title: In vivo diffusion-weighted imaging of liver tumor necrosis in the VX2 rabbit model at 1.5 Tesla.
abstract: OBJECTIVE
  We sought to demonstrate the feasibility of using single-shot spin-echo echo-planar imaging for imaging liver tumor necrosis in the in vivo VX2 rabbit model at 1.5 T.
  
  
  METHODS
  VX2 liver tumors were grown in 4 rabbits. Diffusion-weighted images (DWIs) were acquired during breath-hold using twice refocused SE-EPI (b = 0, 700, 1400 seconds/mm). Anatomic images for tumor size measurements were acquired using T2W TSE. Rabbits were euthanized for subsequent necropsy. Viable and necrotic tumor tissue ADC measurements were performed with reference to hematoxylin and eosin pathology.
  
  
  RESULTS
  A total of 8 tumors were grown with diameters ranging from 1.2 to 5.3 cm. Viable and necrotic tumor compartments were clearly differentiated. Apparent diffusion coefficient in necrotic tumor cores, 1.26 +/- 0.11 x 10 mm/s, were significantly greater than those in surrounding viable tumor tissues, 0.74 +/- 0.06 x 10 mm/s (mean +/- SD, P < 0.05).
  
  
  CONCLUSIONS
  In vivo DWI of liver tumor necrosis in the VX2 rabbit model is feasible using a 1.5 T clinical magnetic resonance imaging scanner. DWI may permit longitudinal assessment of liver tumor therapies in both preclinical and clinical studies.
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Il 60611, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Deng
authors.forename: Thomas K
authors.initials: TK
authors.lastname: Rhee
authors.forename: Kent T
authors.initials: KT
authors.lastname: Sato
authors.forename: Riad
authors.initials: R
authors.lastname: Salem
authors.forename: Kenneth
authors.initials: K
authors.lastname: Haines
authors.forename: Tatjana
authors.initials: T
authors.lastname: Paunesku
authors.forename: Mary F
authors.initials: MF
authors.lastname: Mulcahy
authors.forename: Frank H
authors.initials: FH
authors.lastname: Miller
authors.forename: Reed A
authors.initials: RA
authors.lastname: Omary
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Larson
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D005240:Feasibility Studies; D007091:Image Processing, Computer-Assisted; D008113:Liver Neoplasms / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009336:Necrosis; D011817:Rabbits