Optimization of single shot 3D breath-hold non-enhanced MR angiography of the renal arteries

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 nonenhanced 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. © 2012 tan et al.; licensee biomed central ltd.