Method of making a solid tissue mimicking material for ultrasound

Abstract

A tissue mimicking material for use in ultrasound scanner phantoms has a very low acoustic backscatter coefficient. The tissue mimicking material has the ultrasonic speed and attenuation characteristics of human tissue, with a backscatter coefficient of about 40 dB below that of human liver tissue. The tissue mimicking material may be in liquid or solid form. A component in both the liquid and solid forms is a filtered aqueous mixture of large organic water soluble molecules and emulsion of fatty acid esters. This mixture may be based on a combination of evaporated whole milk and water. The material also includes a hydroxy compound, such as n-propanol, to control the ultrasonic speed of propagation through the material. A preservative from bacterial invasion, such as thimerosal, is also preferably included in the material. The solid form of the material contains the same material as the liquid form, with a very pure gel-forming material included to form a solid material. The tissue mimicking material may be included in an ultrasound phantom container with solid scattering particles and/or test objects incorporated therein. The use of scattering particles allows a very broad range of relative backscatter levels to be achieved in ultrasound test object phantoms incorporating the tissue mimicking material of the invention.