- Poster presentation
- Open Access
High-dose dobutamine stress SSFP cine MRI at 3 Tesla with patient adaptive local RF shimming using dual-source RF transmission
© Berger et al; licensee BioMed Central Ltd. 2012
- Published: 1 February 2012
- Image Quality
- Steady State Free Precession
- Invasive Coronary Angiography
- Severe Artifact
- Steady State Free Precession Sequence
Image quality of cine imaging using steady state free precession (SSFP) sequences at 3T is insufficient due to increased RF-inhomogeneity (B1 field) and the high sensitivity of SSFP sequences to off-resonance artefacts. Recently, the introduction of a dual source RF transmission system with patient-adaptive local RF-shimming has led to a significant improvement of image quality of SSFP imaging at 3T.
The objective of this study was to prospectively evaluate the feasibility, image quality and diagnostic accuracy of high-dose dobutamine stress magnetic resonance imaging (DSMR) at 3T comparing dual-source versus single-source transmit technology.
DSMR was performed in 44 patients with each participant undergoing cine imaging at rest and during dobutamine infusion using both dual- and single-source transmit technology.
B1-maps and measurements of contrast to noise ratio (CNR) were evaluated to quantify the effect of RF calibration in both transmission modes.
Analysis of image quality (0=non diagnostic, 1=severe artifact, 2=slight artifact, 3=no artifact) and wall motion was performed at rest and at maximum stress comparing single- and dual-source technology.
CAD was defined on invasive coronary angiography as the presence of ≥70% stenosis.
The mean percentage of the intended flip angle within the heart increased from 88% ± 9.1 with single-source to 103% ± 5.6 with dual-source (p<0.001). Deviation of the flip angle from the base to the apex along the pseudo-long axis decreased from 29.8% ± 12.9% with single-source to 12.8% ± 7.2% with dual-source.
CNR increased for dual-source vs. single-source especially pronounced at the apex (63.4 ± 24.2 vs. 36.5 ± 16.5, p<0.001) but also at the base (50.1 ± 14.8 vs. 39.3 ± 15.8, p<0.001).
We demonstrated that using a dual-source transmit technology in a standard DSMR protocol is feasible in a 3T environment. Furthermore, the dual-source transmit technology provides better image quality and higher diagnostic accuracy compared to single-source transmit technology.
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.