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Abstract #1802

MR Sub-Sampling Strategies for Transcranial MRgFUS Applications

Henrik Oden1, 2, Nick Todd2, Mahamadou Diakite1, 2, Allison Payne2, Dennis L. Parker2

1Physics and Astronomy, University of Utah, Salt Lake City, UT, United States; 2Radiology, University of Utah, Salt Lake City, UT, United States

Three different k-space subsampling schemes were implemented in a 3D segmented EPI sequence for temperature measurements using the PRF shift method. The three schemes were evaluated by HIFU heating through a skull imbedded in an agar gel phantom. It is shown that sampling schemes with sequential sampling in the phase encode direction perform well, whereas sampling schemes with centric sampling underestimate temperatures, due to temperature induced frequency shifts resulting in a blurring effect of the focal spot.

Keywords

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