transoral trajectories was measured.
  
  
  RESULTS
  The JF was exposed intracranially and extracranially. The exposure extended superiorly to the sphenoid floor, inferiorly to the anterior atlanto-occipital space, and laterally to the internal acoustic meatus and parapharyngeal space. The cisternal parts of the cranial nerves VII-XII and C1 nerve bundles were accessible. Exposure of the JF contents and parapharyngeal space was possible using straight scopes, without Eustachian tube resection. The working corridor to the JF was significantly shorter through the mouth than through the nose (P < 0.0001).
  
  
  CONCLUSIONS
  This approach provides access to the JF from a ventromedial trajectory, enabling panoramic views, and outlines an expanded surgical exposure (superolateral intradural and inferolateral extracranial). It may provide optimal access for resection of dumbbell-shaped lesions of the JF.
authors.affiliation: Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA; Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA; Department of Neurosurgery, Beijing Bo'ai Hospital, China Rehabilitation Research Center, Beijing, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA; Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA.
authors.forename: Halima
authors.initials: H
authors.lastname: Tabani
authors.affiliation: Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA; Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: El-Sayed
authors.affiliation: Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA; Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA.
authors.forename: Ali Tayebi
authors.initials: AT
authors.lastname: Meybodi
authors.affiliation: Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA; Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA.
authors.forename: Dylan
authors.initials: D
authors.lastname: Griswold
authors.affiliation: Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA; Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA.
authors.forename: Praveen
authors.initials: P
authors.lastname: Mummaneni
authors.affiliation: Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA; Skull Base and Cerebrovascular Laboratory, University of California San Francisco, San Francisco, California, USA. Electronic address: arnaubenet@gmail.com.
authors.forename: Arnau
authors.initials: A
authors.lastname: Benet
mesh_terms: D002102:Cadaver; D003388:Cranial Fossa, Posterior / Q000601:surgery*; D004210:Dissection / Q000379:methods*; D006801:Humans; D009055:Mouth; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D044583:Neuroendoscopy / Q000379:methods*; D009666:Nose; D009777:Occipital Bone; D010579:Petrous Bone; D019291:Skull Base
keywords: Expanded endoscopic endonasal approach; Far-medial approach; Jugular foramen; Skull base; Transoral approach