untitled.html

<h1 data-label="896397" class="ltx_title_section">Goals:</h1><div>                                        </div><div>Quantitative ultrasound (QUS) characterization based on  frequency analysis of the backscatter radio frequency (RF) data has seen  success in a number of applications. </div><div>    </div><div>Theoretical model has been developed to relate the gated  normalized power spectrum to the scattering properties of investigated tissue. Localized  changes in compressibility and density induces local changes in the gated RF. The  autocorrelation of the medium is approximated equal to the Fourier transform of  RF. Under Born approximation and plane wave sonification, closed form solution  for the scattering size and scattering concentration can be derived. </div><div>    </div><div>However, normalized spectrum analysis requires the use of  a reference phantom to remove the system dependent transfer function and  diffraction effects. This usage of the reference phantom hinders the adoption  of QUS into clinical practice. And this technique does not account for the  layers in front of the tissue. </div><div>    </div><div>Question: to what extent QUS do not need the reference  phantom? Which is to say the scattering and attenuation variations are dominating  the diffraction and acoustical-electro conversion variations. </div><div>    </div><div>Can we do QUS with a simpler and more practical reference  phantom for some specific applications? By embedded a sphere inside a body in a  semi-invasive procedure, we have more reliable calibration. </div><div>    </div><div>Layers effect: no work has been done to compensate for the  layer before the tissue in question. The layer effect compensation is important  for QUS to be accurate and applicable. </div><div>    </div><div>BSC are frequency dependent. It is critical to publish the  data publicly. </div><div>    </div><div>BSC measurement inter laboratory gave inconsistent results  for tissue mimicking phantom. Attenuation and diffraction compensation is  difficult. </div><div>            </div><h1 data-label="236876" class="ltx_title_section">Relationship between Gated Power Spectrum and Tissue Microstructure</h1>