title: Comparison of navigated 3D ultrasound findings with histopathology in subsequent phases of glioblastoma resection.
abstract: OBJECTIVE
  The purpose of the study was to compare the ability of navigated 3D ultrasound to distinguish tumour and normal brain tissue at the tumour border zone in subsequent phases of resection.
  
  
  METHODS
  Biopsies were sampled in the tumour border zone as seen in the US images before and during surgery. After resection, biopsies were sampled in the resection cavity wall. Histopathology was compared with the surgeon's image findings.
  
  
  RESULTS
  Before resection, the tumour border was delineated by ultrasound with high specificity and sensitivity (both 95%). During resection, ultrasound had acceptable sensitivity (87%), but poor specificity (42%), due to biopsies falsely classified as tumour by the surgeon. After resection, sensitivity was poor (26%), due to tumour or infiltrated tissue in several biopsies deemed normal by ultrasound, but the specificity was acceptable (88%).
  
  
  CONCLUSIONS
  Our study shows that although glioblastomas are well delineated prior to resection, there seem to be overestimation of tumour tissue during resection. After resection tumour remnants and infiltrated brain tissue in the resection cavity wall may be undetected. We believe that the benefits of intraoperative ultrasound outweigh the shortcomings, but users of intraoperative ultrasound should keep the limitations shown in our study in mind.
authors.affiliation: Department of Radiology, St.Olav University Hospital, Trondheim, Norway. ola.rygh@ntnu.no
authors.forename: Ola Morten
authors.initials: OM
authors.lastname: Rygh
authors.forename: Tormod
authors.initials: T
authors.lastname: Selbekk
authors.forename: Sverre Helge
authors.initials: SH
authors.lastname: Torp
authors.forename: Stian
authors.initials: S
authors.lastname: Lydersen
authors.forename: Toril Anita Nagelhus
authors.initials: TA
authors.lastname: Hernes
authors.forename: Geirmund
authors.initials: G
authors.lastname: Unsgaard
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001921:Brain / Q000473:pathology / Q000601:surgery; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D003951:Diagnostic Errors / Q000517:prevention & control / Q000706:statistics & numerical data; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D038361:Neuronavigation / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods; D011237:Predictive Value of Tests; D013238:Stereotaxic Techniques; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*