脊髓型颈椎病颈髓与手术效果间关系的DTI研究

The DTI study on the relationship between structure of cervical cord and surgery outcome in cervical spondylotic myelopathy

目的:探讨扩散张量成像(DTI)对评价脊髓型颈椎病手术效果和脊髓术后恢复的应用价值。方法:纳入33例接受颈椎后路椎管扩大成型术治疗的脊髓型颈椎病患者,在术前和术后3个月分别进行常规MRI和DTI扫描,通过计算手术改善率将患者分为改善较好组(19例)和不好组(14例),比较两组患者最狭窄层面的术前各向异性分数(FA)、平均扩散率(MD)、轴向扩散率(AD)、纵向扩散率(RD)值的差异,分析术前DTI各参数值与改善率的相关性,比较术前与术后3个月DTI各参数值的变化。结果:较之改善不好组,改善较好组最狭窄层面的术前FA值较高,MD和RD值较低,差异均有统计学意义(FA值:Z=-2.315,P=0.021;MD值:Z=-2.114,P=0.035;RD值:Z=-2.295,P=0.022)。术前DTI各参数值与改善率不存在统计学意义上的相关性(FA、MD、AD、RD值的P值分别为0.527、0.608、0.082、0.753)。所有患者术后FA值较术前显著增高(t=-3.124,P=0.004),而MD、AD和RD值的变化则没有统计学意义(P值分别为0.331、0.307、0.103)。结论:DTI参数对评价手术预后有一定的应用价值,特别是FA值可在术后早期评价颈髓恢复情况。

Objective:To investigate the application value of diffusion tensor imaging(DTI)in the evaluation of surgery outcome and recovery in cervical spondylotic myelopathy.Methods:33 cervical spondylotic myelopathy(CSM)patients with posterior cervical laminoplasty were included in this study.Conventional MRI and DTI scans and clinical scoring were performed before and 3 months after surgery.Patients were divided into 2 groups(good-recovery and poor-recovery)by calculating the surgical improvement rate.Preoperative and postoperative DTI parameters,FA,MD,AD and RD,at the mostly compressed spot were measured.Results:Compared with the poor-recovery group,preoperative FA value in the good-recovery group was significantly higher,and the MD and RD values were significantly lower.But there was no statistical correlation between preoperative DTI metrics and recovery rate.Only the FA value was significantly increased 3 months after surgery.The changes in MD,AD and RD were not statistically significant.Conclusion:DTI has certain application value to evaluate surgery prognosis in cervical spondylotic myelopathy.And FA value may be a sensitive indicator for recovery evaluation in early stage after surgery.