Calculated T1 images derived from a partial saturation-inversion recovery pulse sequence with adiabatic fast passage

Abstract

Calculated T 1 images of the head and abdomen have been obtained using an alternating partial saturation-inversion recovery pulse sequence. Timing parameters were adjusted to yield optimum T 1 contrast-to-noise ratio for this sequence for the range of T 1 studied. Adiabatic fast passage (AFP) was implemented for the nonselective inverting pulse, to reduce the sensitivity of the measurement to RF and static field inhomogeneity. A nonlinear frequency sweep was used to improve the efficiency of the AFP pulse. The effect on the T 1 calculation of slice selection during the π 2 pulses was also determined and corrected for in the image reconstruction algorithm. The T 1's determined by this method show a standard deviation of < 10%, and good agreement with the literature.