Motion compensation for intravascular ultrasound palpography

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 53; no. 7; pp. 1269 - 1280
• Main Authors: Leung, K.Y. Esther, Baldewsing, Radjkumarsing A., Mastik, Frits, Schaar, Johannes Antonius, Gisolf, Andries, van der Steen, Antonius F.W.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.07.2006; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustics; Acute coronary syndromes; Algorithms; Arteries; Biological and medical sciences; Blocking; Cardiology; Cardiovascular system; Catheters; Coronary Vessels - diagnostic imaging; Echocardiography - methods; Estimates; Exact sciences and technology; Fundamental areas of phenomenology (including applications); General equipment and techniques; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Imaging; In vivo; Information Storage and Retrieval - methods; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Investigative techniques, diagnostic techniques (general aspects); Matching; Medical sciences; Methods; Miscellaneous. Technology; Motion compensation; Movement; Palpation; Physics; Radio frequencies; Radio frequency; Reproducibility of Results; Sensitivity and Specificity; Strain; Transducers; Ultrasonic investigative techniques; Ultrasonics, quantum acoustics, and physical effects of sound; Ultrasonography, Interventional - methods; Ultrasound; Human; Motion estimation; Coronary artery; Intravascular space; Rupture; Catheter; Phased array; Radiofrequency; Block matching; Intraluminal; Tissue; Cross correlation; Medical imagery; Acoustic antenna; Endoscopy; Cardiology; Acoustic image; Rotation measure; Alignment defect; Elastography; Transducer network; Stress measurement
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2006.1665075

Rupture of vulnerable plaques in coronary arteries is the major cause of acute coronary syndromes. Most vulnerable plaques consist of a thin fibrous cap covering an atheromous core. These plaques can be identified using intravascular ultrasound (IVUS) palpography, which measures radial strain by cross-correlating RF signals at different intraluminal pressures. Multiple strain images (i.e., partial palpograms) are averaged per heart cycle to produce a more robust compounded palpogram. However, catheter motion due to cardiac activity causes misalignment of the RF signals and thus of the partial palpograms, resulting in less valid strain estimates. To compensate for in-plane catheter rotation and translation, we devised four methods based on block matching. The global rotation block matching (GRBM) and contour mapping (CMAP) methods measure catheter rotation, and local block matching (LBM) and catheter rotation and translation (CRT) estimate displacements of local tissue regions. These methods were applied to nine in vivo pullback acquisitions, made with a 20 MHz phased-array transducer. We found that all these methods significantly increase the number of valid strain estimates in the partial and compounded palpograms (P < 0.008). The best method, LBM, attained an average increase of 17% and 15%, respectively. Implementation of this method should improve the information coming from IVUS palpography, leading to better vulnerable plaque detection.