In vivo study of microcirculation in canine myocardium using the IVIM method†

Abstract
The intravoxel incoherent motion (IVIM) method was implemented in closed‐chest dogs to obtain measurements on microcirculation in the left ventricular wall in vivo. Specifically, it enabled us to measure the mean microflow velocity (400 ± 40 μm/s) and the vascular volume fraction (VVF) (11.1% ± 2.2%), and observe the directional preference of capillary orientation. The apparent diffusion coefficients (ADCs) of water along and perpendicular to myofibers were also measured. With vasodilatation by adenosine infusion, a 25% increase in the VVF and a 7% increase in the mean microflow velocity were observed, while no change in the ADC was detected. A 28.5% decrease of the ADC was observed postmortem. Magn Reson Med 50:531–540, 2003. Published 2003 Wiley‐Liss, Inc.