Technical notes
Optimization of single shot 3D breath-hold non-enhanced MR angiography of the renal arteries
1 Department of Radiology, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL, 60201, USA
2 The University of Chicago Pritzker School of Medicine, Chicago, IL, USA
3 Siemens Healthcare, Cardiovascular MR R&D, Chicago, IL, USA
4 Northwestern University Feinberg School of Medicine, Chicago, IL, USA
Journal of Cardiovascular Magnetic Resonance 2012, 14:30 doi:10.1186/1532-429X-14-30
Published: 19 May 2012Abstract
Background
Cardiac and navigator-gated, inversion-prepared non-enhanced magnetic resonance angiography techniques can accurately depict the renal arteries without the need for contrast administration. However, the scan time and effectiveness of navigator-gated techniques depend on the subject respiratory pattern, which at times results in excessively prolonged scan times or suboptimal image quality. A single-shot 3D magnetization-prepared steady-state free precession technique was implemented to allow the full extent of the renal arteries to be depicted within a single breath-hold.
Methods
Technical optimization of the breath-hold technique was performed with fourteen healthy volunteers. An alternative magnetization preparation scheme was tested to maximize inflow signal. Quantitative and qualitative comparisons were made between the breath-hold technique and the clinically accepted navigator-gated technique in both volunteers and patients on a 1.5 T scanner.
Results
The breath-hold technique provided an average of seven fold reduction in imaging time, without significant loss of image quality. Comparable single-to-noise and contrast-to-noise ratios of intra- and extra-renal arteries were found between the breath-hold and the navigator-gated techniques in volunteers. Furthermore, the breath-hold technique demonstrated good image quality for diagnostic purposes in a small number of patients in a pilot study.
Conclusions
The single-shot, breath-hold technique offers an alternative to navigator-gated methods for non-enhanced renal magnetic resonance angiography. The initial results suggest a potential supplementary clinical role for the breath-hold technique in the evaluation of suspected renal artery diseases.
