Diffusion-Weighted Double-Echo Magnetic Resonance Fingerprinting (MRF)

摘要

Apparatus, methods, and other embodiments associated with NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. Sampling is performed in response to a diffusion-weighted double-echo pulse sequence. Sampling acquires transient-state signals of the double-echo sequence. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals, and a characterization logic that characterizes a resonant species in the object as a result of comparing acquired signals to reference signals.

主权项

1. A method, comprising:
accessing a set of known signal evolutions; accessing an acquired nuclear magnetic resonance (NMR) signal, where the acquired NMR signal was produced by a volume that contains one or more resonant species that simultaneously produced individual NMR signals in response to magnetic resonance fingerprinting (MRF) excitation that employed a diffusion-weighted double-echo (DWDE) pulse sequence, where the acquired NMR signal includes a free induction decay (FID) signal and a spin echo signal; determining a signal evolution from the acquired NMR signal; finding a selected entry in the set of known signal evolutions that matches the signal evolution; retrieving, from stored MR parameters associated with the selected entry, quantitative values for T1 relaxation associated with the resonant species, T2 relaxation associated with the resonant species, an apparent diffusion coefficient (ADC) associated with the resonant species, and a proton density associated with the resonant species, T1 being spin-lattice relaxation, T2 being spin-spin relaxation, and simultaneously producing, from the quantitative values, quantitative maps associated with T1 relaxation associated with the resonant species, T2 relaxation associated with the resonant species, an apparent diffusion coefficient (ADC) associated with the resonant species, and a proton density associated with the resonant species.