title: Multimodal MRI can identify perfusion and metabolic changes in the invasive margin of glioblastomas.
abstract: OBJECTIVE
  To use perfusion and magnetic resonance (MR) spectroscopy to compare the diffusion tensor imaging (DTI)-defined invasive and noninvasive regions. Invasion of normal brain is a cardinal feature of glioblastomas (GBM) and a major cause of treatment failure. DTI can identify invasive regions.
  
  
  METHODS
  In all, 50 GBM patients were imaged preoperatively at 3T with anatomic sequences, DTI, dynamic susceptibility perfusion MR (DSCI), and multivoxel spectroscopy. The DTI and DSCI data were coregistered to the spectroscopy data and regions of interest (ROIs) were made in the invasive (determined by DTI), noninvasive regions, and normal brain. Values of relative cerebral blood volume (rCBV), N-acetyl aspartate (NAA), myoinositol (mI), total choline (Cho), and glutamate + glutamine (Glx) normalized to creatine (Cr) and Cho/NAA were measured at each ROI.
  
  
  RESULTS
  Invasive regions showed significant increases in rCBV, suggesting angiogenesis (invasive rCBV 1.64 [95% confidence interval, CI: 1.5-1.76] vs. noninvasive 1.14 [1.09-1.18]; P < 0.001), Cho/Cr (invasive 0.42 [0.38-0.46] vs. noninvasive 0.35 [0.31-0.38]; P = 0.02) and Cho/NAA (invasive 0.54 [0.41-0.68] vs. noninvasive 0.37 [0.29-0.45]; P = < 0.03), suggesting proliferation, and Glx/Cr (invasive 1.54 [1.27-1.82] vs. noninvasive 1.3 [1.13-1.47]; P = 0.028), suggesting glutamate release; and a significantly reduced NAA/Cr (invasive 0.95 [0.85-1.05] vs. noninvasive 1.19 [1.06-1.31]; P = 0.008). The mI/Cr was not different between the three ROIs (invasive 1.2 [0.99-1.41] vs. noninvasive 1.3 [1.14-1.46]; P = 0.68). In the noninvasive regions, the values were not different from normal brain.
  
  
  CONCLUSIONS
  Combining DTI to identify the invasive region with perfusion and spectroscopy, we can identify changes in invasive regions not seen in noninvasive regions.
authors.affiliation: Neurosurgery Division, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.|Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Price
authors.affiliation: Neurosurgery Division, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Adam M H
authors.initials: AM
authors.lastname: Young
authors.affiliation: Neurosurgery Division, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: William J
authors.initials: WJ
authors.lastname: Scotton
authors.affiliation: Neurosurgery Division, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Jared
authors.initials: J
authors.lastname: Ching
authors.affiliation: University Department of Radiology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Laila A
authors.initials: LA
authors.lastname: Mohsen
authors.affiliation: Neurosurgery Division, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.|Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Natalie R
authors.initials: NR
authors.lastname: Boonzaier
authors.affiliation: Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Victoria C
authors.initials: VC
authors.lastname: Lupson
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, UK.
authors.forename: John R
authors.initials: JR
authors.lastname: Griffiths
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, UK.
authors.forename: Mary A
authors.initials: MA
authors.lastname: McLean
authors.affiliation: Neurosurgery Division, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.|Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Larkin
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000098:blood supply / Q000378:metabolism; D001932:Brain Neoplasms / Q000098:blood supply* / Q000378:metabolism*; D002560:Cerebrovascular Circulation; D003287:Contrast Media; D056324:Diffusion Tensor Imaging; D005260:Female; D005909:Glioblastoma / Q000098:blood supply* / Q000378:metabolism*; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D011446:Prospective Studies; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media
keywords: MR spectroscopy; diffusion tensor imaging; glioblastomas; invasive margin; perfusion MRI