Category: Transient Plane Source
Keywords: biological tissues, bone, diagnostic ultrasound, fat, in vivo, muscle, SAM, scanning acoustic macroscope, scanning acoustic macroscope (SAM), speed of sound, Temperature, Thermal Conductivity, Thermal Diffusivity, ultrsonic attenuation, vivo porcine tissue
Abstract: The measurement of thermal and ultrasonic properties of biological tissues is essential for the assessment of the temperature rise induced in vivo by diagnostic ultrasound. In this paper, we present measurements of thermal conductivity, thermal diffusivity, speed of sound and ultrasonic attenuation of fresh ex vivo porcine tissue, namely 'muscle' (from abdomen and leg), 'skin with subcutaneous fat' (from abdomen and leg), 'abdominal fat' and 'bone'. The measurements of the thermal properties of biological tissue samples are based on a transient method.' They found that subcutaneous fat has the lowest thermal conductivity (0.23 W/mK) while muscle has the highest value of 0.46 W/mK. Thermal diffusivity of muscle tissue recorded the highest value among the studied tissues (0.16 mm2/s) while that of skin with subcutaneous fat gave the lowest value of 0.11 mm2/s. They used a SAM to measure attenuation coefficients and speed of sound for the tissue samples. They concluded that the results for the speed of sound are broadly similar to those reported in the literature.
Reference: Journal of Medical Engineering and Technology, 33, 3, (2009) 249-256