title: MR evaluation of vessel size imaging of human gliomas: Validation by histopathology.
abstract: OBJECTIVE
  To compare the vessel size and the cerebral blood volume in human gliomas with histopathology. Vessel size imaging (VSI) is a dynamic susceptibility contrast method for the assessment of the vessel size in normal and pathological tissue. Previous publications in rodents showed a satisfactory conformity with the vessel size derived from histopathology. To assess the clinical value, further, the progression-free interval was determined and correlated.
  
  
  METHODS
  Twenty-five gliomas (WHO grade °II [n = 10], °III [n = 3], °IV [n = 12]) were prospectively included and received a stereotaxic biopsy after VSI. The vessel size and the cerebral blood volume (CBV) were calculated in regions of interest at the tumor edge and correlated with the vessel size measured by histopathology.
  
  
  RESULTS
  Both VSI and CBV showed a good correlation with the vessel size in histopathology (up to r = 0.84, P < 0.001, and r = 0.62, P < 0.001, respectively). Slope and offset of the linear regression (y = 0.77x + 0.36 μm) suggest that the size of normal capillaries is overestimated with VSI, while for grossly enlarged vessels an underestimation occurs. Both VSI and CBV were negatively correlated with the progression-free interval (r = -0.57, P = 0.008, and r = -0.50, P = 0.025, respectively).
  
  
  CONCLUSIONS
  The correlation between VSI and vessel size from histopathology is in good accordance with the animal studies. The overestimation of small capillary sizes is also known from the animal trials. Vessel size and CBV showed similar results, both for the correlation with the histopathological vessel size and the progression-free interval.
authors: Department of Radiology, Medical Physics, University Medical Center Freiburg, Germany.
authors: Elias
authors: E
authors: Kellner
authors: Department of Neuroradiology, University Medical Center Freiburg, Germany.
authors: Tobias
authors: T
authors: Breyer
authors: Siemens AG, Healthcare Sector, Erlangen, Germany.
authors: Peter
authors: P
authors: Gall
authors: Department of Neuropathology, University Medical Center Freiburg, Germany.
authors: Klaus
authors: K
authors: Müller
authors: Department of Stereotactic Neurosurgery, University Medical Center Freiburg, Germany.
authors: Michael
authors: M
authors: Trippel
authors: Department of Neuropathology, University Medical Center Freiburg, Germany.
authors: Ori
authors: O
authors: Staszewski
authors: Department of Neuropathology, University Medical Center Freiburg, Germany.
authors: Florian
authors: F
authors: Stein
authors: Department of Neuroradiology, University Medical Center Freiburg, Germany.
authors: Olaf
authors: O
authors: Saborowski
authors: Department of Radiology, Medical Physics, University Medical Center Freiburg, Germany.
authors: Olga
authors: O
authors: Dyakova
authors: Department of Neuroradiology, University Medical Center Freiburg, Germany.
authors: Horst
authors: H
authors: Urbach
authors: Department of Radiology, Medical Physics, University Medical Center Freiburg, Germany.
authors: Valerij G
authors: VG
authors: Kiselev
authors: Department of Neuroradiology, University Medical Center Freiburg, Germany.
authors: Irina
authors: I
authors: Mader
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D001810:Blood Volume; D001811:Blood Volume Determination / Q000379:methods; D001932:Brain Neoplasms / Q000098:blood supply / Q000473:pathology*; D005910:Glioma / Q000098:blood supply / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000473:pathology* / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: cerebral blood volume; gliomas; perfusion weighted imaging; vessel size imaging