3-D Microvessel-Mimicking Ultrasound Phantoms Produced With a Scanning Motion System

Abstract

Ultrasound techniques are currently being developed which can assess the vascularization of tissue as a marker for therapeutic response. Some of these ultrasound imaging techniques seek to extract quantitative features about vessel networks, while high-frequency imaging also allows individual vessels to be resolved. The development of these new techniques, and subsequent imaging analysis strategies, necessitates an understanding of their sensitivities to vessel and vessel network structural abnormalities. Constructing in-vitro flow phantoms for this purpose can be prohibitively challenging, as simulating precise flow environments with non-trivial structures is often impossible using conventional methods of construction for flow phantoms. Presented in this manuscript is a method to create predefined structures with < 10 μm precision using a three-axis motion system. The application of this technique is demonstrated for the creation of individual vessel and vessel networks, which can easily be made to simulate the development of structural abnormalities typical of diseased vasculature in-vivo. Additionally, beyond facilitating the creation of phantoms which would be otherwise very challenging to construct, the method presented herein enables one to precisely simulate very slow blood flow, respiration artifacts, and to measure imaging resolution.