发明名称 |
MRI method and apparatus for selective image suppression of material based on T1 and T2 relation times |
摘要 |
The selective imaging of an object having two materials with different relaxation times (T1 or T2) is provided by using a driven equilibrium sequence (T2 weighted preparation sequence) followed by an inversion recovery sequence. In the driven equilibrium sequence the object is placed in a static magnetic field along a longitudinal axis, an excitation pulse is applied to tip nuclei spins into a transverse plane, and at least one refocusing pulse is applied to produce a spin echo having a magnetization component as a function of relaxation time. At least one pulse is then applied to the object to drive the spin echo to an inverted position along the longitudinal axis. A readout excitation is then applied at a later time when the longitudinal magnetization of one material is substantially reduced. In one embodiment, an inversion pulse is applied prior to the T2 weighted preparation sequence.
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申请公布号 |
US5655531(A) |
申请公布日期 |
1997.08.12 |
申请号 |
US19950441101 |
申请日期 |
1995.05.15 |
申请人 |
THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIVERSITY |
发明人 |
NISHIMURA, DWIGHT G.;BRITTAIN, JEAN H. |
分类号 |
A61B5/055;G01R33/50;(IPC1-7):A61B5/055 |
主分类号 |
A61B5/055 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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