A versatile flow phantom for intravoxel incoherent motion MRI

Magn Reson Med. 2012 Jun;67(6):1710-20. doi: 10.1002/mrm.23193. Epub 2011 Nov 23.


Although there have been many advancements in cancer research, much is still unknown about the heterogeneous tumor microenvironment. Diffusion-weighted MRI has proven to be a viable and versatile microstructural probe. Diffusion-weighted sequences specifically sensitive to intravoxel incoherent motion (IVIM) have seen a recent resurgence of interest as they promise to provide a valuable window on the vascular microenvironment. To understand, test, and optimize IVIM-sensitive approaches, a complex flow phantom was constructed to mimic certain characteristics of the tumor microenvironment such as tortuous microvasculature, heterogeneous vascular permeability, and interstitial fluid pressure buildup. Results using this phantom on a clinical scanner platform confirmed IVIM sensitivity to microscopic flow effects. Biexponential fitting of signal decay curves enabled quantitative extraction of perfusion fraction, IVIM-related pseudodiffusivity, and tissue diffusivity. Parametric maps were also generated, illustrating the potential utility of IVIM-sensitive imaging in clinical settings. The flow phantom proved to be an effective test-bed for validating and optimizing the IVIM-MRI technique to provide surrogate markers for microvascular properties.

MeSH terms

  • Equipment Design
  • Equipment Failure Analysis
  • Magnetic Resonance Angiography / instrumentation*
  • Motion
  • Reproducibility of Results
  • Rheology / instrumentation*
  • Sensitivity and Specificity