Using high frequency ultrasound envelope statistics to determine scatterer number density in dilute cell solutions

Abstract

It has previously been demonstrated in tissuemimicking 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.

Ultrasonic backscatter coefficient quantitative estimates from high-concentration Chinese hamster ovary cell pellet biophantoms

“…There have also been efforts to understand scattering using approaches such as three-dimensional acoustic impedance map (3DZM) (Mamou et al, 2005;Dapore et al, 2011;Pawlicki et al, 2011), single cell scattering Falou et al, 2010), dilute cell solution (Tunis et al, 2005), isolated nuclei (Taggart et al, 2007), dense cell aggregate (Taggart et al, 2007), and numerical simulations (Doyle et al, 2009). Inspired by the physical phantoms, biophantoms likewise have been used as a technique to elucidate scattering phenomena.…”

The use of optical coherence tomography envelope statistics to quantify local temperature changes in tissue-mimicking phantoms

“…High frequency US is highly responsive to structural changes experienced by scatterers, which makes this highly applicable for monitoring therapeutic outcomes. Assessment protocols for cancer treatments have patients receive a full treatment regiment before examining the progress of the treatment results with respect to tumor size or cellular alterations [44]. Tunis et al, has used envelope statistics to quantify structural changes that transpire during apoptosis and necrosis, which has provided a viable solution to monitoring tumor response during treatment in a non-invasive procedure [44].…”

“…Assessment protocols for cancer treatments have patients receive a full treatment regiment before examining the progress of the treatment results with respect to tumor size or cellular alterations [44]. Tunis et al, has used envelope statistics to quantify structural changes that transpire during apoptosis and necrosis, which has provided a viable solution to monitoring tumor response during treatment in a non-invasive procedure [44]. The study analyzed the statistical parameters of the Generalized Gamma model where the number density of the two solutions overlaps, the scale parameter a is larger for PC-3 cells [44].…”

“…Tunis et al, has used envelope statistics to quantify structural changes that transpire during apoptosis and necrosis, which has provided a viable solution to monitoring tumor response during treatment in a non-invasive procedure [44]. The study analyzed the statistical parameters of the Generalized Gamma model where the number density of the two solutions overlaps, the scale parameter a is larger for PC-3 cells [44]. This is consistent with the theory that parameter a reflects the cross-section of the scatterer.…”

The measurement of ultrasound backscattering from cell pellet biophantoms and tumors ex vivo

“…For groupings of cells under various conditions, Tunis et al (2005a) applied envelope statistics of ultrasound backscatter to determine the scatterer number density in dilute cell solutions. However, a statistical model was used that assumed point scatterers and the study did not deal with anatomic structure of groupings of cells.…”