title: Usefulness of diffusion/perfusion-weighted MRI in rat gliomas: correlation with histopathology.
abstract: OBJECTIVE
  Diffusion/perfusion-weighted MRI (DWI/PWI) can provide additional useful information in the diagnosis of patients with brain gliomas in a noninvasive fashion. However, the exact role of these new techniques is still undergoing evaluation. Our hypothesis was that DWI and PWI could be useful for assessment of growth and vascularity of implanted C6 rat gliomas.
  
  
  METHODS
  Thirty-six rats were implanted with C6 glioma cells intracerebrally. Between 1 and 4 weeks after implantation, 8-10 rats were imaged on a clinical, 1.5-T whole-body magnetic resonance system with T(1)-weighted imaging (T(1)WI), T(2)-weighted imaging, DWI, PWI, and postcontrast T(1)WI at each weekly time point. All tumors were examined histologically; tumor cellularity and microvascular density were counted.
  
  
  RESULTS
  On DWIs, statistical differences of apparent diffusion coefficient values for both the tumoral core and peritumoral region were present comparing tumors of 3-4 weeks' growth with tumors of 1-2 weeks' growth. Apparent diffusion coefficient value of tumoral core was negatively correlated with tumor cellularity (r = -0.682, P < .01). Statistical difference of maximal regional cerebral blood volume of tumoral core was present comparing 2-4 weeks with both 1 week after implantation and contralateral white matter (P < .01). Native vessel dilation in regions of normal brain at the periphery of the tumors at 1 week after implantation was observed. Correlation between maximal regional cerebral blood volume of tumor core and microvascular density was present (r = 0.716, P < .01).
  
  
  CONCLUSIONS
  DWI and PWI has potential to characterize C6 gliomas in rats, which is a promising model similar to human gliomas.
authors.affiliation: Department of Radiology, Second Hospital of China Medical University, Shenyang, China. fanguog@vip.sina.com
authors.forename: Guoguang
authors.initials: G
authors.lastname: Fan
authors.forename: Peizhuo
authors.initials: P
authors.lastname: Zang
authors.forename: Fengdong
authors.initials: F
authors.lastname: Jing
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Wu
authors.forename: Qiyong
authors.initials: Q
authors.lastname: Guo
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology*; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005910:Glioma / Q000473:pathology*; D007124:Immunoenzyme Techniques; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003287:Contrast Media