PHANTOM MATERIALS FOR ELASTOGRAPHY

Acoustic and mechanical properties are reported for gelatin materials used to construct tissue-like phantoms for elasticity imaging (elastog raphy). A device and procedure for measuring elastic properties are de scribed. The measured compression forces were comparable to results ob tained from finite element analysis when linear elastic media are assu med. Also measured were the stress relaxation, temporal stability, and melting point of the materials. Aldehyde concentration was used to in crease the stiffness of the gelatin by controlling the amount of colla gen cross-linking. A broad range of tissue-like elastic properties was achieved with these materials, although gels continued to stiffen for several weeks. The precision for elastic modulus measurements ranged from less than 0.1% for 100 kPa samples to 8.9% for soft (< 10 kPa), s ticky samples.