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Magnetic resonance angiography of the body. Physical principles and technical challenges.

Methods for body MR angiography must contend with problems of motion, complex flow patterns and geometrics, and suppression of undesired material, while striving for adequate spatial resolution and signal-to-noise. Fortunately, MR offers a wide array of imaging options to tackle this formidable set of challenges, making this field an active area of research and development.