Peng Ziwen, Shi Feng, Shi Changzheng, Miao Guodong, Yang Qiong, Gao Wei, Wolff Jason J, Chan Raymond C K, Shen Dinggang
Department of Radiology and BRIC, University of North Carolina at Chapel Hill, North Carolina, United States of America ; Department of Psychology, South China Normal University, Guangzhou, China.
Department of Radiology and BRIC, University of North Carolina at Chapel Hill, North Carolina, United States of America.
PLoS One. 2014 Jan 28;9(1):e85663. doi: 10.1371/journal.pone.0085663. eCollection 2014.
Disrupted white matter integrity and abnormal cortical thickness are widely reported in the pathophysiology of obsessive-compulsive disorder (OCD). However, the relationship between alterations in white matter connectivity and cortical thickness in OCD is unclear. In addition, the heritability of this relationship is poorly understood. To investigate the relationship of white matter microstructure with cortical thickness, we measure fractional anisotropy (FA) of white matter in 30 OCD patients, 19 unaffected siblings and 30 matched healthy controls. Then, we take those regions of significantly altered FA in OCD patients compared with healthy controls to perform fiber tracking. Next, we calculate the fiber quantity in the same tracts. Lastly, we compare cortical thickness in the target regions of those tracts. Patients with OCD exhibited decreased FA in cingulum, arcuate fibers near the superior parietal lobule, inferior longitudinal fasciculus near the right superior temporal gyrus and uncinate fasciculus. Siblings showed reduced FA in arcuate fibers near the superior parietal lobule and anterior limb of internal capsule. Significant reductions in both fiber quantities and cortical thickness in OCD patients and their unaffected siblings were also observed in the projected brain areas when using the arcuate fibers near the left superior parietal lobule as the starting points. Reduced FA in the left superior parietal lobule was observed not only in patients with OCD but also in their unaffected siblings. Originated from the superior parietal lobule, the number of fibers was also found to be decreased and the corresponding cortical regions were thinner relative to controls. The linkage between disrupted white matter integrity and the abnormal cortical thickness may be a vulnerability marker for OCD.
在强迫症（OCD）的病理生理学中，广泛报道了白质完整性破坏和皮质厚度异常。然而，OCD中白质连接性改变与皮质厚度之间的关系尚不清楚。此外，这种关系的遗传性也知之甚少。为了研究白质微观结构与皮质厚度的关系，我们测量了30名OCD患者、19名未受影响的同胞和30名匹配的健康对照者白质的分数各向异性（FA）。然后，我们选取OCD患者与健康对照相比FA有显著改变的区域进行纤维追踪。接下来，我们计算相同束中的纤维数量。最后，我们比较这些束的目标区域的皮质厚度。OCD患者在扣带、顶上小叶附近的弓状纤维、右侧颞上回附近的下纵束和钩束中FA降低。同胞在顶上小叶附近的弓状纤维和内囊前肢中FA降低。当以左侧顶上小叶附近的弓状纤维为起点时，在OCD患者及其未受影响的同胞的投射脑区中也观察到纤维数量和皮质厚度均显著降低。不仅在OCD患者中，而且在他们未受影响的同胞中也观察到左侧顶上小叶FA降低。起源于顶上小叶的纤维数量也减少，并且相应的皮质区域相对于对照更薄。白质完整性破坏与皮质厚度异常之间的联系可能是OCD的一个易感性标志物。
