Lima Santos João Paulo, Versace Amelia, Arora Manan, Bertocci Michele A, Chase Henry W, Skeba Alex, Graur Simona, Bonar Lisa, Maffei Chiara, Yendiki Anastasia, Rasmussen Steven A, Haber Suzanne N, Phillips Mary L
Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA.
Magnetic Resonance Research Center, University of Pittsburgh, Pittsburgh, PA, USA.
Transl Psychiatry. 2024 Oct 2;14(1):410. doi: 10.1038/s41398-024-03101-9.
Obsessive-compulsive disorder is a psychiatric disorder characterized by intrusive thoughts and repetitive behaviors. There are two prominent features: Harm Avoidance (HA) and Incompleteness (INC). Previous resting-state studies reported abnormally elevated connectivity between prefrontal cortical (PFC) and subcortical regions (thalamus, striatum) in OCD participants. Yet, little is known about the white matter (WM) structural abnormalities in these connections. Using brain parcellation and segmentation, whole brain tractography, and Neurite Orientation Dispersion and Density Imaging (NODDI), we aimed to characterize WM structural abnormalities in OCD vs. healthy controls and determine the extent to which NODDI indices of these connections were associated with subthreshold-threshold HA, INC and overall OCD symptom severity across all participants. Four PFC regions were segmented: ventral medial (vmPFC), ventrolateral (vlPFC), dorsomedial (dmPFC), and dorsolateral (dlPFC). NODDI Neurite Density (NDI) and Orientation Dispersion (ODI) indices of WM structure were extracted from connections between these PFC regions and the thalamus (42 OCD, 44 healthy controls, mean age[SD] = 23.65[4.25]y, 63.9% female) and striatum (38 OCD, 41 healthy controls, mean age[SD] = 23.59[4.27]y, 64.5% female). Multivariate analyses of covariance revealed no between-group differences in these indices. Multivariate regression models revealed that greater NDI in vmPFC-thalamus, greater NDI and ODI in vmPFC-striatum, and greater NDI in dmPFC-thalamus connections were associated with greater INC severity (Q ≤ 0.032). These findings highlight the utility of NODDI in the examination of WM structure in OCD, provide valuable insights into specific WM alterations underlying dimensional INC, and can facilitate the development of customized treatments for OCD individuals with treatment-resistant symptoms.
强迫症是一种以侵入性思维和重复行为为特征的精神障碍。它有两个突出特征：回避伤害（HA）和不完整性（INC）。先前的静息态研究报告称，强迫症患者前额叶皮质（PFC）与皮质下区域（丘脑、纹状体）之间的连接性异常升高。然而，对于这些连接中的白质（WM）结构异常知之甚少。我们使用脑图谱分割、全脑纤维束成像以及神经突方向离散度与密度成像（NODDI），旨在描述强迫症患者与健康对照者的WM结构异常，并确定这些连接的NODDI指数与所有参与者的阈下-阈上HA、INC以及总体强迫症症状严重程度之间的关联程度。我们分割了四个PFC区域：腹内侧（vmPFC）、腹外侧（vlPFC）、背内侧（dmPFC）和背外侧（dlPFC）。从这些PFC区域与丘脑（42名强迫症患者，44名健康对照者，平均年龄[标准差]=23.65[4.25]岁，63.9%为女性）以及纹状体（38名强迫症患者，41名健康对照者，平均年龄[标准差]=23.59[4.27]岁，64.5%为女性）之间的连接中提取WM结构的NODDI神经突密度（NDI）和方向离散度（ODI）指数。多变量协方差分析显示这些指数在组间无差异。多变量回归模型显示，vmPFC-丘脑之间更高的NDI、vmPFC-纹状体之间更高的NDI和ODI以及dmPFC-丘脑连接中更高的NDI与更严重的INC相关（Q≤0.032）。这些发现突出了NODDI在检查强迫症WM结构方面的效用，为维度INC背后的特定WM改变提供了有价值的见解，并有助于为有治疗抵抗症状的强迫症个体开发定制治疗方法。
