title: Factors affecting postoperative cerebrospinal fluid leaks after retrosigmoidal craniotomy for vestibular schwannomas.
abstract: OBJECTIVE
  The aim of this study was to identify patients likely to develop CSF leaks after vestibular schwannoma surgery using a retrospective analysis for the identification of risk factors.
  
  
  METHODS
  Between January 2001 and December 2006, 420 patients underwent retrosigmoidal microsurgical tumor removal in a standardized procedure. Of these 420 patients, 363 underwent treatment for the first time, and 27 suffered from recurrent tumors. Twenty-six patients had bilateral tumors due to neurofibromatosis Type 2, and 4 patients had previously undergone radiosurgical treatment. An analysis was performed to examine the incidence of postoperative CSF fistulas in all 4 groups.
  
  
  RESULTS
  The incidence of CSF leakage was higher in the tumor recurrence group (11.1%) than in patients undergoing surgery for the first time (4.4%). There were no CSF fistulas in the neurofibromatosis Type 2 group or in patients with preoperative radiosurgical treatment. Tumor size was identified as a possible risk factor in a previous study.
  
  
  CONCLUSIONS
  Surgery for recurrent tumors is a significant risk factor for the development of CSF leaks.
authors.affiliation: Department of Neurosurgery, International Neuroscience Institute, Hannover, Germany. lennart@stieglitze.de
authors.forename: Lennart H
authors.initials: LH
authors.lastname: Stieglitz
authors.forename: Karsten H
authors.initials: KH
authors.lastname: Wrede
authors.forename: Alireza
authors.initials: A
authors.lastname: Gharabaghi
authors.forename: Venelin M
authors.initials: VM
authors.lastname: Gerganov
authors.forename: Amir
authors.initials: A
authors.lastname: Samii
authors.forename: Madjid
authors.initials: M
authors.lastname: Samii
authors.forename: Wolf O
authors.initials: WO
authors.lastname: Luedemann