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Abstract #3387

Point Spread Function (PSF) Map Technique for Distortion Correction of Echo Planar Imaging (EPI) at 7T

Yu Cai1, Mark Woods1, John Grinstaed2, William Rooney1, Xin Li1, Qingwei Liu3, Craig Hamilton4, Hongyu An5

1Oregon Health&Science University, Portland, OR, United States; 2Siemens Healthcare, U.S.A; 3Barron Neurological Institure, Phonenix, AZ, United States; 4Wake Forest University; 5University of North carolina

Point spread function (PSF) mapping method has been proposed to correct for the geometric distortion. We further developed the PSF mapping technique using the regularized inverse solution and dual echo acquisition strategy for EPI distortion correction at 3.0T, in which the first EPI readout serve the PSF mapping and the second EPI readout is the actual EPI acquisition Its advantage is no need of the extra scan time to acquire the PSF map. With the rapidly expanding interest of fMRI study in utilizing ultra high field system, it becomes urgent to develop a robust EPI distortion correction scheme at 7.0T. We attempted to apply PSF mapping technique developed in 3.0T to test its correction efficacy at 7.0T.

Keywords

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