Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30761
Quadratic Pulse Inversion Ultrasonic Imaging(QPI): A Two-Step Procedure for Optimization of Contrast Sensitivity and Specificity

Authors: Mamoun F. Al-Mistarihi


We have previously introduced an ultrasonic imaging approach that combines harmonic-sensitive pulse sequences with a post-beamforming quadratic kernel derived from a second-order Volterra filter (SOVF). This approach is designed to produce images with high sensitivity to nonlinear oscillations from microbubble ultrasound contrast agents (UCA) while maintaining high levels of noise rejection. In this paper, a two-step algorithm for computing the coefficients of the quadratic kernel leading to reduction of tissue component introduced by motion, maximizing the noise rejection and increases the specificity while optimizing the sensitivity to the UCA is presented. In the first step, quadratic kernels from individual singular modes of the PI data matrix are compared in terms of their ability of maximize the contrast to tissue ratio (CTR). In the second step, quadratic kernels resulting in the highest CTR values are convolved. The imaging results indicate that a signal processing approach to this clinical challenge is feasible.

Keywords: Ultrasonic Imaging, contrast agent, Volterra filter, Pulse Inversion

Digital Object Identifier (DOI):

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1262


[1] K. I. Kim and E. J. Powers, " A digital method of modeling quadratically nonlinear systems with a general random input," IEEE Trans. Acoust., Speech, Signal Processing, vol. 36, no. 11, pp. 1758- 1769, Nov. 1988.
[2] T. Koh and E. J. Powers, " Second-order volterra filtering and its application to nonlinear system identification," IEEE Trans. Acoust., Speech, Signal Processing, vol. ASSP-33, no. 6, pp. 1445-1455, Dec. 1985.
[3] J. Ophir and K. J. Parker, " Contrast agent in diagnostic ultrasound," Ultrasound in Med. & Biol., vol. 15, no. 4, pp. 319-333, Nov. 1989.
[4] D. H. Simpson, C. T. Chin, and P. N. Burns, " Pulse inversion Doppler: A new method for detecting nonlinear echoes from microbubble contrast agent," IEEE Trans. Ultrason., Ferroelect., Freq. Contr., vol. 46, no. 2, pp. 372-382, March 1999.
[5] H. Yao, P. Phukpattaranont, and E. S. Ebbini, " Post-beamforming second-order Volterra filter for nonlinear pulse-echo imaging," in Proc. ICASSP 2002, 2002, pp. 1133-1136.
[6] P. Phukpattaranont and E. S. Ebbini, "Post-beamforming second-order Volterra filter for nonlinear pulse-echo ultrasonic imaging," IEEE Trans. Ultrason., Ferroelect., Freg. Contr., vol. 50, no. 8, pp. 987-1001, Aug. 2003.
[7] P. Phukpattaranont, M. F. Al-Mistarihi and E. S. Ebbini, ÔÇÿPostbeamforming Volterra filters for contrast-assisted ultrasonic imaging: Invivo results," in Proc. IEEE Ultrason. Symp, 2003.
[8] M. F. Al-Mistarihi, E. S. Ebbini, "Quadratic Pulse Inversion Ultrasonic Imaging (QPI): Detection of Low-Level Harmonic Activity of Microbubble Contrast Agents," in Proc. ICASSP 2005, March 2005, vol. 2, pp. 1009-1012.