Ultrasonic Phantoms

A realistic medium for studying imaging as well as dosimetric characteristics of medical ultrasound equipment should have ultrasonic properties simulating those of body tissues. Materials which have been incorporated in various attempts at producing tissue models include water, silastic and urethane materials, viscous oils and gels. We present data on the ultrasonic properties of water-based gel materials, which can be produced such that any tissue of the body is mimicked quantitatively with respect to density, speed of sound, attenuation coefficient and qualitatively with respect to backscatter; very importantly, the attenuation coefficient is nearly proportional to frequency as in the case of most soft tissues. The dependence of these properties on temperature is also reported. These materials have been used to construct phantoms for use in quality control of medical imaging equipment. In addition, realistic, yet geometrically simple anthropomorphic phantoms have been constructed for use in training programs and in assessing the performance of state-of-the-art scanning equipment.