In vivo measurement of a new source of contrast, the dipolar relaxation time, T1D, using a modified inhomogeneous magnetization transfer (ihMT) sequence

摘要: PURPOSE: This paper describes a technique that can be used in vivo to measure the dipolar relaxation time, T1D , of macromolecular protons contributing magnetization transfer (MT) tissues and produce quantitative maps. THEORY AND METHODS: The builds upon inhomogeneous MT (ihMT) is particularly sensitive tissue components with long . A standard ihMT experiment was altered introduce variable time for switching between positive negative offset frequencies RF saturation. model dependence developed fit data acquired vivo. RESULTS: Application method images from brains healthy volunteers produced values  = (5.9 ± 1.2) ms gray matter  = (6.2 ± 0.4) white regions provided maps parameter. CONCLUSION: experiments described provide access new characteristic potentially unique diagnostic information. Magn Reson Med, 2016. © 2016 International Society Magnetic Resonance Medicine.