NMR IMAGING DEVICE AND NMR IMAGING METHOD

摘要

In order to provide an NMR imaging device capable of distinguishing substances that cannot be distinguished by T2H, an NMR imaging device (1) according to this invention includes: a probe (3) capable of housing a sample in a static gradient magnetic field; an application portion (5) configured to apply a π pulse having a Larmor frequency corresponding to the static gradient magnetic field at a predetermined position of the sample to the sample in a multiplexed manner at a predetermined time interval; and an image processing portion (7) configured to determine a relaxation time based on a nuclear magnetic resonance signal of the sample, and perform imaging of the relaxation time.

主权项

1. An NMR imaging device, comprising:
a probe capable of housing a sample in a static gradient magnetic field; an application portion configured to apply a π pulse to the sample in a multiplexed manner at a predetermined time interval, the π pulse having a Larmor frequency corresponding to the static gradient magnetic field at a predetermined position of the sample; and an image processing portion configured to determine a transverse relaxation time based on converged attenuation characteristics of a nuclear magnetic resonance (NMR) signal of the sample obtained when multiple pulses are applied, and perform imaging of the transverse relaxation time, the NMR signal and the transverse relaxation time having a relationship shown in the following expression (1), the predetermined time interval of the π pulse and a frequency of noise received by the sample from an external environment being expressed by the following expression (2), wherein the NMR imaging device is configured so as to: determine a predetermined time interval 2τ of the π pulse based on a frequency f of noise received by a nuclear spin in the expression (2) by utilizing a fact that the transverse relaxation time determined from the expression (1) indicates an amplitude of the noise corresponding to the frequency having a relationship of the expression (2) with the predetermined time interval of the π pulse; measure the NMR signal at the predetermined time interval 2τ of the π pulse; and determine an attenuation curve of intensity of the NMR signal based on a measurement result of the NMR signal, thereby determining the transverse relaxation time (T2L) based on the expression (1).
W(t)˜exp(−t/T2L)  (1) W(t): NMR signal intensity T2L: signal attenuation constant (transverse relaxation time) t: timef=14τ(2) f: frequency of noise received by nuclear spin τ: (a half of) π pulse interval.