DWI及SWI序列对弥漫性轴索损伤的诊断价值

目的探讨弥散加权（DWI）和磁敏感加权（SWI）序列在脑弥漫性轴索损伤（DAI）中的诊断价值。方法回顾性分析17例经临床和影像证实的急性DAI患者的MRI资料，包括常规T1WI、T2WI、液体衰减反转恢复（FLAIR）序列以及DWI和SWI序列，分别比较各序列对DAI非出血性和出血性病灶的检出数目，并分析其分布特点和信号特征。结果DAI病灶主要分布在白质、皮髓交界区、基底节、胼胝体、脑干及小脑等区域。DWI对非出血性DAI病灶的检出率最高，与其它序列的差异有统计学意义（P〈0．05）。而SWI对出血性DAI病灶的检出率最高，与其它序列的差异也均有统计学意义（P〈0．05）。结论DWI和SWI序列联合应用大大提高DAI病灶的检出率，为临床早期诊断提供更加可靠的影像学依据，应作为MRI检查DAI的常规和首选序列。

Value of DWI and SWI in the diagnosis of diffuse axonal injury

Objective To investigate the value of diffusion weighted imaging （DWI） and susceptibility weighted imaging （SWI） in the diagnosis of diffuse axonal injury （DAI）. Methods MRI data of 17 cases with acute diffuse axonal injury proved by clinical manifestation and imaging were retrospectively analyzed. MRI data included T1 WI, T2 WI, fluid attenuated inversion recovery （FLAIR）, DWI and SWI sequences. The detected number of lesions was compared among the different sequences. The characteristics of signal and distribution of lesions were analyzed. Results DAI lesions located in the white matter, junctional zone of cortex and medulla, basal ganglia, corpus callosum, brain stem and cerebellum. The detected number of non-hemorrhagic lesion on DWI was the highest and significantly higher than that on other sequences （P 〈0.05）. The detected number of hemorrhagic lesion on SWI was the highest and significantly higher than that on other sequences （P 〈0.05）. Conclusion Combination of DWI and SW/can improve detection ratio of DAI lesions, providing more image evidence for early clinical diagnosis, so DWI and SWI should be the first and routine sequence in the MRI examination of DAI detection.