title: Endoscopic endonasal skull base approach for parasellar lesions: Initial experiences, results, efficacy, and complications.
abstract: BACKGROUND
  Endoscopic surgery is suitable for the transsphenoidal approach; it is minimally invasive and provides a well-lit operative field. The endoscopic skull base approach through the large opening of the sphenoid sinus through both nostrils has extended the surgical indication for various skull base lesions. In this study, we describe the efficacy and complications associated with the endoscopic skull base approach for extra- or intradural parasellar lesions based on our experiences.
  
  
  METHODS
  Seventy-four cases were treated by an endoscopic skull base approach. The indications for these procedures included 55 anterior extended approaches, 10 clival approaches, and 9 cavernous approaches. The operations were performed through both the nostrils using a rigid endoscope. After tumor removal, the skull base was reconstructed by a multilayered method using a polyglactin acid (PGA) sheet.
  
  
  RESULTS
  Gross total resection was achieved in 82% of pituitary adenomas, 68.8% of meningiomas, and 60% of craniopharyngiomas in anterior extended approach and in 83.3% of chordomas in clival approach, but only in 50% of the tumors in cavernous approach. Tumor consistency, adhesion, and/or extension were significant limitations. Visual function improvements were achieved in 37 of 41 (90.2%) cases. Cerebrospinal fluid (CSF) leakage (9.5%), infections (5.4%), neural injuries (4.1%), and vascular injuries (2.7%) were the major complications.
  
  
  CONCLUSIONS
  Our experiences show that the endoscopic skull base approach is a safe and effective procedure for various parasellar lesions. Selection of patients who are unlikely to develop complications seems to be an important factor for procedure efficacy and good outcome.
authors.affiliation: Department of Neurosurgery, Faculty of Life Sciences Research, Kumamoto University Graduate School, Kumamoto, Japan.
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Yano
authors.affiliation: Department of Neurosurgery, Faculty of Life Sciences Research, Kumamoto University Graduate School, Kumamoto, Japan.
authors.forename: Takuichiro
authors.initials: T
authors.lastname: Hide
authors.affiliation: Department of Neurosurgery, Faculty of Life Sciences Research, Kumamoto University Graduate School, Kumamoto, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Shinojima
authors.affiliation: Department of Pharmacology and Molecular Therapeutics, Faculty of Life Sciences Research, Kumamoto University Graduate School, Kumamoto, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hasegawa
authors.affiliation: Department of Neurosurgery, Faculty of Life Sciences Research, Kumamoto University Graduate School, Kumamoto, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kawano
authors.affiliation: Department of Neurosurgery, Faculty of Life Sciences Research, Kumamoto University Graduate School, Kumamoto, Japan.
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Kuratsu
keywords: Endonasal; endoscopic surgery; skull base; transsphenoidal approach