弥散张量成像参数FA值对急性颈髓损伤患者术后上肢运动功能恢复的预测价值

Predictive value of diffusion tensor imaging parameter fractional anisotropy in postoperative upper extremity motor function recovery in patients with acute cervical spinal cord injury

目的探讨弥散张量成像(DTI)参数对急性颈髓损伤(CSCI)患者术后上肢运动功能恢复的预测价值。方法选择解放军联勤保障部队第九OO医院神经外科自2019年5月至2021年7月手术后接受系统康复治疗的急性CSCI患者23例(试验组),另外选择该院体检中心同期与试验组患者年龄、性别相匹配的健康体检者22例(健康对照组)。术前1 d和术后3个月试验组患者均行颈髓MRI常规序列、DTI扫描及美国脊髓损伤协会(ASIA)评分、改良Barthe指数量表(MBI)评定。健康对照组受试者在入组后行颈髓MRI常规序列及DTI扫描。比较2组受试者颈髓损伤区、损伤区远端DTI参数,试验组患者手术前后DTI参数、上肢运动ASIA评分和MBI评分的差异。采用Pearson相关性分析检验试验组患者术前DTI参数与术前上肢运动ASIA评分、术后3个月上肢运动功能恢复率的相关性。采用受试者工作特征(ROC)曲线分析试验组患者术前各向异性分数(FA)值对术后3个月上肢运动功能恢复的预测效能。结果与健康对照组比较,试验组患者术前损伤区、损伤区远端FA值较低,表现弥散系数(ADC)值较高,差异均有统计学意义(P<0.05)。与损伤区远端比较,试验组患者术前损伤区FA值较低,ADC值较高,差异均有统计学意义(P<0.05)。与术前1 d比较,术后3个月试验组患者2个区域FA值、上肢运动ASIA评分及MBI评分较高,ADC值较低,差异均有统计学意义(P<0.05)。CSCI患者术前损伤区及损伤区远端FA值与术前上肢运动ASIA评分、术后3个月上肢运动功能恢复率呈正相关关系(P<0.05)。ROC曲线分析结果显示术前损伤区FA值预测术后3个月上肢运动功能恢复的曲线下面积(AUC)为0.912(95%CI:0.783~1.000,P<0.001);术前损伤区远端FA值预测术后3个月上肢运动功能恢复的AUC为0.842(95%CI:0.682~1.000,P<0.001)。结论DTI参数FA值和ADC值是检测CSCI的敏感指标;术前损伤区FA值和损伤区远端FA值均可用于预测上肢运动功能恢复,但前者的效能优于后者。

Objective To investigate the predictive value of diffusion tensor imaging(DTI)parameters in upper extremity motor function recovery after surgery in patients with acute cervical spinal cord injury(CSCI).Methods Twenty-three patients with acute CSCI who received postoperative systemic rehabilitation therapy in Department of Neurosurgery,900th Hospital of Joint Logistics Team of People's Liberation Army from May 2019 to July 2021 were selected as an experimental group,and 22 healthy subjects(healthy control group)matched with age and gender were selected from Physical Examination Center of the same hospital at the same period.Routine MRI sequence and DTI scan of the cervical spinal cord,scale of American Association for Spinal Cord Injury(ASIA)and modified Barthe index(mBI)were performed in patients of the experimental group 1 d and 3 months after surgery.Routine MRI sequence and DTI scan of the cervical spinal cord were performed in healthy subjects after enrollment.The DTI parameters in different regions between the two groups were compared,and the differences in DTI parameters,ASIA scores and mBI in patients of the experimental group before and after surgery were compared.Correlations of preoperative DTI parameters with preoperative upper extremity motor ASIA scores and upper extremity motor recovery rate 3 months after surgery were analyzed by Pearson correlation analysis.Receiver operating characteristic(ROC)curve was used to analyze the predictive efficacy of preoperative fractional anisotropy(FA)in upper extremity motor function recovery in CSCI patients 3 months after surgery.Results As compared with the healthy control group,the experimental group had significantly lower preoperative FA in the injury area and distal injury area,and statistically higher preoperative apparent diffusion coefficient(ADC,P<0.05).In patients of the experimental group,preoperative FA in the injury area was significantly lower and ADC in the injury area was significantly higher as compared with those in the distal injury area(P<0.05);patients of the experimental group had significantly higher FA in these two regions,upper extremity motor ASIA scores and mBI,and significantly lower ADC 3 months after surgery as compared with those 1 d before surgery(P<0.05).The preoperative FA in the injury area and distal injury area in CSCI patients were positively correlated with preoperative upper extremity motor ASIA scores and upper extremity motor recovery rate 3 months after surgery(P<0.05).ROC curve results showed that the area under the curve(AUC)of preoperative FA in injury area in predicting upper extremity motor function recovery 3 months after surgery was 0.912(95%CI:0.783-1.000,P<0.001);that of preoperative FA in the distal injury area was 0.842(95%CI:0.682-1.000,P<0.001).Conclusion DTI parameters FA and ADC are sensitive indicators for detecting CSCI;preoperative FA in the injury area and distal injury area can be used to predict the upper extremity motor function recovery,but the efficacy of the former is superior to that of the later.