液体衰减翻转恢复序列在颅脑MRI中的应用

目的：探讨１．５ＴＭＲ颅脑液体衰减翻转恢复（ＦＬＡＩＲ）序列的合理扫描参数及其临床应用价值。材料和方法：首先对１８名健康志愿者行１．５ＴＭＲ的颅脑ＦＬＡＩＲ序列的参数选择试验，然后用筛选出的合理参数对２４例脑部疾病患者行ＦＬＡＩＲ序列与ＳＥ序列的对照扫描。结果：在１．５ＴＭＲ颅脑ＦＬＡＩＲ扫描中，当ＴＲ＝６０００ｍｓ时，ＴＩ为１７００－１８００ｍｓ接近脑脊液的无效值，ＴＥ以１６０ｍｓ为宜。ＦＬＡＩＲ序列与ＳＥ序列的对照扫描中，ＦＬＡＩＲ序列显示病变为７５／７６（９８．６８％），ＳＥ序列为６５／７６（８５．５３％），两者显示病变的敏感度有显著性差异（Ｐ＜０．０１）。结论：ＦＬＡＩＲ序列对靠近脑脊液的病变、脑组织水肿、室管膜下漏液、脑室和脑池内病变的检出较ＳＥ序列更敏感。

Use of Fluid Attenuated Inversion Recovery (FLAIR)Pulse Sequence in MRI of the Brain

To evaluate the role of FLAIR(Fluid Attenuated Inversion Recovery) pulse sequence in 1.5T MRI of the brain and to select the appropriate parameters of this pulse sequence. Materials and Methods : 18 healthy volunteers were chosen to perform brain scanning on a GE 1.5T MRI unit,applying FLAIR sequence,to obtain the suitable parameters. Then 24 patients with brain diseases were studied employing FLAIR and SE sequences respectively,Results: The study showed that on a 1.5T MRI unit, for brain scanning. The appropriate TI of FLAIR sequence is about 1700-1800ms,which is approximately the null point for CSF, TE of 160ms is more preferable.Comparing the results of these two sequences, we found that lesions were more easily detected with FLAIR 75/76(98.68%)than with SE 65/76(85.53%). The difference is statistically significant (P< 0.01). Conclusion: FLAIR is superior to SE sequences in identifing lesions close to CSF, edema of brain tissue. subendymal transudate, intracistrenal and intraventricular lesions.