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Abstract #2211

kT-Points RF Pulses for Pre-Compensation of B1+ Heterogeneity in DESPOT1

Ives R. Levesque1, Jason Su2, Mohammad Mehdi Khalighi3, John M. Pauly1, Brian K. Rutt2

1Electrical Engineering, Stanford University, Stanford, CA, United States; 2Radiology, Stanford University, Stanford, CA, United States; 3Global Applied Science Laboratory, GE Healthcare, Menlo Park, CA, United States

The method of driven-equilibrium single-pulse observation of T1 relaxation (DESPOT1) is a method which provides fast volumetric T1 mapping, but is notoriously dependent on flip angle calibration. We propose to use kT-points pulses to pre-compensate B1+ heterogeneity in the context of brain T1 mapping with DESPOT1. The use of kT-points pulses resulted in improved B1+ homogeneity, which translated to improved homogeneity in the volumetric T1 map. T1 variability in brain white matter was reduced in the by a factor of 1.2 and range by a factor of 1.4.

Keywords

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