title: Comparison of the exposure obtained by endoscope and microscope in the extended trans-sphenoidal approach.
abstract: OBJECTIVE
  Trans-sphenoidal surgery is often combined with other approaches for the treatment of middle cranial base tumors. By combining a maxillotomy with trans-sphenoidal approach, significantly wider exposure to these regions is gained. However, endoscope-assisted techniques have also been used for sellar and parasellar and upper clival regions.
  
  
  METHODS
  An extended trans-sphenoidal approach was performed on 10 cadaver heads using the operating microscope and was repeated with a 0-degree endoscope. The mean horizontal and vertical distances were measured and pictured for each technique, and both distances were compared using a parametric paired Student's t-test.
  
  
  RESULTS
  The mean horizontal distances in the 10 specimens were 19.5 +/- 1.8 mm by microscope and 27.5 +/- 2.2 mm by endoscope, and the mean vertical distances were 25.8 +/- 1.9 mm by the microscope and 34.5 +/- 3.5 mm by the endoscope.
  
  
  CONCLUSIONS
  The aim of this study was to quantify the amount of exposure obtained with an extended trans-sphenoidal approach and to compare both endoscopic and microscopic techniques. Using the endoscope in conjunction with the operating microscope may provide additional exposure and better access in skull base surgery.
authors.forename: Funda
authors.initials: F
authors.lastname: Batay
authors.forename: Emre
authors.initials: E
authors.lastname: Vural
authors.forename: Aykut
authors.initials: A
authors.lastname: Karasu
authors.forename: Ossama
authors.initials: O
authors.lastname: Al-Mefty