Department of Psychology, University of Surrey, Guildford, United Kingdom.
Neurorehabil Neural Repair. 2010 Jun;24(5):413-9. doi: 10.1177/1545968309348310.
With diffusion-tensor imaging (DTi) it is possible to estimate the structural characteristics of fiber bundles in vivo. This study used DTi to infer damage to the corticospinal tract (CST) and relates this parameter to (a) the level of residual motor ability at least 1 year poststroke and (b) the outcome of intensive motor rehabilitation with constraint-induced movement therapy (CIMT).
To explore the role of CST damage in recovery and CIMT efficacy.
Ten patients with low-functioning hemiparesis were scanned and tested at baseline, before and after CIMT. Lesion overlap with the CST was indexed as reduced anisotropy compared with a CST variability map derived from 26 controls. Residual motor ability was measured through the Wolf Motor Function Test (WMFT) and the Motor Activity Log (MAL) acquired at baseline. CIMT benefit was assessed through the pre-post treatment comparison of WMFT and MAL performance.
Lesion overlap with the CST correlated with residual motor ability at baseline, with greater deficits observed in patients with more extended CST damage. Infarct volume showed no systematic association with residual motor ability. CIMT led to significant improvements in motor function but outcome was not associated with the extent of CST damage or infarct volume.
The study gives in vivo support for the proposition that structural CST damage, not infarct volume, is a major predictor for residual functional ability in the chronic state. The results provide initial evidence for positive effects of CIMT in patients with varying, including more severe, CST damage.
通过弥散张量成像（DTi）可以估计活体纤维束的结构特征。本研究使用 DTi 推断皮质脊髓束（CST）的损伤，并将该参数与（a）卒中后至少 1 年的残余运动能力和（b）强制性运动疗法（CIMT）的强化运动康复的结果相关联。
探讨 CST 损伤在恢复和 CIMT 疗效中的作用。
10 名运动功能低下的偏瘫患者在基线、CIMT 前后进行扫描和测试。与从 26 名对照中得出的 CST 变异性图相比，病变与 CST 的重叠表现为各向异性降低。基线时通过 Wolf 运动功能测试（WMFT）和运动活动日志（MAL）测量残余运动能力。通过 WMFT 和 MAL 治疗前后的比较评估 CIMT 获益。
CST 与病变重叠与基线时的残余运动能力相关，CST 损伤越广泛，患者的缺陷越大。梗塞体积与残余运动能力无系统关联。CIMT 导致运动功能显著改善，但结果与 CST 损伤程度或梗塞体积无关。
本研究为 CST 结构损伤而非梗塞体积是慢性状态下残余功能能力的主要预测因素这一观点提供了体内支持。结果为 CIMT 在包括更严重 CST 损伤在内的不同损伤患者中的积极作用提供了初步证据。
