A fast pulse sequence with spiral in-plane readout and conventional 3D partition encoding was reported for multiphase contrast-enhanced magnetic resonance angiography (CE-MRA) of the renal vasculature and compared to a standard multiphase 3D CE-MRA with FLASH readout . An isotropic in-plane spatial resolution of 1.4 x 1.4 mm2 over 2.0 x 1.4 mm2 could be achieved with a high temporal resolution. The theoretical gain of spatial resolution by using the spiral pulse sequence and the performance in the presence of turbulent flow was evaluated in phantom measurements. A deblurring technique corrected the spiral raw data. Thereby, the off-resonance frequencies were determined by
minimizing the imaginary part of the data in image space. The correction algorithm reduced image blurring substantially in all MRA phases (see Fig. 3.30). The image quality of the spiral CE-MRA pulse sequence was comparable to that of the FLASH CE-MRA with increased spatial resolution and a reduced contrast-to-noise ratio. Additionally, artifacts specific to spiral MRI could be observed that had no impact on the assessment of the renal arteries.
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