- Poster presentation
- Open Access
Free-breathing non-contrast MRA with efficiency-adaptive self navigation
© Xie et al; licensee BioMed Central Ltd. 2013
- Published: 30 January 2013
- Renal Artery
- Projection Profile
- Comparable Image Quality
- Saturation Band
- Navigator Gating
Non-contrast MRA (NC-MRA) based on bSSFP and slab-selective inversion has become an attractive alternative for imaging renal arteries without the usage of potentially nephrotoxic contrast agent. It typically requires navigator gating or abdominal bellow triggering to alleviate breathing motion artifacts. However, navigator gating significantly complicates and lengthens exams due to its setup, adjusting, and scout scans. It also causes signal loss in renal arteries due to cross-pair saturation bands. Abdominal bellow triggering increases patient preparation time and disables the usage of ECG triggering leading to suboptimal inflow effect. In this work, a novel self navigation (SN) technique is developed in an attempt to overcome the limitations of the aforementioned free-breathing methods while maintaining scanning efficiency.
Nine healthy volunteers with IRB approval were scanned on a 3T clinical scanner (MAGNETOM Verio, Siemens) with the following scan parameters: repetition = 700-900 ms; TI = 550-750 ms; acquisition time = 4-6 min depending on subject heart rate; TE/TR = 1.9/3.8 ms; 3D transverse slab with left-right readout; FOV = 400x250 mm2, matrix = 304x192, slice thickness = 2.2 (1.1 interpolated) mm, yielding isotropic resolution = 1.1 mm3; iPAT = 2; bandwidth = 780 Hz/pixel; FA = 90. For comparison, conventional navigator gated bSSFP MRA images were acquired immediately afterwards using same parameters.
Preliminary results of SN bSSFP NC-MRA have demonstrated comparable image quality to conventional navigator gated acquisition but much simplified imaging planning and absence of saturation bands. Its performance in patients is currently under investigation.
This work is funded by grant NIH/NHLBI R01HL096119
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.