title: Endoscopic endonasal posterior clinoidectomy.
abstract: BACKGROUND
  Posterior clinoidectomy is a useful procedure for maximizing exposure to the interpeduncular cistern via transcranial approaches for basilar tip aneurysms and select intracranial tumors. The value of posterior clinoidectomy during endonasal endoscopic transclival surgery is not well described.
  
  
  METHODS
  We performed endoscopic endonasal transsphenoidal extradural bilateral posterior clinoidectomy and dorsum sella removal on five silicon-injected cadaveric heads. The dorsum sella was split in the midline and removed from medial to lateral until the posterior clinoids were encountered. The posterior clinoid was dissected from the medial wall of the cavernous sinus and mobilized medially in order to detach it from the ligaments and carefully fractured it from the bony attachment to the petrous apex and carotid canal. Following this, the clival and dorsum sella dura was opened to expose the interpeduncular cistern and its contents.
  
  
  RESULTS
  The technical feasibility of endoscopic endonasal extradural posterior clinoidectomy was reproduced in all five cadaveric specimens. This technique was performed without damaging the vital structures, including preservation of the pituitary gland. After performing bilateral posterior clinoidectomy, the retrosellar dura was opened, allowing good visualization of the contents of the prepontine and interpeduncular cistern.
  
  
  CONCLUSIONS
  We describe the technique of endoscopic endonasal extradural posterior clinoidectomy. We believe this approach is best suited for retrosellar pathology located in the interpeduncular cistern and is a useful adjunct to the transclival approach to increase the field of view and maximize the extent of resection.
authors: Department of Neurosurgery, New York Presbyterian Hospital, Weill Medical College of Cornell University, New York.
authors: Danilo
authors: D
authors: Silva
authors: Moshe
authors: M
authors: Attia
authors: Jothy
authors: J
authors: Kandasamy
authors: Marjan
authors: M
authors: Alimi
authors: Vijay K
authors: VK
authors: Anand
authors: Theodore H
authors: TH
authors: Schwartz