Development of complex tissue-mimicking phantoms for quantification of flow by the time-intensity method in contrast enhanced ultrasound imaging

Currently, there are few simple-to-construct in vitro, wall-less phantoms that have accurate acoustic properties while mimicking the complex normal and neoplastic geometries of the vascular network. The purpose of this study was to develop agar-based tissue-mimicking phantoms (TMP) to model such networks. Three types of vascular networks were considered: (1) single vessel, (2) multi-vessel with artery bifurcations, and (3) multi-vessel with artery bifurcations and structural abnormalities typical of diseased (tumor) vascular networks. Blood-flow related parameters were derived from the time-intensity curves obtained from the bolus injection of a lipid-based microbubble ultrasound contrast agent (UCA) under varying flow conditions relevant to our ongoing work in developing techniques to simultaneously quantify both the total volume and flow measurements within a tumor phantom. A Fukuda Denshi Ultrasound system was used with a linear probe (LG308-16A) positioned transversely and longitudinally to the direct...