Guillaume Duhamel1, Valentin H Prevost1, Gopal Varma2, David C Alsop2, and Olivier M Girard1
1CRMBM / CNRS 7339, Aix Marseille University, Marseille, France, 2Radiology, Division of MR Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
The
inclusion of a dipolar reservoir in the existing two pool model for MT allowed interpreting
the inhomogeneous MT (ihMT) signal as a dipolar order effect -characterized by
a relaxation time T1D - within
motion restricted molecules.
In
this study, we demonstrate that an ihMT signal can actually be evidenced in any
component with non-trivial T1D
value. Adjustment of the dual frequency irradiation efficiency by increase of Δt, the repetition rate of
consecutive saturation pulses, filters the signal of shorter T1D components.
This provides a means to realize T1D-weighted
imaging, a new source of MR contrast between tissues.