MRA和无创FAIR灌注成像在早期脑缺血中的诊断价值

为了探讨3D—TOFMRA脑血管成像及流动敏感交互式反转恢复（FAIR）MR灌注成像在早期（发病2h-7d）脑缺血中的诊断价值，对27例早期脑缺血患者行3D—TOFMRA和FAIR检查。结果显示，MRA异常27例，表现为血管闭塞、狭窄、硬化；FAIR异常27例，表现为缺血区血流灌注的减低，患侧和对侧灰、白质信号强度的差异均有统计学意义（P〈0．005），患者患侧与志愿者灰、白质信号强度的差异亦均有统计学意义（P〈0．005）。FAIR灌注技术无需注射造影剂，能够提供早期脑缺血患者血流动力学受损情况，FAIR与3D—TOF法MRA联合运用，对早期脑缺血的诊断、血流灌注评价会更全面、更准确。

Application of 3D -- TOF MRA and Non -- invasive FAIR MR Perfusion Technique in Cerebral Ischemia

To evaluate the diagnostic value of magnetic resonance angiography （MRA） and no--invasive flow--sensitive alternating inversion recovery （FAIR） MR perfusion technique in cerebral ischemia. 3D--TOF MRA and FAIR techniques were carried out in 27 cases of cerebral ischemia. Region of interest （ROI） analysis was performed in white matter and gray matter of ischemic side and contralateral side. 27 case were found the artery supplying the lesion on the MRA. 27 patients＇ perfusion images were successfully obtained. Mean signal intensity values were decreased in the white matter and gray matter of the hemisphere ipsilateral to the hypoperfusion side, as compared with values in the white matter and gray matter of the contralateral side （P〈0. 005 ） and with values in the white matter and gray matter of the control subjects （P 〈0. 005）. Being a technique for depicting cerebral perfusion without the requirement of exogenous contrast, FAIR can demonstrate the abnormal cerebral hemodynamic changes in cerebral ischemia. A combined use of 3D--TOF MRA and FAIR is useful in giving a more complete and correct evaluation of ischemia.