Stewart Jill Campbell, Dewanjee Pritha, Tran George, Quinlan Erin Burke, Dodakian Lucy, McKenzie Alison, See Jill, Cramer Steven C
Program in Physical Therapy, Department of Exercise Science, University of South Carolina, Columbia, SC 29208, USA.
Departments of Neurology and Anatomy & Neurobiology, University of California, Irvine, CA 92697, USA.
Neuroimage Clin. 2017 Mar 2;14:641-647. doi: 10.1016/j.nicl.2017.02.023. eCollection 2017.
While the corpus callosum (CC) is important to normal sensorimotor function, its role in motor function after stroke is less well understood. This study examined the relationship between structural integrity of the motor and sensory sections of the CC, as reflected by fractional anisotropy (FA), and motor function in individuals with a range of motor impairment level due to stroke. Fifty-five individuals with chronic stroke (Fugl-Meyer motor score range 14 to 61) and 18 healthy controls underwent diffusion tensor imaging and a set of motor behavior tests. Mean FA from the motor and sensory regions of the CC and from corticospinal tract (CST) were extracted and relationships with behavioral measures evaluated. Across all participants, FA in both CC regions was significantly decreased after stroke ( < 0.001) and showed a significant, positive correlation with level of motor function. However, these relationships varied based on degree of motor impairment: in individuals with relatively less motor impairment (Fugl-Meyer motor score > 39), motor status correlated with FA in the CC but not the CST, while in individuals with relatively greater motor impairment (Fugl-Meyer motor score ≤ 39), motor status correlated with FA in the CST but not the CC. The role interhemispheric motor connections play in motor function after stroke may differ based on level of motor impairment. These findings emphasize the heterogeneity of stroke, and suggest that biomarkers and treatment approaches targeting separate subgroups may be warranted.
虽然胼胝体（CC）对正常的感觉运动功能很重要，但其在中风后运动功能中的作用尚不太清楚。本研究探讨了以分数各向异性（FA）反映的CC运动和感觉部分的结构完整性与因中风导致不同运动障碍水平个体的运动功能之间的关系。55名慢性中风患者（Fugl-Meyer运动评分范围为14至61）和18名健康对照者接受了扩散张量成像和一组运动行为测试。提取了CC运动和感觉区域以及皮质脊髓束（CST）的平均FA，并评估了其与行为指标的关系。在所有参与者中，中风后CC两个区域的FA均显著降低（<0.001），并与运动功能水平呈显著正相关。然而，这些关系因运动障碍程度而异：在运动障碍相对较轻的个体（Fugl-Meyer运动评分>39）中，运动状态与CC中的FA相关，而与CST中的FA无关；而在运动障碍相对较重的个体（Fugl-Meyer运动评分≤39）中，运动状态与CST中的FA相关，而与CC中的FA无关。中风后半球间运动连接在运动功能中的作用可能因运动障碍水平而异。这些发现强调了中风的异质性，并表明针对不同亚组的生物标志物和治疗方法可能是必要的。
