关于MRI反转恢复技术中图像对比度反转现象的研究

Study of the phenomenon of reverse imaging contrast in MRI inversion recovery technology

目的 :研究造成图像对比度反转现象的原因。方法 :从理论上对核磁共振成像反转恢复技术进行系统研究 ,获得不同组织之间对比度CAB=0时 ,恢复时间TI0 所满足的数学表达式。结果 :零对比度时 ,恢复时间TI0 所满足的数学表达式是。结论 :在脉冲序列重复时间TR 一定时 ,恢复时间TI 的取值范围决定了是否会出图像对比度反转现象。

Objective: To study the reason why the phenomenon of reverse image contrast is caused. Methods:To study the MRI inversion recovery technology systemically in theory and get the mathematical expression of recovery time TI0 when the contrast between different tissue is zero. Results:When the contrast is zero,the mathematical expression of recovery time TI0 is: .Conclusion: When the pulse sequence repetition time TR is set, whether existing the phenomenon of reverse imaging contrast depend on the selective range of recovery time TI0.