title: The value of intraoperative sonography in low grade glioma surgery.
abstract: OBJECTIVE
  There is a number of different methods to localize a glioma intraoperatively. Neuronavigation, intraoperative MRI, 5-aminolevulinic acid, as well as intraoperative sonography. Every method has its advantages and disadvantages. Low grade gliomas do not show a specific signal with 5-aminolevulinic acid and are difficult to distinguish macroscopically from normal tissue. In the present study we stress out the importance of intraoperative diagnostic ultrasound for localization of low grade gliomas.
  
  
  METHODS
  We retrospectively evaluated the charts and MRIs of 34 patients with low grade gliomas operated in our department from 2011 until December 2014. The efficacy of ultrasound as an intraoperative navigational tool was assessed. In 15 patients ultrasound was used and in 19 not. Only histologically proven low grades gliomas (astrocytomas grade II) were evaluated.
  
  
  RESULTS
  In none of the patients where ultrasound (combined with neuronavigation) was used (N=15) to find the tumors, the target was missed, whereas the exclusive use of neuronavigation missed the target in 5 of 19 cases of small subcortical low grade gliomas.
  
  
  CONCLUSIONS
  Intraoperative ultrasound is an excellent tool in localizing low grade gliomas intraoperatively. It is an inexpensive, real time neuronavigational tool, which overcomes brain shift. Even when identifying the tumors with ultrasound is very reliable, the extend of resection and the decision to remove any residual tumor with the help of ultrasound is at the moment unreliable.
authors.affiliation: Wedau Kliniken Duisburg, Sana Konzern, Department of Neurosurgery, Duisburg, Germany. Electronic address: opticdisc@aol.com.
authors.forename: Athanasios K
authors.initials: AK
authors.lastname: Petridis
authors.affiliation: Wedau Kliniken Duisburg, Sana Konzern, Department of Neurosurgery, Duisburg, Germany.
authors.forename: Maxim
authors.initials: M
authors.lastname: Anokhin
authors.affiliation: Wedau Kliniken Duisburg, Sana Konzern, Department of Neurosurgery, Duisburg, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Vavruska
authors.affiliation: Department of Neurosurgery, Clinic of Cologne University of Witten-Herdecke, Duisburg, Germany.
authors.forename: Mehran
authors.initials: M
authors.lastname: Mahvash
authors.affiliation: Wedau Kliniken Duisburg, Sana Konzern, Department of Neurosurgery, Duisburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Scholz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000000981:diagnostic imaging* / Q000601:surgery*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000592:standards*; D019635:Neurosurgical Procedures / Q000592:standards*; D012189:Retrospective Studies; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional / Q000592:standards*; D055815:Young Adult
keywords: Intraoperative sonography; Low grade glioma; Neuronavigation