In vitro and in vivo evaluations of increased effective beam width for heat deposition using a split focus high intensity ultrasound (HIFU) transducer

. Author manuscript; available in PMC: 2009 Nov 1.

Published in final edited form as: Int J Hyperthermia. 2008 Nov;24(7):537–549. doi: 10.1080/02656730802064621

	Liver	Phantom
Density (kgm⁻³)	1065	1044
Speed of sound (m s⁻¹)	1549	1544
Attenuation (Np cm⁻¹MHz⁻¹)	0.049	0.009 – 0.021^**
Specific heat (J kg⁻¹K⁻¹)	3600	4270^*

Lafon et al. [24] more recently found this value of specific heat [39] to be more accurate than 5100, as originally presented.

^**

The attenuation slope for the phantom is given as 0.009 to 0.021Npcm⁻¹MHz⁻¹ for a range of BSA concentrations from 3 to 9%. Assuming a linear relationship exists between both factors, the following equation can be used for determining the attenuation at a set BSA concentration: