Magnetization transfer contrast enhancement due to intermolecular multiple quantum coherences - quantitative analysis and tissue dependency

Introduction Recently published studies [1,2], showed an increased sensitivity of intermolecular multiple quantum coherences (iMQC) to magnetization transfer (MT) effects compared to single quantum coherences (SQC). The image contrast in magnetization transfer contrast (MTC) MRI is proportional to (Mz/M0) , where Mz is the actual longitudinal magnetization, M0 is the equilibrium magnetization and n denotes the order of the quantum coherence used (n=1 for SQC, n=2 for iDQC and so on). The aim of this work was to quantify this contrast enhancement and to determine the dependency of this effect on the tissue used. Experiments were performed on a 9.4-T animal scanner.