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Motion corrected intracranial MRA using PROPELLER with RF quadratic encoding

A new motion corrected Time‐of‐Flight MRA technique named Variable Pitch PROPELLER is presented. This technique employs the PROPELLER acquisition and reconstruction scheme for in‐plane bulk motion correction. A non‐ Fourier through‐plane encoding mechanism called quadratic encoding boosts SNR, relative to conventional 2D MRA, in lieu of traditional 3D encoding. Partial Fourier encoding is applied in the slice direction for a further reduction in scan time. This work details the construction and optimization of this technique. VPPROP MRAs are compared with a clinical MOTSA protocol. Initial results show promising robustness to bulk motion effects. The comparisons with MOTSA provide insight as to the additions required to create a comparable scan. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.