From the Department of Radiology (A.K., A.R.), Brain and Mind Research Institute (A.K., H.K., B.B.N., A.R., C.I.), and Department of Neurology (H.K., B.B.N., C.I.), Weill Cornell Medical College, New York, NY.
Stroke. 2014 Mar;45(3):717-22. doi: 10.1161/STROKEAHA.113.003645. Epub 2014 Feb 12.
The Network Modification (NeMo) Tool uses a library of brain connectivity maps from normal subjects to quantify the amount of structural connectivity loss caused by focal brain lesions. We hypothesized that the Network Modification Tool could predict remote brain tissue loss caused by poststroke loss of connectivity.
Baseline and follow-up MRIs (10.7±7.5 months apart) from 26 patients with acute ischemic stroke (age, 74.6±14.1 years, initial National Institutes of Health Stroke Scale, 3.1±3.1) were collected. Lesion masks derived from diffusion-weighted images were superimposed on the Network Modification Tool's connectivity maps, and regional structural connectivity losses were estimated via the Change in Connectivity (ChaCo) score (ie, the percentage of tracks connecting to a given region that pass through the lesion mask). ChaCo scores were correlated with subsequent atrophy.
Stroke lesions' size and location varied, but they were more frequent in the left hemisphere. ChaCo scores, generally higher in regions near stroke lesions, reflected this lateralization and heterogeneity. ChaCo scores were highest in the postcentral and precentral gyri, insula, middle cingulate, thalami, putamen, caudate nuclei, and pallidum. Moderate, significant partial correlations were found between baseline ChaCo scores and measures of subsequent tissue loss (r=0.43, P=4.6×10(-9); r=0.61, P=1.4×10(-18)), correcting for the time between scans.
ChaCo scores varied, but the most affected regions included those with sensorimotor, perception, learning, and memory functions. Correlations between baseline ChaCo and subsequent tissue loss suggest that the Network Modification Tool could be used to identify regions most susceptible to remote degeneration from acute infarcts.
网络修饰（NeMo）工具使用来自正常受试者的大脑连接图库来量化由局灶性脑损伤引起的结构连接损失量。我们假设网络修饰工具可以预测由中风后连接丧失引起的远程脑组织损失。
从 26 例急性缺血性中风患者（年龄 74.6±14.1 岁，初始国立卫生研究院中风量表 3.1±3.1）中收集基线和随访 MRI（间隔 10.7±7.5 个月）。从弥散加权图像中获得的病变掩模叠加在网络修饰工具的连接图上，通过连通性变化（ChaCo）评分（即，连接到给定区域的轨道中有多少百分比穿过病变掩模）来估计区域结构连接损失。ChaCo 评分与随后的萎缩相关。
中风病变的大小和位置各不相同，但在左半球更为常见。ChaCo 评分通常在靠近中风病变的区域较高，反映了这种偏侧性和异质性。ChaCo 评分在中央后回和中央前回、岛叶、中扣带回、丘脑、壳核、尾状核和苍白球最高。基线 ChaCo 评分与随后组织损失的测量值之间存在中度、显著的部分相关（r=0.43，P=4.6×10(-9)；r=0.61，P=1.4×10(-18)），校正了扫描之间的时间。
ChaCo 评分各不相同，但受影响最严重的区域包括那些具有感觉运动、感知、学习和记忆功能的区域。基线 ChaCo 与随后组织损失之间的相关性表明，网络修饰工具可用于识别最易受急性梗死引起的远程变性影响的区域。
