Etherton Mark R, Wu Ona, Cougo Pedro, Giese Anne-Katrin, Cloonan Lisa, Fitzpatrick Kaitlin M, Kanakis Allison S, Boulouis Gregoire, Karadeli Hasan H, Lauer Arne, Rosand Jonathan, Furie Karen L, Rost Natalia S
From the J. Philip Kistler Stroke Research Center (M.R.E., O.W., P.C., A.-K.G., L.C., K.M.F., A.S.K., G.B., H.H.K., A.L., N.S.R.), Department of Neurology, and Athinoula A. Martinos Center for Biomedical Imaging (O.W.), Department of Radiology, Massachusetts General Hospital and Harvard Medical School; Division of Neurocritical Care and Emergency Neurology (J.R.), Department of Neurology and Center for Human Genetic Research, Massachusetts General Hospital, Boston; and Department of Neurology (K.L.F.), Rhode Island Hospital, Alpert Medical School of Brown University, Providence.
Neurology. 2017 May 2;88(18):1701-1708. doi: 10.1212/WNL.0000000000003890. Epub 2017 Apr 5.
To characterize the effect of white matter microstructural integrity on cerebral tissue and long-term functional outcomes after acute ischemic stroke (AIS).
Consecutive AIS patients with brain MRI acquired within 48 hours of symptom onset and 90-day modified Rankin Scale (mRS) score were included. Acute infarct volume on diffusion-weighted imaging (DWIv) and white matter hyperintensity volume (WMHv) on T2 fluid-attenuated inversion recovery MRI were measured. Median fractional anisotropy (FA), mean diffusivity, radial diffusivity, and axial diffusivity values were calculated within normal-appearing white matter (NAWM) in the hemisphere contralateral to the acute lesion. Regression models were used to assess the association between diffusivity metrics and acute cerebral tissue and long-term functional outcomes in AIS. Level of significance was set at < 0.05 for all analyses.
Among 305 AIS patients with DWIv and mRS score, mean age was 64.4 ± 15.9 years, and 183 participants (60%) were male. Median NIH Stroke Scale (NIHSS) score was 3 (interquartile range [IQR] 1-8), and median normalized WMHv was 6.19 cm (IQR 3.0-12.6 cm). Admission stroke severity (β = 0.16, < 0.0001) and small vessel stroke subtype (β = -1.53, < 0.0001), but not diffusivity metrics, were independently associated with DWIv. However, median FA in contralesional NAWM was independently associated with mRS score (β = -9.74, = 0.02), along with age, female sex, NIHSS score, and DWIv.
FA decrease in NAWM contralateral to the acute infarct is associated with worse mRS category at 90 days after stroke. These data suggest that white matter integrity may contribute to functional recovery after stroke.
探讨急性缺血性卒中（AIS）后白质微观结构完整性对脑组织及长期功能预后的影响。
纳入症状发作48小时内接受脑部MRI检查且有90天改良Rankin量表（mRS）评分的连续性AIS患者。测量扩散加权成像（DWIv）上的急性梗死体积以及T2液体衰减反转恢复MRI上的白质高信号体积（WMHv）。计算急性病变对侧半球正常外观白质（NAWM）内的中位数各向异性分数（FA）、平均扩散率、径向扩散率和轴向扩散率值。采用回归模型评估扩散率指标与AIS患者急性脑组织及长期功能预后之间的关联。所有分析的显著性水平设定为<0.05。
在305例有DWIv和mRS评分的AIS患者中，平均年龄为64.4±15.9岁，183名参与者（60%）为男性。中位数美国国立卫生研究院卒中量表（NIHSS）评分为3（四分位间距[IQR]1 - 8），中位数标准化WMHv为6.19 cm（IQR 3.0 - 12.6 cm）。入院时卒中严重程度（β = 0.16，<0.0001）和小血管卒中亚型（β = -1.53，<0.0001）而非扩散率指标与DWIv独立相关。然而，对侧NAWM的中位数FA与mRS评分独立相关（β = -9.74，= 0.02），同时还与年龄、女性性别、NIHSS评分和DWIv相关。
急性梗死对侧NAWM中FA降低与卒中后90天较差的mRS分级相关。这些数据表明白质完整性可能有助于卒中后的功能恢复。
