Detailed motion analysis of the left ventricular myocardium using an MR tagging method with a dense grid

• Published in: Magnetic resonance in medicine Vol. 44; no. 1; pp. 73 - 82
• Main Authors: Urayama, Shin-ichi, Matsuda, Tetsuya, Sugimoto, Naozo, Mizuta, Shinobu, Yamada, Naoaki, Uyama, Chikao
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 01.07.2000; Williams & Wilkins
• Subjects: Algorithms; Biological and medical sciences; Cardiovascular system; Computer Simulation; dense-grid-tag; Humans; Image Processing, Computer-Assisted; Investigative techniques, diagnostic techniques (general aspects); left-ventricular-myocardium; Magnetic Resonance Imaging - methods; Medical sciences; MR-tagging; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Ventricular Function, Left - physiology; wall-motion-analysis; Human; Deformation measurement; Image analysis; Computer simulation; Motion study; Tagging; Medical imagery; Circulatory system; Diagnosis; Left ventricle performance; Nuclear magnetic resonance imaging
• ISSN: 0740-3194; 1522-2594
• DOI: 10.1002/1522-2594(200007)44:1<73::AID-MRM12>3.0.CO;2-X

Detailed analysis of myocardial deformation through a whole cardiac cycle was accomplished using a tagging method with a high‐density grid. Four sets of tagged images with a 4‐mm‐spacing grid were measured by generating four tagging pulses arranged at regular intervals in the cardiac cycle. Through each set of images, tag intersections were tracked semi‐automatically. The estimated motions of tag intersections were concatenated so that sequential positions of myocardium were connected through a whole cardiac cycle. In vitro evaluation of the precision of this technique showed that the mean error of tracked 4‐mm tag intersections was less than 0.47 ± 0.17 mm, even on the quite low‐contrast images, and the concatenation error caused by double concatenation was comparable to the interpolation error in the subendocardial area obtained with 8‐mm tag intersection motion. The small difference between the two mean distance curves of the in vivo evaluation indicated that the method is useful for analyzing heart wall abnormalities. Magn Reson Med 44:73–82, 2000. © 2000 Wiley‐Liss, Inc.