TRADITIONAL POSTER - ismrm

Poster Sessions
1360. Is 2-D Velocity Encoded Cardiac MRI Accurate at 3T?
Lindsay Marie Zeeb 1 , Jeffrey Kaye, Curtis E. Green 1 , Trevor J. Andrews, George Ernest Gentchos 1
1 Radiology, University of Vermont, Burlington, VT, United States
2-D Velocity encoded MRI (VEC-MRI) has not been widely validated at 3T field strength with regard to optimal imaging parameters and overall accuracy.
In this study, 2D VEC-MRI at 3T was tested in vivo over a wide range of imaging parameters and compared to well validated cine functional volumes.
VEC-MRI was highly accurate over a wide range of velocity encoded values, orientation of flow and at varying spatial resolution. This suggests that 2D
VEC-MRI is highly accurate at 3T field strength and that further efforts to increase signal to noise or spatial resolution are probably not necessary compared
to 1.5 T.
1361. 4D Blood Flow in the Left Heart
Daniela Foell 1 , Steffen Taeger 2 , Bernd Jung 3 , Jelena Bock 3 , Philipp Blanke 3 , Christoph Bode 2 , Michael
Markl 3
1 Cardiology , University Hospital , Freiburg, Germany; 2 Cardiology, University Hospital, Freiburg, Germany; 3 Diagnostic
Radiology/Medical Physics, University Hospital, Freiburg, Germany
Flow-sensitive 4D MRI was performed to visualize the complex blood flow in the left ventricle (LV), atrium and out-flow tract. Left atrial and LV vortex
formation was seen in older and younger volunteers. The left pulmonary veins promote more pronounced vortexes in older and younger volunteers during
systole and diastole. Intraventricular vortex formation was not different between older and younger individuals with most vortexes located in basal and
midventricular parts of the LV. The knowledge of blood flow in the healthy heart is essential for further patient studies in cardiac disease such as LV
aneurysms, valve insufficiencies or atrial arrhythmia.
1362. Acquisition of Velocity-Encoded CMR Is Feasible in Presence of Contrast Agent, But Delineation for
Strain Is Difficult
Erik Hedstrom 1 , Erik Bergvall 1 , Karin Markenroth Bloch 2,3 , Freddy Stahlberg 4,5 , Hakan Arheden 1
1 Cardiac MR Group, Department of Clinical Physiology, Lund University and Lund University Hospital, Lund, Sweden; 2 MR
department, Lund University Hospital, Lund, Sweden; 3 Philips Medical Systems, Best, Netherlands; 4 Department of Medical
Radiation Physics, Lund University, Lund, Sweden; 5 Department of Radiology, Lund University Hospital, Lund, Sweden
AIM: We sought to determine whether the presence of contrast agent affects PC-CMR measurements of aortic blood flow, and myocardial displacement of
the left ventricle in humans. METHODS: Velocity-encoded data was acquired pre and post contrast agent administration. RESULTS: Cardiac output
differed -0.04±0.52 l/min and myocardial displacement 0.1±0.5mm. Magnitude image contrast for myocardial displacement was visually lower in the post
contrast agent images. CONCLUSIONS: Acquisition of aortic flow is feasible both in the absence and presence of contrast agent. For myocardial
displacement phase-contrast data is assessable as such, but delineation not possible post contrast agent administration due to lower image contrast.
1363. Magnetic Resonance 2D Phase Contrast Flow Imaging of Patients with Stenotic Aortic and Pulmonary
Valves
Juha Ilmari Peltonen 1,2 , Touko Kaasalainen 3,4 , Sari Kivistö 3 , Miia Holmström 3 , Kirsi Lauerma 1
1 HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki, Finland; 2 Department of Biomedical Engineering and
Computational Science, Aalto University, Helsinki, Finland; 3 HUS Medical Imaging Center, Helsinki University Central Hospital,
N/A, Helsinki, Finland; 4 Department of Physics, Helsinki University, Helsinki, Finland
2D through plane phase contrast imaging of patients with stenotic pulmonal or aortic valves is subject to many sources of error. Accelerated flow speed
increases the amount and range of the acceleration artefact near the valve. On the other hand, the nature of the flow becomes highly turbulent soon after the
valve. In this study we have examined the effect of the mentioned error sources to measured net flow. Also, the optimal position of the measurement plane
and clinical routine currently in use is discussed.
1364. Validation of 4D Left Ventricular Blood Flow Assessment Using Pathlines
Jonatan Eriksson 1 , Petter Dyverfeldt 1 , Jan Engvall 1 , Ann F. Bolger 2 , Carl-Johan Carlhäll 1 , Tino Ebbers 1
1 Linköping University and Center for Medical Image Science and Visualization (CMIV), Linköping, Sweden; 2 University of
California San Francisco, San Francisco, CA, United States
A validation study of a pathline based left ventricular (LV) blood flow quantification approach is presented. The approach integrates morphological and
three-directional, three-dimensional cine phase-contrast MRI flow data, to separate the blood that transits the LV into four components. The validation
includes comparison of the LV outflow obtained from this approach to results from clinically applied methods of determining LV outflow: 2D through-plane
cine PC-MRI and Doppler ultrasound. Additionally inflow and outflow volumes obtained from the pathline based approach were compared.
1365. Blood Flow Patterns in the Left Ventricle of the Healthy Human Heart Described by Lagrangian
Coherent Structures Computed from 4D Phase Contrast MRI
Johannes Töger 1,2 , Johannes Ulén 1,3 , Marcus Carlsson 1 , Gustaf Söderlind 2 , Håkan Arheden 1 , Einar
Heiberg 1
1 Cardiac MR Group, Department of Clinical Physiology, Lund University Hospital, Lund, Sweden; 2 Numerical Analysis, Centre for
Mathematical Sciences, Lund University, Lund, Sweden; 3 Mathematical Imaging Group, Centre for Mathematical Sciences, Lund
University, Lund, Sweden
Blood flow patterns in the human heart are important for our understanding of cardiac pumping, and 4D phase contrast MRI may provide new insights.
However, the flow is complex, making it hard to visualize and understand. In this work, the flow patterns in the left ventricle are interpreted using
Lagrangian Coherent Structures, which reveal dynamically distinct compartments in the flow. Specifically, the inflow into the left ventricle is described in
four healthy volunteers.