增强 T1- FLAIR 序列和磁化传递对比技术诊断脑微小转移瘤

目的：对比分析增强 T1液体衰减反转恢复（T1- FLAIR）序列和磁化传递对比（MTC）两种序列对脑内微小转移瘤的应用价值。方法：对60例患有脑转移瘤的病人行常规扫描后采用 T1- FLAIR 和 T1 WI ＋ MTC序列增强扫描，分别统计增强后 T1- FLAIR 和 T1 WI ＋ MTC 序列显示转移瘤的数目、大小、位置等，并比较二者对微小转移瘤的显示能力及2种序列图像的病灶-背景的对比度/噪声（C/ Ns）值。结果：60例脑转移瘤中，共计235个病灶，增强后 MTC 序列显示了231个病灶，显示率为98.3%，T1- FLAIR 序列显示了227个病灶，显示率为96.6%。T1 WI ＋ MTC 序列发现了 T1- FLAIR 序列不能显示的4个病灶，而 T1- FLAIR 序列证实了 T1 WI ＋ MTC 序列误判的2个病灶。T1 WI ＋ MTC 图像病灶-背景的 C/ Ns 值为29.85±6.43，T1- FLAIR图像病灶-背景的 C/ Ns 值为14.54±7.64，T1 WI ＋ MTC 序列的 C/ Ns 值高于 T1- FLAIR 序列的 C/ Ns 值（t=7.05，P ﹤0.05）。结论：增强 T1 WI ＋ MTC 序列和增强 T1- FLAIR 序列相互补充，二者结合能够最大程度满足微小转移瘤的显示和鉴别诊断的需要。

Application value of contrast - enhanced T1 - FLAIR and MTC in the intracranial micro-metastases

Objective:To analyze the application value of contrast - enhanced T1 fluid attenuated inversion recov-ery(T1 - FLAIR)and Magnetic transfer contrast(MTC)in the intracranial micrometastases. Methods:All 60 patients with intracranial metastases received MRI plain routine scans and contrast - enhanced T1 - FLAIR and T1 WI + MTC scans. The numbers,size,and location of metastases were analyzed and the display abilities of two sequences for mi-crometastases and contrast - to - noise ratio(C/ Ns)of lesion - background on T1 - FLAIR and T1 WI + MTC images were compared. Results:Total of 235 lesions were demonstrated in 60 patients with intracranial metastases. MTC ima-ges showed 231 lesions(98. 3% ),while T1 - FLAIR showed 227 lesions(96. 6% ). T1 WI + MTC discovered 4 lesions which T1 - FLAIR cannot display. And T1 - FLAIR verified 2 lesions misjudged by MTC. C/ Ns of lesion - background on T1 WI + MTC images(29. 85 ± 6. 43)is higher than C/ Ns on T1 - FLAIR images(14. 54 ± 7. 64)(t = 7. 05,P ﹤0. 05). Conclusion:Contrast - enhanced T1 - FLAIR and T1 WI + MTC become complementary,and the combination of two sequences can mostly satisfy the display of micrometastases and requirements of differential diagnosis.