Transverse Spectral Analysis in Stenosis Diagnosis Using Transversely Oscillating Acoustic Field

Accurate estimation of maximum velocities in Doppler blood flow spectrograms is vital in diagnosis of cardiovascular anomalies such as stenosis. However, obtaining accurate maximum velocity is not straightforward due to intrinsic spectral broadening and variance in the power spectrum estimate. Therefore, employment of Doppler indices such as pulsatility index is commonplace. Moreover, the results attained by conventional blood spectrogram estimators fail when beam to flow angle is near to 90°. In this work, an approach for estimation of pulsatility index for a fully transverse blood flow is presented. The method has been validated using simulated Doppler signal with scatterers possessing the pulsating flow of femoral artery in Womersley-Evan's model. By investigation of three scenarios of a normal vessel, and vessel with 20% and 40% stenosis, the possibility of stenosis diagnosis is discussed.