Phantom experiments for measuring elasticity of breast cancer by the echo technique
© BioMed Central 2004
Published: 14 July 2004
Breast cancer is more stiff compared with benign lesions. The aim of the experiment is to measure the elasticity by pressing the breast with a water bag and measuring the shape change by the echo technique. The ultrasound frequency was 8 MHz. Two kinds of phantoms were created. One is made of silicone rubber 50 mm in thickness and inside is a polymethyl-methacrylate (PMMA) cylinder of diameter 20 mm. The PMMA cylinder is mocking the cancer and is placed with the surface at 10 mm and 20 mm depths from each silicone rubber surface. Another phantom is made of gelatine of 30 weight percent to water instead of silicone rubber. The phantoms were placed between two PMMA plates and pressed by a balloon filled with water, which is connected to a vessel by a rubber tube. The height of the vessel can be adjusted to change the pressure of the balloon. The silicone rubber phantom was too hard to be deformed by water pressure. The gelatine phantom was deformed around the PMMA cylinder by water pressure of up to 3.4 kPa. The gelatine surface was deformed by gravity without water pressure. Apparent differences of gelatine surface deformation depending on different water pressure were confirmed from the echogram thus obtained.