磁共振弥散张量成像技术对颈髓急、慢性损伤的临床应用研究

目的探讨MR-DTI技术在颈髓急、慢性损伤临床应用的可行性及其诊断价值。方法收集病变组35例颈髓病变和对照组15例健康志愿者行常规MR及MR-DTI检查,分别测定各向异性分数(FractionalAnisotropy,FA)值、表观弥散系数(ApparentDiffusionCoefficient,ADC)值。结果正常人颈髓MR-DTI的FA值=0.657±0.058,ADC值=(0.958±0.136)×10-3mm2/s。颈髓慢性损伤MR-DTI的FA值=0.466±0.050,ADC值=(1.105±0.389)×10-3mm2/s;与对照组对比:颈髓慢性损伤中FA值明显降低,两者的差异有显著性(P0.05),而ADC值明显增高,两者的差异有显著性(P0.05)。结论 R-DTI可以探测到常规MRI上T2WI序列未能发现的颈髓慢性损伤病灶。所有病例通过DTI白质纤维束成像技术显示白质纤维束在病变区变形、移位及中断等改变,可为颈髓损伤程度的评估提供有价值的信息。

The Application of MR Diffusion Tensor Imaging in Acute and Chronic Cervical Cord Injury

Objective To investigate the feasibility of clinical application and diagnostic value of MR diffusion tensor imaging （MR-DTI） in cervical cord injury. Methods Total of 35 cases of cervical cord disorders and 15 healthy volunteers were selected prospectively. The scan sequences included conventional scans and DTI. The values of FA （Fractional Anisotropy） and ADC （Apparent Diffusion Coefficient） were measured by using Functool software. Results he FA and ADC values of the healthy controls were 0.657 ± 0.058 and （0.958 ± 0.136） × 10-3mm2/s respectively. Whereas, the FA and ADC values of patients with chronic cervical cord injury were 0.466±0.050 and（1.105 ± 0.389）×10 -3mm2/s. Compared with the control group, the chronic cervical cord injury cases had significantly lower FA values （P 0.05） and significantly higher ADC values （P 0.05）. Conclusion DTI can sensitively detect the chronic spinal cord injuries which the conventional T2-weighted images failed to reveal. The distortion, displacement and interruption of the white matter fiber tract in the cervical cord injury can be demonstrated by diffusion tensor tracking. MR-DTI can provide more valuable informa- tion to evaluate the severity of spinal cord injury.