The importance of cells and arrangement of cells to ultrasound backscatter

The early work of Professor Floyd Dunn identified the importance of collagen structures and globular protein to ultrasound backscatter [Fields and Dunn, J. Acoust. Soc. Am. 54, 809–812 (1973)]. Recent advances in tissue characterization through ultrasound backscatter have again focused on determination of the underlying microstructures responsible for scattering. The focus of new models for ultrasound backscattering has been on the contribution of cells. Specifically, new models have sought to address the ultrasound backscatter from single cells and from different arrangement of cells. The importance of cells and their arrangements in tissues to classification of disease, i.e., cancer, through ultrasound was also noted by Professor Dunn [Saijo et al., Ultrasound Med. Biol. 17, 709–714 (1991)]. In the present work, the construction of a new cell model of scattering was made from measurements of acoustic properties of cells. Different arrangements of cells, i.e., uniform distribution of cells and cells arranged in groups, were examined in simulation using the new cell model. Finally, the new cell model and simulations were compared to ultrasound backscatter measurements from different kinds of cancer. The arrangement of cells within a cancerous region was observed to be significant for diagnostically differentiating between cancers using ultrasound backscatter.