title: Time evolution of cerebral perfusion and apparent diffusion coefficient measured by magnetic resonance imaging in a porcine stroke model.
abstract: OBJECTIVE
  To demonstrate the feasibility of sequential diffusion-weighted (DW) and perfusion-weighted (PW) magnetic resonance imaging (MRI) of a recently developed porcine stroke model and to evaluate the evolution of cerebral perfusion and the apparent diffusion coefficient (ADC) over time. Materials and Methods In five pigs, DW imaging (DWI) and PW imaging (PWI) was carried out for 7 hours after stroke onset, starting 1 hour after middle cerebral artery occlusion (MCAO).
  
  
  RESULTS
  The DWI lesion volume increased significantly with time, and final DWI lesion volume correlated well with lesion area on histological sections (r = 0.910). T2 changes could be recognized 3 hours after stroke onset. At 1 hour the ADC ratio (ischemic lesion/contralateral side) was reduced to 0.81 in the caudate-putamen and to 0.87 in the cortex, and the cerebral blood flow ratio was reduced to 0.40 in the caudate-putamen and 0.51 in the cortex.
  
  
  CONCLUSIONS
  The level of flow reduction in the caudate-putamen and the cortex after 1 hour is in good correlation with human thresholds of irreversible and reversible ischemic damage, and accordingly, this model might be a model for mechanisms of infarct evolution and therapeutic intervention.
authors.affiliation: Department of Neuroradiology, Arhus University Hospital, Arhus, Denmark. Lisbeth@pet.auh.dk
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Røhl
authors.forename: Masaharuh
authors.initials: M
authors.lastname: Sakoh
authors.forename: Claus Ziegler
authors.initials: CZ
authors.lastname: Simonsen
authors.forename: Peter
authors.initials: P
authors.lastname: Vestergaard-Poulsen
authors.forename: Ryan
authors.initials: R
authors.lastname: Sangill
authors.forename: Jens Cristian
authors.initials: JC
authors.lastname: Sørensen
authors.forename: Carsten Reidies
authors.initials: CR
authors.lastname: Bjarkam
authors.forename: Carsten
authors.initials: C
authors.lastname: Gyldensted
authors.forename: Leif
authors.initials: L
authors.lastname: Østergaard
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002560:Cerebrovascular Circulation; D004058:Diffusion; D004195:Disease Models, Animal; D018450:Disease Progression; D005240:Feasibility Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D020521:Stroke / Q000473:pathology / Q000503:physiopathology*; D013552:Swine; D013997:Time Factors