Structural and diffusion property alterations in unaffected siblings of patients with obsessive-compulsive disorder.
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.
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.
Ziwen
Z
Peng
Department of Radiology and BRIC, University of North Carolina at Chapel Hill, North Carolina, United States of America.
Feng
F
Shi
Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.
Changzheng
C
Shi
Guangzhou Psychiatry Hospital, Guangzhou, China.
Guodong
G
Miao
Guangzhou Psychiatry Hospital, Guangzhou, China.
Qiong
Q
Yang
Department of Radiology and BRIC, University of North Carolina at Chapel Hill, North Carolina, United States of America.
Wei
W
Gao
Carolina Institute for Developmental Disabilities and the Department of Psychiatry, University of North Carolina at Chapel Hill, North Carolina, United States of America.
Jason J
JJ
Wolff
Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
Raymond C K
RC
Chan
Department of Radiology and BRIC, University of North Carolina at Chapel Hill, North Carolina, United States of America ; Department of Brain and Cognitive Engineering, Korea University, Korea.
Dinggang
D
Shen
D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000473:pathology*; D010296:Parietal Lobe / Q000473:pathology; D035781:Siblings; D055815:Young Adult