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 k_T-points pulses to pre-compensate B₁⁺ heterogeneity in the context of brain T₁ mapping with DESPOT1. The use of k_T-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.