PERFIDI (Parametrically Enabled Relaxation FIlters with Double and multiple Inversion) is an experimental NMR/MRI technique devised to analyze samples/voxels characterized by multi-exponential longitudinal relaxation. It is based on a linear combination of NMR sequences with suitable preambles composed of inversion pulses. Given any standard NMR/MRI sequence, it permits one to modify it in a way which will attenuate, in a predictable manner and before data acquisition, signals arising from components with different r rates (r = 1/T1). Consequently, it is possible to define relatively simple protocols to suppress and/or to quantify signals of different components. This article describes a simple way to construct low-pass, high-pass and band-pass PERFIDI filters. Experimental data are presented in which the method has been used to separate fat and water proton signals. We also present a novel protocol for very fast determination of the ratio between the fat signal and the total signal which avoids any time-consuming magnetization recovery multi-array data acquisition. The method has been validated also for MRI, producing well T1-contrasted images.
V. Bortolotti, P. Fantazzini, M. Gombia, D. Greco, G. Rinaldin, S. Sykora (2010). PERFIDI filters to suppress and/or quantify relaxation time components in multicomponent systems: an example for fat-water systems. JOURNAL OF MAGNETIC RESONANCE, 206, 219-226 [10.1016/j.jmr.2010.07.010].
PERFIDI filters to suppress and/or quantify relaxation time components in multicomponent systems: an example for fat-water systems
BORTOLOTTI, VILLIAM;FANTAZZINI, PAOLA;GOMBIA, MIRKO;
2010
Abstract
PERFIDI (Parametrically Enabled Relaxation FIlters with Double and multiple Inversion) is an experimental NMR/MRI technique devised to analyze samples/voxels characterized by multi-exponential longitudinal relaxation. It is based on a linear combination of NMR sequences with suitable preambles composed of inversion pulses. Given any standard NMR/MRI sequence, it permits one to modify it in a way which will attenuate, in a predictable manner and before data acquisition, signals arising from components with different r rates (r = 1/T1). Consequently, it is possible to define relatively simple protocols to suppress and/or to quantify signals of different components. This article describes a simple way to construct low-pass, high-pass and band-pass PERFIDI filters. Experimental data are presented in which the method has been used to separate fat and water proton signals. We also present a novel protocol for very fast determination of the ratio between the fat signal and the total signal which avoids any time-consuming magnetization recovery multi-array data acquisition. The method has been validated also for MRI, producing well T1-contrasted images.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.