Doughty Christopher, Wang Jasmine, Feng Wuwei, Hackney David, Pani Ethan, Schlaug Gottfried
From the Neuroimaging and Stroke Recovery Laboratory, Department of Neurology (C.D., J.W., W.F., E.P., G.S.) and Department of Radiology (D.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA; and MUSC Stroke Center, Department of Neurology, Medical University of South Carolina, Charleston (W.F.).
Stroke. 2016 Jun;47(6):1520-6. doi: 10.1161/STROKEAHA.115.012088. Epub 2016 May 5.
A decrease in fractional anisotropy (FA) of the ipsilesional corticospinal tract (CST) distal to stroke lesions in the subacute (eg, 30 days) and chronic phase has been correlated with poor motor outcomes, but it is unclear whether FA values obtained within the acute stroke phase (here defined as 80 hours after onset) can predict later outcome.
Fifty-eight patients underwent an assessment of motor impairment in the acute phase and at 3 months using the upper extremity Fugl-Meyer assessment. FA values, obtained within 80 hours after stroke onset, were determined in 2 regions of interest: cerebral peduncle and a stretch of the CST caudal to each stroke lesion (nearest-5-slices).
The FA laterality index for the cerebral peduncle-regions of interest was a poor predictor of 3-month outcome (R(2)=0.044; P=0.137), whereas the slope over the FA laterality index of the nearest-5-slices showed a relatively weak but significant prediction (R(2)=0.11; P=0.022) with the affected side having lower FA values. Initial upper extremity Fugl-Meyer (R(2)=0.69; P<0.001) and the weighted CST lesion load (R(2)=0.71; P<0.001) were strong predictors of 3-month outcome. In multivariate analyses, controlling for initial upper extremity Fugl-Meyer, weighted CST lesion load, and days-of-therapy, neither the FA laterality index of the cerebral peduncle nor the slope over the FA laterality index of the nearest-5-slices significantly contributed to the prediction of 86% of the variance in the upper extremity Fugl-Meyer at 3 months.
FA reductions of the CST can be detected near the ischemic lesion in the acute stroke phase, but offer minimal predictive value to motor outcomes at 3 months.
在亚急性期（如30天）和慢性期，中风病灶远端同侧皮质脊髓束（CST）的分数 anisotropy（FA）降低与运动预后不良相关，但尚不清楚在急性中风期（此处定义为发病后80小时内）获得的FA值是否能预测后期预后。
58例患者在急性期和3个月时使用上肢Fugl-Meyer评估进行运动障碍评估。在中风发作后80小时内，在2个感兴趣区域测定FA值：大脑脚和每个中风病灶尾侧的一段CST（最近的5层切片）。
大脑脚感兴趣区域的FA侧性指数对3个月预后的预测能力较差（R(2)=0.044；P=0.137），而最近5层切片的FA侧性指数斜率显示出相对较弱但显著的预测能力（R(2)=0.11；P=0.022），患侧FA值较低。初始上肢Fugl-Meyer（R(2)=0.69；P<0.001）和加权CST病灶负荷（R(2)=0.71；P<0.001）是3个月预后的强预测指标。在多变量分析中，控制初始上肢Fugl-Meyer、加权CST病灶负荷和治疗天数后，大脑脚的FA侧性指数和最近5层切片的FA侧性指数斜率均未对3个月时上肢Fugl-Meyer 86%的方差预测有显著贡献。
在急性中风期，可在缺血病灶附近检测到CST的FA降低，但对3个月时的运动预后预测价值极小。
