High-resolution magnetic resonance angiography of the renal arteries using parallel imaging acquisition techniques at 3.0 T: Initial experience

OBJECTIVE: The purpose of this prospective study was to investigate the feasibility of high-resolution magnetic resonance angiography (MRA) of the kidneys at 3.0 T using parallel data acquisition. MATERIAL AND METHODS: Contrast-enhanced MRA of the renal arteries (RA) was performed in 12 volunteers and 12 consecutive patients (mean age 47.1 ± 16.3 years) on a 3.0 T MR scanner. For CEMRA, a high-resolution 3-dimensional GRE FLASH sequence was implemented. Images were assessed subjectively on a 0 to 5 scoring scale by 2 reviewers. Quantitative evaluation was done by measuring the contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). RESULTS: Diagnostic image quality was acquired in all individuals. In total, 62 RA were found, consisting of 48 main and 14 accessory RA. Overall visibility score for main RA was 4.82 ± 0.38. RA were identified up to the third-order branches in 88%. In 3 of 12 patients, a hemodynamic relevant stenosis was found and proven by conventional angiogram. CONCLUSION: CEMRA at 3.0 T is advantageous in terms of better SNR and T1 weighting; therefore, measurement time can be reduced and spatial resolution can be increased without corruption of signal yield. Consequently, high-field MRA may be preferred for the evaluation of renal vascular anatomy in potential kidney donors or for the detection of renal artery stenosis.