公开(公告)号：US5682891A

公开(公告)日：1997-11-04

申请号：US450956

申请日：1995-05-23

申请人： Kiyohito Sonoki ,  Takihito Sakai

发明人： Kiyohito Sonoki ,  Takihito Sakai

IPC分类号： G01R33/46 ,  A61B5/055 ,  G01R33/36 ,  G01R33/48 ,  G01R33/563

CPC分类号： G01R33/563 ,  G01R33/3607 ,  G01R33/446 ,  G01R33/5605

摘要： An MR imaging apparatus using NMR phenomenon includes a main magnet, a first, a second and a third gradient field coils, a RF coil, a gradient field controller connected to the first, second and third gradient field coils, a RF controller connected to the RF coil, a waveform generator, a carrier wave generator, an amplitude modulator, a RF controller connected to the RF coil, and a data processor. The waveform generator generates a modulating signal expressed by F(t)=A {cos (.omega.t)-cos (E.omega.t)}/t, where A is an amplitude coefficient, .epsilon. is a non-excitation band coefficient, and .omega. is a frequency of the modulating signal. The RF controller causes the RF coil, in each pulse sequence, to transmit a RF signal and to apply, to the RF signal, a modulated wave output from the amplitude modulator as an MTC pulse having a frequency component slightly offset from a resonance frequency of free water protons, and a resonance frequency component of free water protons. The data processor collects data from the NMR signal detected by the RF coil, and reconstructs a sectional image from the data.

摘要翻译： 使用NMR现象的MR成像装置包括主磁体，第一，第二和第三梯度场线圈，RF线圈，连接到第一，第二和第三梯度场线圈的梯度场控制器，连接到 RF线圈，波形发生器，载波发生器，幅度调制器，连接到RF线圈的RF控制器和数据处理器。 波形发生器产生由F（t）= A {cos（ωω）-cos（Eωt）} / t表示的调制信号，其中A是振幅系数，ε是非激励频带系数，ω 是调制信号的频率。 RF控制器使得RF线圈在每个脉冲序列中传输RF信号并且将RF调制波输出的调制波作为MTC脉冲施加到具有稍微偏离谐振频率的频率分量的MTC脉冲 游离水质子和自由水质子的共振频率分量。 数据处理器从由RF线圈检测的NMR信号收集数据，并从数据中重建截面图像。