Optimization and Validation of a Constrained Reconstruction Algorithm for Rapid Whole-Brain Cross-Relaxation Imaging at 3.0 Tesla

Hunter R. Underhill¹, Chun Yuan¹, Vasily L. Yarnykh¹

Cross-relaxation imaging quantitatively maps the parameters describing magnetization transfer between free and bound protons in tissues. Whole-brain parametric maps of the fraction of macromolecular protons (f) and the rate constant (k) have been enabled at 1.5T by constraining the transverse relaxation time of both the free (T₂^F) and bound (T₂^B ) pools. We determine the optimized constraints for T₂^F and T₂^B to enable rapid, whole-brain parametric maps of f and k at 3.0T. In addition, we report the average values of f and k across various gray and white matter structures from a group of volunteers imaged at 3.0T.