INTRODUCTION
The Doppler Flow phantoms provide a reliable means of evaluating a Doppler Flow Imaging
System's ability to detect the location and direction of flow, flow velocity and sensitivity.
The phantoms are constructed of a rubber-based tissue mimicking material. This material extends
the useful life of the phantom by avoiding problems due to melting, freezing, dehydration and
breakage from dropping, which are commonly associated with hydrogel (water-based) phantoms.
By eliminating these problems, the durability, quality and reliability of this product is guaranteed for
three years.
The acoustic properties of all biologic and non-biologic materials are affected by temperature
variations. Most diagnostic imaging systems and tissue-mimicking phantoms are calibrated at
room temperature, commonly referred to as 23°C. To ensure measurement accuracy ATS
incorporates a thermometer strip affixed to the outside surface of the phantom.
The sound velocity of most diagnostic imaging systems is calibrated to 1,540 meters per second
(mps), the assumed average velocity of sound through human soft tissue. The rubber-based
tissue-mimicking material has a sound velocity of 1450 mps with an attenuation coefficient of
0.5dB/cm/Mhz when measured using a 3.5 MHz transducer at room temperature (23°C).
The differences in the speed of sound if gone uncorrected, will cause distortion of the distance
(e.g. depth of penetration) measurements obtained. The measurements are corrected by
multiplying the measurements obtained by the correction factor of 0.94.
The rate of fluid flow through the phantom when measured by a Doppler imaging system is not
affected by the differences in sound velocity, therefore, distortion of these measurements will not
occur.
PRODUCT DESCRIPTION
The Model 527 tissue mimicking Doppler flow phantom is designed to test directional
discrimination of color Doppler flow imaging systems. This phantom monitors the ability of the
system to discriminate the direction of flow in small vessels, of close proximity, at varying depths.
The phantom contains four pairs of 2.0 mm flow channels. Connecting the channels (as shown in
Figure 2) creates bi-directional flow within the pair at equal flow rates. The edge-to-edge spacing
between the flow channels within the each pair progressively increases from 1.0 mm to 4.0 mm.
A fixed-angled scan surface maintains a constant angle between the sound beam and the test
fluid flowing through the phantom at 18° or 56° permitting continuous scanning at depths ranging
from 3.0 to 17.0 cm.
