Using High Frequency Ultrasound Envelope Statistics to Determine Scatterer Number Density in Dilute Cell Solutions

It has previously been demonstrated in tissue-mimicking phantoms and in tissue that envelope statistics of US backscatter are affected by changes in the scatterer properties [1–4, 32, 37]. At higher frequencies the wavelength of the US begins to approach the size of cells and cellular components and at this scale the envelope statistics of HFUS backscatter become more sensitive to structural changes within cells. To investigate the relation between the envelope statistics and cell structure, experiments were performed in vitro. The physical meaning of the fit parameters was evaluated by investigating HFUS backscatter from suspensions of various concentrations of two different cell lines of different sizes.