title: The changes of brain water diffusion and blood flow on diffusion-weighted and perfusion-weighted imaging in a canine model of cardiac arrest.
abstract: OBJECTIVE
  To study the changes of brain water diffusion and cerebral haemodynamics of cortical areas using magnetic resonance imaging (MRI) in canine models of cardiac arrest (CA) and restoration of spontaneous circulation (ROSC). The secondary study objective was to evaluate whether MRI can be used to observe haemodynamic disorders in brain microcirculation.
  
  
  METHODS
  CA was induced in six beagle dogs using electrical stimulation followed by resuscitation to spontaneous circulation 3 min later. The dogs were scanned using MRI for echo planar, diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) with injection of Gd-diethylene triamine pentaacetic acid (DTPA) prior to induction of CA and 3 days after ROSC. The arterial blood pressure, unilateral common carotid artery flow and intracranial microcirculation were recorded.
  
  
  RESULTS
  All dogs successfully underwent electric-induced ventricular fibrillation which lasted 3 min and were resuscitated to maintain blood pressure stability. Serial MRI scans found that cerebral blood flow (RCBF) decreased in day 1 after ROSC and returned to baseline on day 3. Apparent diffusion coefficient (ADC), however, decreased on day 1 and remained lower than baseline on day 3, with 765.8±82.5×10(-6) mm(2) s(-1) on day 1 and 770.4±59.4×10(-6) mm(2) s(-1) on day 3 comparing to 855.8±43.4×10(-6) mm(2) s(-1) on baseline.
  
  
  CONCLUSIONS
  These data provide the evidence that early MRI can be used to observe acute haemodynamic disorders in brain microcirculation in a canine model of cardiac arrest.
authors: Department of Emergency, The First Affiliated Hospital, Sun Yat-sen University, 58, Zhongshan Road II, Guangzhou, Guangdong 510080, China.
authors: Rong
authors: R
authors: Liu
authors: Xin
authors: X
authors: Li
authors: Chun-lin
authors: CL
authors: Hu
authors: Li
authors: L
authors: Jiang
authors: Gang
authors: G
authors: Dai
authors: Gui-fu
authors: GF
authors: Wu
authors: Guo-qing
authors: GQ
authors: Huang
authors: Hong-yan
authors: HY
authors: Wei
authors: Xiao-xing
authors: XX
authors: Liao
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology* / Q000503:physiopathology; D004058:Diffusion; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D004285:Dogs; D017352:Echo-Planar Imaging; D005260:Female; D006323:Heart Arrest / Q000503:physiopathology*; D006439:Hemodynamics; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008833:Microcirculation; D023421:Models, Animal; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D012151:Resuscitation; D014693:Ventricular Fibrillation / Q000503:physiopathology*; D014867:Water
chemical_list: D014867:Water