Flow measurement by cardiovascular magnetic resonance: a multi-centre multi-vendor study of background phase offset errors that can compromise the accuracy of derived regurgitant or shunt flow measurements

Journal of Cardiovascular Magnetic Resonance

Research

Yingmin Liu¹  Philip J Kilner²  David N Firmin²  Peter D Gatehouse²  Juerg Schwitter³  Albert van Rossum⁴  Marijn P Rolf⁵  Mark BM Hofman⁵  John Totman⁶  Beat Werner⁷  Jeanette Schulz-Menger⁸  Matthias Dieringer⁸  Jochen von Spiczak⁹  Massimo Lombardi^1,10  Rebecca A Quest^1,11  Martin J Graves^1,12 

[1] Auckland MRI Research Group, University of Auckland, Auckland, New Zealand;CMR Unit, Royal Brompton Hospital, London, UK;Cardiac MRI Center, University Hospital Zurich, Zurich, Switzerland;Department of Cardiology, VU University Medical Center, Amsterdam, the Netherlands;Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, the Netherlands;Division of Imaging Sciences, King's College, London, UK;Division of Neuroradiology and Magnetic Resonance, University Children's Hospital, Zurich, Switzerland;Franz-Volhard-Klinik, Charité Universitätsmedizin, Berlin, Germany;Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland;Magnetic Resonance Laboratory, Italian National Research Council (CNR), Pisa, Italy;Radiological Sciences Unit, The Hammersmith Hospitals NHS Trust, London, UK;University Department of Radiology, Addenbrooke's Hospital, Cambridge, UK;

关键词: Cardiovascular Magnetic Resonance;    Scanner Type;    Regurgitant Fraction;    Velocity Encode;    Temporal Interpolation;   

DOI  :  10.1186/1532-429X-12-5

 received in 2009-10-08, accepted in 2010-01-14,  发布年份 2010

来源: Springer

【 摘 要 】

AimsCardiovascular magnetic resonance (CMR) allows non-invasive phase contrast measurements of flow through planes transecting large vessels. However, some clinically valuable applications are highly sensitive to errors caused by small offsets of measured velocities if these are not adequately corrected, for example by the use of static tissue or static phantom correction of the offset error. We studied the severity of uncorrected velocity offset errors across sites and CMR systems.Methods and ResultsIn a multi-centre, multi-vendor study, breath-hold through-plane retrospectively ECG-gated phase contrast acquisitions, as are used clinically for aortic and pulmonary flow measurement, were applied to static gelatin phantoms in twelve 1.5 T CMR systems, using a velocity encoding range of 150 cm/s. No post-processing corrections of offsets were implemented. The greatest uncorrected velocity offset, taken as an average over a 'great vessel' region (30 mm diameter) located up to 70 mm in-plane distance from the magnet isocenter, ranged from 0.4 cm/s to 4.9 cm/s. It averaged 2.7 cm/s over all the planes and systems. By theoretical calculation, a velocity offset error of 0.6 cm/s (representing just 0.4% of a 150 cm/s velocity encoding range) is barely acceptable, potentially causing about 5% miscalculation of cardiac output and up to 10% error in shunt measurement.ConclusionIn the absence of hardware or software upgrades able to reduce phase offset errors, all the systems tested appeared to require post-acquisition correction to achieve consistently reliable breath-hold measurements of flow. The effectiveness of offset correction software will still need testing with respect to clinical flow acquisitions.

【 授权许可】

Unknown   
© Gatehouse et al; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.