Endoscopic-assisted transcolumellar approach to the clivus: an anatomical study

OBJECTIVE: Surgical exposure of the clivus and retroclival region is a challenging problem. Several extracranial and intracranial approaches using microsurgical techniques have been proposed in the search to optimize the exposure of the clival region. The objective of the present study was to develop an endoseopic-assisted transcolumellar approach to the anterior clivus. STUDY DESIGN: Experimental anatomic study. METHODS: The approach was studied in 10 consecutive cadaveric preparations. It included a preliminary external rhinoplasty technique with a septal displacement procedure, which gives a wide intranasal route to the posterior wall of the nasopharynx. By use of a drill system and instruments specially designed for endoscopic sinus surgery, the clivus and retroclival region were appropriately managed. Direct morphometric measurements were obtained during all steps of the procedure. RESULTS: The endoscopic-assisted transcolumellar approach developed in the present experimental study allowed a good exposure of the clivus area and anterior cranial-cervical junction. By performing a preliminary septoplasty, the nostrils were turned into a single passage with adequate space for endoscopic insertion and manipulation of one or two instruments. The authors were able to completely expose the posterior wall of the sphenoid sinus and clival dura after the thick bone of the vomer, the floor of the sphenoid, and the clivus were removed by a drill. Angled endoscopes provided a comprehensive view of the retrosellar area. CONCLUSIONS: The endoscopic-assisted transcolumellar approach, besides offering a wide opening for endoscopic management of the clivus, also allowed the surgeon to perform a double-handed procedure and to associate the use of a microscope if needed. The use of endoscopes, although lacking the three-dimensional view, gave a thorough and closer exposure of the surgical field with the advantage of a multiangled perspective.