User Guide
18
ZERDINE
®
The Model 040GSE is constructed from a patented, solid elastic material devel-
oped at CIRS called Zerdine. Phantoms constructed from Zerdine will not melt or
leak when punctured and they do not require refrigeration. Zerdine is also more
elastic than other materials and allows more pressure to be applied to the scanning
surface without subsequent damage to the material. At normal room temperatures,
Zerdine will accurately simulate the ultrasound characteristics found in human liver
tissue. Specic proprietary fabrication procedures enable close control over the
homogeneity of Zerdine and the reliability of its acoustic characteristics from batch
to batch.
The formulation system established at CIRS is geared to independently control:
• The speed of sound in the optimal range of 1510 to 1700 m/s.
• Attenuation in the optimal range of 0.05 and 1.5 dB/cm-MHz.
• Scatter or relative contrast in the optimal range of -15 to +15 dB in
relation to a scatter baseline equivalent to human liver tissue.
• Elasticity with a Young Modulus in the optimal range of 4 to 100 kPa.
At normal room temperature, Zerdine response to ultrasonic excitations will simulate
the ultrasonic response of human tissue. The relation between the acoustic attenu-
ation, A, and the acoustic frequency, F, is of the form A = A
o
F
n
with values of the
power coefcient, n, in the range of 0.8 to 1.10, indicating the proportional increase
of the acoustic attenuation with frequency. Backscatter characteristics can be ad-
justed through the addition of predetermined amounts of calibrated scatter material,
and are fully compatible with harmonic imaging. Zerdine can be molded into very
intricate shapes, and the material can be cured in layers allowing the production of
“multi-tissue” phantoms. Zerdine, like most other phantom materials, will desiccate
if unprotected; thus, all phantoms must be stored properly. If stored in the case
provided, your phantom should last many years.