Assessment of wall velocity gradient imaging using a test phantom.

A new phantom has been designed to gain a better understanding of tissue Doppler imaging (TDI). Specifically, the phantom can easily be used to determine myocardial velocity gradients. The phantom mimics the left ventricle and is made of fine-grade sponge material whose ultrasound image closely resembles the gray scale image obtained from heart walls. Theoretical analysis of phantom wall movements offers a plausible explanation for the velocity gradients developing across the heart walls. The results of computer analysis were found to be in very good agreement with TDI M-mode recordings of phantom wall displacement.