Direct Measurement of Myocardial Thickening by Means of Computer Vision
M. Sühling, M. Arigovindan, C.H.P. Jansen, A. Linka, P. Buser, C. Heidegger, S. Marsch, P. Hunziker, M. Unser
Menarini prize for echocardiography of the Working Group for Echocardiography of the Swiss Society of Cardiology, Actes de l'assemblée annuelle commune, Société Suisse de Cardiologie, Société Suisse de Chirurgie Thoracique et Cardio-Vasculaire, Société Suisse de Médecine Intensive, Lausanne VD, Swiss Confederation, May 8-10, 2003, vol. 6, supp. 5, pp. 16 S.
Menarini Prize for Echocardiography of the Working Group for Echocardiography of the Swiss Society of Cardiology.
Background: Systolic myocardial contraction combining radial thickening and circumferential/longitudinal shortening is probably the most important function of the heart, but this holy grail is difficult to measure echocardiographically, except by subjective visual assessment.
Methods and result: To overcome this problem, we designed a novel echocardiographic method that is based on computer vision technology. It works with conventional echo images, does not need tissue Doppler and is independent from the ultrasound beam angle. Fundamentally, the method regards the entire image information as a mathematical problem where a minimal-error solution is to be found by techniques of linear algebra. This technique measures myocardial radial thickening and circumferential shortening concomitantly with quantitative display of the results either as full vector information or in a simplified manner in color-coded fashion. Notably, passive heart motion and active contraction is inherently discriminated by demonstration of myocardial motion in the absence of thickening in the same location. This method also overcomes the fundamental weakness of Doppler-based strain rate imaging that fails to show wall thickening components that are not aligned to the beam. After design and implementation of the method, we validated the results in echo images synthesized to contain predefined motion and thickening (as there is no available in vivo gold standard) and found convincing results. When applied to clinical echocardiograms, first results show that thickening determined by this new method corresponds to visual judgement. Ongoing work focuses on larger application in experimental and clinical echocardiograms and on comparison with novel Doppler methods.
Conclusion: Echocardiography is now able to determine myocardial radial thickening and circumferential/longitudinal shortening quantitatively and objectively. Of particular interest for the study of ischemic heart disease is the ability to automatically separate translation of the heart from true thickening in the same myocardial segment. If the ongoing clinical validation studies confirm these findings, we expect that this fascinating new approach will have a significant impact on echocardiography and, in particular, on stress echo.
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AUTHOR="S{\"{u}}hling, M. and Arigovindan, M. and Jansen, C.H.P. and
Linka, A. and Buser, P. and Heidegger, C. and Marsch, S. and
Hunziker, P. and Unser, M.",
TITLE="Direct Measurement of Myocardial Thickening by Means of Computer
Vision",
BOOKTITLE="Actes de l'assembl{\'{e}}e annuelle commune,
Soci{\'{e}}t{\'{e}} Suisse de Cardiologie, Soci{\'{e}}t{\'{e}}
Suisse de Chirurgie Thoracique et Cardio-Vasculaire,
Soci{\'{e}}t{\'{e}} Suisse de M{\'{e}}decine Intensive",
YEAR="2003",
editor="",
volume="6, Supplementum 5",
series="",
pages="16 S",
address="Lausanne VD, Swiss Confederation",
month="May 8-10,",
organization="",
publisher="",
note="Menarini prize for echocardiography of the Working Group for
Echocardiography of the Swiss Society of Cardiology")