title: Surgically acquired deficits and diffusion weighted MRI changes after glioma resection--a matched case-control study with blinded neuroradiological assessment.
abstract: BACKGROUND
  Acquired deficits following glioma resection may not only occur due to accidental resection of normal brain tissue. The possible importance of ischemic injuries in causing neurological deficits after brain tumor surgery is not much studied. We aimed to study the volume and frequency of early postoperative circulatory changes (i.e. infarctions) detected by diffusion weighted resonance imaging (DWI) in patients with surgically acquired neurological deficits compared to controls.
  
  
  METHODS
  We designed a 1 ∶ 1 matched case-control study in patients with diffuse gliomas (WHO grade II-IV) operated with 3D ultrasound guided resection. 42 consecutive patients with acquired postoperative dysphasia and/or new motor deficits were compared to 42 matched controls without acquired deficits. Controls were matched with respect to histopathology, preoperative tumor volumes, and eloquence of location. Two independent radiologists blinded for clinical status assessed the postoperative DWI findings.
  
  
  RESULTS
  Postoperative peri-tumoral infarctions were more often seen in patients with acquired deficits (63% versus 41%, p = 0.046) and volumes of DWI abnormalities were larger in cases than in controls with median 1.08 cm3 (IQR 0-2.39) versus median 0 cm3 (IQR 0-1.67), p = 0.047. Inter-rater agreement was substantial (67/82, κ = 0.64, p<0.001) for diagnosing radiological significant DWI abnormalities.
  
  
  CONCLUSIONS
  Peri-tumoral infarctions were more common and were larger in patients with acquired deficits after glioma surgery compared to glioma patients without deficits when assessed by early postoperative DWI. Infarctions may be a frequent and underestimated cause of acquired deficits after glioma resection. DWI changes may be an attractive endpoint in brain tumor surgery with both good inter-rater reliability among radiologists and clinical relevance.
authors.affiliation: Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway; MI Lab, Norwegian University of Science and Technology, Trondheim, Norway; National Centre for Ultrasound and Image Guided Therapy, Trondheim, Norway.
authors.forename: Asgeir S
authors.initials: AS
authors.lastname: Jakola
authors.affiliation: Department of Radiology, St. Olavs University Hospital, Trondheim, Norway; Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Erik M
authors.initials: EM
authors.lastname: Berntsen
authors.affiliation: Department of Radiology, St. Olavs University Hospital, Trondheim, Norway.
authors.forename: Pål
authors.initials: P
authors.lastname: Christensen
authors.affiliation: Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway.
authors.forename: Sasha
authors.initials: S
authors.lastname: Gulati
authors.affiliation: Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway; National Centre for Ultrasound and Image Guided Therapy, Trondheim, Norway; Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Geirmund
authors.initials: G
authors.lastname: Unsgård
authors.affiliation: Department of Radiology, St. Olavs University Hospital, Trondheim, Norway; Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Kjell A
authors.initials: KA
authors.lastname: Kvistad
authors.affiliation: Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway; MI Lab, Norwegian University of Science and Technology, Trondheim, Norway; National Centre for Ultrasound and Image Guided Therapy, Trondheim, Norway.
authors.forename: Ole
authors.initials: O
authors.lastname: Solheim
mesh_terms: D000328:Adult; D000368:Aged; D020520:Brain Infarction / Q000175:diagnosis* / Q000209:etiology; D001932:Brain Neoplasms / Q000473:pathology / Q000601:surgery*; D016022:Case-Control Studies; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D005910:Glioma / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D015588:Observer Variation; D011183:Postoperative Complications / Q000209:etiology / Q000473:pathology*; D012189:Retrospective Studies; D016896:Treatment Outcome