Ultrasonic attenuation and backscattering by mammalian organs as a function of time after excision.

Ultrasonic attenuation and backscattering were measured for bovine brain, spleen and liver and for porcine iiver as a function of time after excision for times up to 12Ohr. Tine attenuation coeificient exhibits insigniticant chaoges while the mean backscattering amplitude decreases substantiahy during the period such specimens are likely to be used. The changes in the two parameters are believed to reflect. in large measure, their origins, viz., the molecular level for attenuation and macrostructural level for backscattering.