title: Quantitative analysis of progressive removal of nasal structures during endoscopic suprasellar approach.
abstract: OBJECTIVE
  Following recent studies measuring working area and surgical freedom of transcranial approaches, we aimed to quantify the gain achieved with progressive removal of nasal structures during the endoscopic endonasal suprasellar approach.
  
  
  METHODS
  Human cadaveric anatomic study.
  
  
  METHODS
  The width of the endoscopic endonasal corridor to the suprasellar area was obtained and measured in five cadaver heads using a computerized tracking system with six steps: 1) standard approach with monolateral lateralization of middle turbinate; 2) standard bilateral lateralization of the middle turbinates; 3) monolateral middle turbinectomy; 4) bilateral middle turbinectomy; 5) monolateral ethmoidectomy; 6) bilateral ethmoidectomy.
  
  
  RESULTS
  The progressive removal of nasal structures offers a nonlinear increasing of the working area during the first steps of the procedure. The maximum advantage is offered by bilateral lateralization of the middle turbinates (102.7% increase in exposure), whereas a moderate increase is observed with each following step. Surgical freedom mainly increased during the first part of the approach, that is, with a monolateral right middle turbinectomy (17.9% raise of maneuverability), whereas additional steps did not increase surgical freedom enough to justify an aggressive nasal disruption.
  
  
  CONCLUSIONS
  Monolateral turbinectomy on the side of endoscope docking represents the best solution, optimizing working area and surgical freedom (offering increases of 116.9% and 17.9%, respectively). Bilateral turbinectomy, together with a monolateral anterior and posterior ethmoidectomy, can be reserved for selected cases (increases of 148.5% and 24.7%, respectively). Bilateral ethmoidectomy does not significantly improve surgical freedom (0.81%).
  
  
  METHODS
  N/A. Laryngoscope 124:2231-2237, 2014.
authors.affiliation: Department of Neurosurgery, Hospital Clinic, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain; Department of Human Anatomy and Embryology, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Matteo
authors.initials: M
authors.lastname: de Notaris
authors.forename: Alberto
authors.initials: A
authors.lastname: Prats-Galino
authors.forename: Joaquim
authors.initials: J
authors.lastname: Enseñat
authors.forename: Thomas
authors.initials: T
authors.lastname: Topczewski
authors.forename: Enrique
authors.initials: E
authors.lastname: Ferrer
authors.forename: Luigi Maria
authors.initials: LM
authors.lastname: Cavallo
authors.forename: Paolo
authors.initials: P
authors.lastname: Cappabianca
authors.forename: Domenico
authors.initials: D
authors.lastname: Solari
mesh_terms: D002102:Cadaver; D004724:Endoscopy / Q000379:methods*; D006801:Humans; D019635:Neurosurgical Procedures / Q000379:methods*; D009666:Nose / Q000601:surgery*; D014420:Turbinates / Q000601:surgery*
keywords: Anatomy; endonasal; endoscopic; quantitative; transsphenoidal