title: Quantitative assessment of blood volume and permeability in cerebral mass lesions using dynamic contrast-enhanced computed tomography in the dog.
abstract: OBJECTIVE
  To evaluate cerebral blood volume (CBV) and permeability (PS) in spontaneously occurring cerebral neoplastic and non-neoplastic lesions in dogs using dynamic contrast-enhanced computed tomography (DCE-CT).
  
  
  METHODS
  Dogs presenting with spontaneous intracranial lesions (n = 16) underwent DCE-CT at the level of the lesion followed by a histologically confirmed diagnosis from a CT-guided stereotactic biopsy. Data post-processing was performed with commercially available CT software (GEMS Advantage Workstation 4.2). Symmetric regions of interest (ROIs) were drawn within the lesion and unaffected areas on the contralateral side. Values were compared between lesion types and ratios of lesion-to-normal brain were calculated.
  
  
  RESULTS
  Dogs with extra-axial lesions (n = 3 meningiomas) had marked elevation of CBV and PS compared to normal brain. All Grade III gliomas (n = 5) had mildly elevated CBV and markedly elevated PS values. All lower Grade II gliomas (n = 2) had minimal elevation in CBV and PS. Dogs with non-neoplastic intra-axial lesions (one each necrotizing, fungal, and lymphoplasmacytic encephalitis) had elevation of PS with normal to mildly elevated CBV. Lesion-to-normal brain ratios for PS separated extra- and intra-axial neoplasms and intra-axial inflammatory/degenerative lesions from each other.
  
  
  CONCLUSIONS
  Low-grade gliomas do not consistently demonstrate elevated vascular parameters, whereas Grade III gliomas and non-neoplastic intra-axial lesions have elevated PS. Ratios between such lesions and normal brain may prove useful for differentiating types of lesions. These findings resemble those previously reported in similar lesions in people indicating that the dog may act as a good model for intracranial masses for the study of lesion angiogenesis and response to therapy.
authors.affiliation: Veterinary Medical Teaching Hospital, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: MacLeod
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Dickinson
authors.forename: Richard A
authors.initials: RA
authors.lastname: LeCouteur
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Higgins
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Pollard
mesh_terms: D000818:Animals; D001810:Blood Volume; D001811:Blood Volume Determination / Q000379:methods*; D001932:Brain Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D003287:Contrast Media; D004285:Dogs; D005910:Glioma / Q000098:blood supply / Q000000981:diagnostic imaging*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007479:Iopamidol; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D007479:Iopamidol