title: A basic model for training of microscopic and endoscopic transsphenoidal pituitary surgery: the Egghead.
abstract: BACKGROUND
  Transsphenoidal endoscopic surgery has gained popularity in the last 2 decades and is becoming a standard technique for resection of pituitary adenomas. In contrast to their ENT colleagues, neurosurgical residents have practically no endoscopic experience when they reach the training stage for transsphenoidal procedures. We have developed an affordable method for repetitive training in endoscopic (and microscopic) work in a narrow channel, allowing training of the basic movements needed for resection of pituitary adenoma.
  
  
  METHODS
  In collaboration with colleagues in the ENT Department, Cantonal Hospital St. Gall, and the Technical University of Zurich, a three-dimensional model of the nasal cavity was developed and patented. The Egghead model consists of a 3D synthetic reconstruction of the head nasal cavity and sphenoid sinus. A boiled egg represents the sella. For validation, 17 neurosurgical residents from the Department of Neurosurgery, University Hospital of Basel, and Department of Neurosurgery, Cantonal Hospital of St. Gall, St. Gall, Switzerland, and two experts performed a standardized procedure mimicking a transsphenoidal pituitary procedure by dissecting a corridor to the egg yolk and resecting it, respecting the surrounding egg white. This procedure was performed under both microscopic and video-endoscopic visualization. A score for the precision and speed of the surgical performance was developed and used.
  
  
  RESULTS
  The model allows repetitive training of the resection of the egg yolk under sparing of the egg white after careful opening of the shell. The validation data showed a steeper learning curve using the endoscopic technique than performing the same task using the microscope. After three repetitions, the quality of resection was better with the endoscopic technique.
  
  
  CONCLUSIONS
  Our model, the Egghead, is affordable, offers tactile feedback and allows infinite repetitions in basic training for pituitary surgery. It can be used for training of advanced neurosurgical residents, who thus far have very few possibilities of acquiring endoscopic experience.
authors: Department of Neurosurgery, Cantonal Hospital of St. Gall, St. Gall, Switzerland. doortjeengel@gmail.com.|Department of Neurosurgery, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, D-72076, Tuebingen, Germany. doortjeengel@gmail.com.
authors: Doortje C
authors: DC
authors: Engel
authors: Department of Neurosurgery, University Hospital of Basel, Basel, Switzerland.
authors: Andrea
authors: A
authors: Ferrari
authors: Department of ENT, Cantonal Hospital of St. Gall, St. Gall, Switzerland.
authors: Abel-Jan
authors: AJ
authors: Tasman
authors: Inspire® - ETH Zurich, St. Gall, Switzerland.
authors: Raphael
authors: R
authors: Schmid
authors: Inspire® - ETH Zurich, St. Gall, Switzerland.
authors: Ralf
authors: R
authors: Schindel
authors: Clinical Trials Unit, Cantonal Hospital of St. Gall, St. Gall, Switzerland.
authors: Sarah R
authors: SR
authors: Haile
authors: Department of Neurosurgery, University Hospital of Basel, Basel, Switzerland.
authors: Luigi
authors: L
authors: Mariani
authors: Department of Neurosurgery, Cantonal Hospital of St. Gall, St. Gall, Switzerland.
authors: Jean-Yves
authors: JY
authors: Fournier
mesh_terms: D004531:Eggs; D004724:Endoscopy / Q000193:education* / Q000379:methods; D006801:Humans; D019635:Neurosurgical Procedures / Q000193:education* / Q000379:methods; D010902:Pituitary Gland / Q000601:surgery*; D013101:Sphenoid Sinus / Q000601:surgery*
keywords: Endoscopy; Microscopy; Neurosurgery training; Pituitary surgery; Training model