脑转移瘤MRI序列的比较分析

Comparative analysis of MRI sequence in brain metastasis

目的比较常规MR T2WI/T1WI、液体衰减反转恢复序列及弥散加权成像检查技术对脑转移瘤的显示差异。方法对56例脑转移瘤患者在1.5 T的MR机上行常规MR T2WI/T1WI、DWI及FLAIR成像检查,设置肿瘤信噪比(signal to noise ratio,SNR)、正常脑实质SNR、肿瘤与周围脑脊液(cerebrospinal fluid,CSF)对比度(contrast,C)和对比噪声比(contrast to noise ratio,CNR)、肿瘤与周围正常脑实质C和CNR作为标准。结果病灶/脑脊液C方面,FLAIR序列优于常规MR T2WI/T1WI序列和DWI,有明显统计学意义(P<0.05)。病灶/脑脊液CNR、病灶/背景C及CNR、病灶SNR方面,常规MR T2WI优于其他序列,正常脑实质SNR常规MR T1WI优于其他序列,且均有统计学意义(P<0.05)。结论 FLAIR应作为颅内转移瘤重要的补充检查技术。

Objective To evaluate comprehensively the differential display of routine MR T2WI/T1WI,fluid attenuated inversion recovery（FLAIR） and diffusion weighted imaging（DWI） in evaluating the brain metastasis.Methods 56 patients were assessed on conventional MR T2WI/T1WI,FLAIR,DWI.The quantitative index was lesion/background contrast（C） and contrast-to-noise（CNR）,lesion/cerebrospinal fluid C and CNR,lesion signal/noise（SNR） and normal brain matter SNR.Results The lesion/cerebrospinal fluid C on FLAIR was significantly higher than those of other sequences（P〈0.05）.The lesion/background C and CNR,the lesion/cerebrospinal fluid CNR and the lesion SNR on routine T2WI were significantly higher than those of other sequences,the normal brain matter SNR on routine T1WI was significantly higher than those of other sequences（P〈0.05）.Conclusion FLAIR may be regarded as useful complementary techniques.