[Intravoxel incoherent motion (IVIM) imaging using an experimental MR unit with small bore]

IVIM images were constructed from a pair of spin echo (SE) sequences on a 2T MR unit with small bore. In the current study, two types of SE were used: the standard SE and the other sensitized to microscopic incoherent motion by adding motion probing gradient on either side of 180 degrees pulse. IVIM images of water and acetone phantoms were generated, and the diffusion coefficients obtained from these materials were consistent with the literature values. IVIM images of implanted human tumor in nude mouse showed relatively high apparent diffusion coefficient (2.0 x 10(-3) mm2/sec). However, in the sacrificed mouse, diffusion coefficient in the tumor was markedly decreased (0.5 x 10(-3) mm2/sec), which suggested the considerable contribution of perfusion to ADC. In conclusion, IVIM imaging was thought to be highly valuable because it can provide functional information about tumor perfusion.