基于弥散张量纤维束成像探讨皮质脊髓束损伤对脑卒中运动功能障碍的评估价值

Assessment Value of Disrupted Corticospinal Tract Secondary to Stroke Lesion for Motor Impairment: A Diffusion Tensor Tracking Study

目的采用弥散张量纤维束成像技术(DTT)研究脑卒中皮质脊髓束(CST)损伤程度与运动功能障碍的关系。方法 2012年3月至2013年6月,采集15例慢性期左侧皮质下脑卒中患者(脑卒中组)和15例年龄、性别匹配的健康志愿者(健康对照组)的弥散张量成像(DTI)数据,运用DTT技术追踪CST,以健康对照组CST模板定量评估脑卒中病灶引起的CST损伤程度,并进一步与Fugl-Meyer评定量表(FMA)作相关性分析。结果脑卒中组的CST损伤值范围为0.00%～29.6%。脑卒中组CST损伤值与腕(r=-0.660, P=0.007)、手(r=-0.813, P <0.001)和腕+手(r=-0.795, P <0.001) FMA评分呈强负相关;与上肢(r=-0.614, P=0.015)和上肢+下肢(r=-0.563, P=0.029) FMA评分呈较强负相关;与下肢FMA评分无显著相关性(r=-0.270,P=0.331)。脑卒中病灶体积大小与各运动功能评分均无明显相关性(P> 0.05)。结论病灶对CST的直接累及程度与脑卒中运动功能损害程度密切相关。DTT定量计算CST损伤值可作为评估脑卒中患者上肢,尤其是手腕部运动功能障碍的一个潜在重要参考指标。

Objective To investigate the relationship between disrupted corticospinal tract(CST)and motor recovery after stroke by using diffusion tensor tracking(DTT).Methods From March,2012 to June,2013,15 chronic stroke patients with left subcortical lesions and 15 age-and sex-matched healthy subjects were performed diffusion tensor imaging(DTI)examination.The CST was tracked by DTT technique,and the damaged values of the CST caused by the stroke lesions were quantified using a CST template generated from healthy controls.Furthermore,the correlations of the damaged values of the CST with Fugl-Meyer Assessment(FMA)were performed.Results The range of the damaged values of CST in stroke patients was 0.00% to 29.6%.There were very strong negative correlation between the damaged values of the CST and FMA scores(the wrist,r=-0.660;hand,r=-0.813;wrist plus hand,r=-0.795,respectively,P<0.01).It also showed strong negative correlation between the damaged values of the CST and FMA scores(upper limb,r=-0.614;upper limb plus lower limb,r=-0.563,respectively,P<0.05).Whereas,there was no correlation between the damaged values of the CST and FMA scores of lower limb(r=-0.270,P=0.331).In addition,the lesion volumes of stroke and FMA scores were not significantly correlated(P>0.05).Conclusion The severity of motor deficit after stroke was closely related to the overlap of lesions with CST.The damaged values of the CST based on DTT may be used as a potential biomarker to assess motor impairments of upper limbs,especially hand and wrist in stroke patients.