Influence of tissue preparation on the acoustic properties of tissue sections at high frequencies.

The purpose of the present study was to clarify the influence of tissue preparation on the high-frequency acoustic properties by comparing the acoustic properties of the formalin-fixed, paraffin-embedded, deparaffinized sections and formalin-fixed, frozen sections for two types of fat-containing renal cancer and fat-free renal oncocytoma using a SAM. There was no significant difference for the sound speed among the clear cell, granular cell renal cancer and oncocytoma in either groups, but the attenuation constant was significantly higher for the frozen than for that of the paraffin section in fat-containing renal cancer. In fat-free oncocytoma, there was no significant difference for the attenuation constant in either group. The data suggest that the fat component, which had been eluted by paraffinization, is stored and the true acoustic properties of the tissue can be measured in frozen section.