Department of Neurology, The Second Hospital of Dalian Medical University, Dalian, China.
Department of Orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, China.
Magn Reson Imaging. 2024 Dec;114:110234. doi: 10.1016/j.mri.2024.110234. Epub 2024 Sep 15.
This study aimed to assess changes in white matter microstructure among patients undergoing obstructive sleep apnea hypopnea syndrome (OSAHS) complicated by cognitive impairment through neurite orientation dispersion and density imaging (NODDI), and evaluate the relationship to cognitive impairment as well as the diagnostic performance in early intervention.
Totally 23 OSAHS patients, 43 OSAHS patients complicated by cognitive impairment, and 15 healthy controls were enrolled in OSA, OSACI and HC groups of this work. NODDI toolbox and FMRIB's Software Library (FSL) were used to calculate neurite density index (NDI), Fractional anisotropy (FA), volume fraction of isotropic water molecules (Viso), and orientation dispersion index (ODI). Tract-based spatial statistics (TBSS) were carried out to examine the above metrics with one-way ANOVA. This study explored the correlations of the above metrics with mini-mental state examination (MMSE), and montreal cognitive assessment (MoCA) scores. Furthermore, receiver operating characteristic (ROC) curves were plotted. Meanwhile, area under curve (AUC) values were calculated to evaluate the diagnostic performance of the above metrics.
NDI, ODI, Viso, and FA were significantly different among different brain white matter regions, among which, difference in NDI showed the greatest statistical significance. In comparison with HC group, OSA group had reduced NDI and ODI, whereas elevated Viso levels. Conversely, compared to the OSA group, the OSACI group displayed a slight increase in NDI and ODI values, which remained lower than HC group, viso values continued to rise. Post-hoc analysis highlighted significant differences in these metrics, except for FA, which showed no notable changes or correlations with neuropsychological tests. ROC analysis confirmed the diagnostic efficacy of NDI, ODI, and Viso with AUCs of 0.6908, 0.6626, and 0.6363, respectively, whereas FA's AUC of 0.5042, indicating insufficient diagnostic efficacy.
This study confirmed that NODDI effectively reveals microstructural changes in white matter of OSAHS patients with cognitive impairment, providing neuroimaging evidence for early clinical diagnosis and intervention.
本研究旨在通过神经纤维各向异性分布和密度成像（NODDI）评估阻塞性睡眠呼吸暂停低通气综合征（OSAHS）合并认知障碍患者的脑白质微观结构变化，并评估与认知障碍的关系以及早期干预的诊断性能。
本研究共纳入 23 例 OSAHS 患者、43 例 OSAHS 合并认知障碍患者和 15 例健康对照者，分别纳入 OSA、OSACI 和 HC 组。采用 NODDI 工具箱和 FMRIB 的软件库（FSL）计算神经纤维密度指数（NDI）、各向异性分数（FA）、各向同性水分子体积分数（Viso）和方向分散指数（ODI）。采用基于体素的空间统计学（TBSS）进行单因素方差分析。探讨上述指标与简易精神状态检查（MMSE）和蒙特利尔认知评估（MoCA）评分的相关性。绘制受试者工作特征（ROC）曲线，并计算曲线下面积（AUC）值评估上述指标的诊断性能。
不同脑白质区域之间的 NDI、ODI、Viso 和 FA 存在显著差异，其中 NDI 的差异具有最大的统计学意义。与 HC 组相比，OSA 组的 NDI 和 ODI 降低，Viso 升高。相反，与 OSA 组相比，OSACI 组的 NDI 和 ODI 值略有升高，但仍低于 HC 组，Viso 值继续升高。事后分析显示这些指标有显著差异，除 FA 外，FA 无明显变化，与神经心理学测试也无相关性。ROC 分析证实 NDI、ODI 和 Viso 的诊断效能良好，AUC 分别为 0.6908、0.6626 和 0.6363，而 FA 的 AUC 为 0.5042，表明诊断效能不足。
本研究证实 NODDI 可有效揭示 OSAHS 合并认知障碍患者脑白质的微观结构变化，为早期临床诊断和干预提供神经影像学证据。
