用相位敏感方法恢复信号极性的T1定量成像  

T1 mapping with polarity restoration by phase sensitive method

作　　者：朱海涛[1] 俎中良[1] 周堃[1] 俞燕明[1] 高嵩[2] 包尚联[1] 

机构地区：[1]北京大学医学物理和工程北京市重点实验室,北京100871 [2]北京大学医学部医学物理教研室,北京100083

出　　处：《中国医学影像技术》2007年第9期1397-1401,共5页Chinese Journal of Medical Imaging Technology

基　　金：国家自然科学基金科学仪器专项(10527003);国家自然科学基金面上项目(60672104);北京市教委共建项目(JD100010607);国家973项目(2006CB70570005);北京市自然科学基金项目(3073019);科技部科学仪器升级改造专项(2006JG1000)

摘　　要：目的研究相位敏感方法应用于T1定量测量的可行性及意义。方法采用相位敏感方法消除相位误差,保存反转恢复序列中磁化矢量的极性。再根据恢复后的图像数据的实部计算得到T1值图像。结果采用快自旋回波反转恢复序列得到了一组混合加权的幅度及相位图像,对其进行相位敏感校正后再做非线性最小二乘拟合,得到了体模的T1值及人体膝关节的T1图像。结论通过相位敏感方法保留极性信息的T1定量测量,在反转恢复序列成像中是可行的,并且具有较好的精确度。Objective To research on the feasibility and significance of the phase sensitive method in quantitive T1 measurement. Methods The phase sensitive method was used to remove the phase errors and restore the polarity of the inversion recovery data. Then the T1 values were calculated by the real part of the complex data in polarity restored images. Results A series of magnitude and phase images were collected by FSE-IR sequence, and the polarity information was restored using the phase sensitive method. T1 values of phantoms and Tl-map of a volunteer＇s knee were obtained by least square fitting. Conclusion The phase sensitive method is feasible for polarity restoration in T1 mapping using IR sequence, and it shows good accuracy.

关 键 词：磁共振成像 T1-map 极性恢复 相位敏感方法 

分 类 号：R445.2[医药卫生—影像医学与核医学]