Flow Velocity Mapping Using Contrast Enhanced High-Frame-Rate Plane Wave Ultrasound and Image Tracking: Methods and Initial in Vitro and in Vivo Evaluation.
Ultrasound imaging is the most widely used method for visualising and quantifying blood flow in medical practice, but existing techniques have various limitations in terms of imaging sensitivity, field of view, flow angle dependence, and imaging depth. In this study, we developed an ultrasound imaging velocimetry approach capable of visualising and quantifying dynamic flow, by combining high-frame-rate plane wave ultrasound imaging, microbubble contrast agents, pulse inversion contrast imaging and speckle image tracking algorithms. The system was initially evaluated in vitro on both straight and carotid-mimicking vessels with steady and pulsatile flows and in vivo in the rabbit aorta. Colour and spectral Doppler measurements were also made. Initial flow mapping results were compared with theoretical prediction and reference Doppler measurements and indicate the potential of the new system as a highly sensitive, accurate, angle-independent and full field-of-view velocity mapping tool capable of tracking and quantifying fast and dynamic flows.
Department of Bioengineering, Imperial College London, London, United Kingdom.
Chee Hau
CH
Leow
Department of Bioengineering, Imperial College London, London, United Kingdom.
Eleni
E
Bazigou
Department of Biomedical Engineering, King's College London, London, United Kingdom.
Robert J
RJ
Eckersley
Medical Engineering Program, University of Hong Kong, Pokfulam, Hong Kong.
Alfred C H
AC
Yu
Department of Bioengineering, Imperial College London, London, United Kingdom.
Peter D
PD
Weinberg
Department of Bioengineering, Imperial College London, London, United Kingdom. Electronic address: mengxing.tang@imperial.ac.uk.
Meng-Xing
MX
Tang
D000465:Algorithms; D000818:Animals; D001011:Aorta / Q000000981:diagnostic imaging* / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology; D003287:Contrast Media; D015150:Echocardiography, Doppler / Q000379:methods*; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D045423:Microbubbles; D019047:Phantoms, Imaging; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media
Atherosclerosis; Echo-particle image velocimetry; Flow; Image tracking; Microbubble contrast agents; Ultrafast ultrasound imaging; Ultrasound imaging velocimetry