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A Rotating Cylinder Phantom for Flow and Tissue Color Doppler Testing
Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
Centre for Clinical Research, Central Hospital, Västerås, Sweden.
Department of Clinical Physiology, Central Hospital, Västerås, Sweden.
Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
2009 (English)In: Ultrasound in Medicine and Biology, ISSN 0301-5629, Vol. 35, no 11, 1892-1898 p.Article in journal (Refereed) Published
Abstract [en]

Ultrasound Doppler using two-dimensional (2D) techniques is commonly used to study blood flow and myocardial tissue motion. This use includes measurement of velocity and time intervals, often in relation to the electrocardiogram (ECG) signal. 2D Doppler is frequently considered a real-time technique but in reality the acquisition time can be as long as 200 ms per image. We have developed a test-phantom using a rotating cylinder to simulate blood flow and tissue motion in a whole sector or space angle to evaluate velocity and timing characteristics.The phantom can produce constant velocities for velocity testing, as well as accelerating movement for testing the timing characteristics of ultrasound systems. Our investigation shows that the cylinder phantom is especially suitable for timing measurements in 2D Doppler imaging and that time delays between the Dopplersignals and the ECG signal exist in the tested ultrasound system.

Place, publisher, year, edition, pages
Elsevier , 2009. Vol. 35, no 11, 1892-1898 p.
Keyword [en]
Doppler phantom, Time delay, Color Doppler, Tissue Doppler, Echocardiography
National Category
Natural Sciences
URN: urn:nbn:se:liu:diva-51372DOI: 10.1016/j.ultrasmedbio.2009.06.1095ISI: 000278012000013OAI: diva2:274463
Available from: 2009-10-29 Created: 2009-10-29 Last updated: 2014-09-03Bibliographically approved
In thesis
1. Testing of Doppler Ultrasound Systems
Open this publication in new window or tab >>Testing of Doppler Ultrasound Systems
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Blood and tissue velocities are measured and analyzed in cardiac, vascular, and other applications of diagnostic ultrasound. Errors in system performance might give invalid measurements.

We developed two moving string test targets and a rotating cylinder phantom (Doppler phantoms) to characterize Doppler ultrasound systems. These phantoms were initially used to measure such variables as sample volume dimensions, location of the sample volume, and the performance of the spectral analysis. Later, specific tests were designed and performed to detect errors in signal processing, causing time delays and inaccurate velocity estimation in all Doppler modes.

In cardiac motion pattern even time delays as short as 30 ms may have clinical relevance. These delays can be obtained with echocardiography by using flow and tissue Doppler and M-mode techniques together with external signals (e.g., electrocardiography (ECG) and phonocardiography). If one or more of these signals are asynchronous in relation to the other signals, an incorrect definition of cardiac time intervals may occur. To determine if such time delays in signal processing are a serious problem, we tested four commercial ultrasound systems. We used the Doppler string phantom and the rotating cylinder phantom to obtain test signals. We found time delays of up to 90 ms in one system, whereas delays were mostly short in the other systems. Further, the time delays varied relative to system settings. In two-dimensional (2D) Doppler the delays were closely related to frame rate.

To determine the accuracy in velocity calibration, we tested the same four ultrasound systems using the Doppler phantoms to obtain test signals for flow (PW) and tissue (T-PW) pulse Doppler and for continuous wave (CW) Doppler. The ultrasound systems were tested with settings and transducers commonly used in cardiac applications. In two systems, the observed errors were mostly close to zero, whereas one system systematically overestimated velocity by an average of 4.6%. The detected errors are mostly negliable in clinical practice but might be significant in certain cases and research applications.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2009. 55 p.
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1284
National Category
Natural Sciences
urn:nbn:se:liu:diva-51213 (URN)978-91-7393-498-5 (ISBN)
Public defence
2009-11-20, Gamla Vårdskolans aula, ingång 21, Centrallasarettet, Västerås, Västerås, 13:15 (Swedish)
Available from: 2009-10-29 Created: 2009-10-21 Last updated: 2009-10-29Bibliographically approved

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