J Psychiatry Neurosci 2013; 38(1):43-48
Ke Xu, MD, PhD;* Wenyan Jiang, MD;* Ling Ren, MD; Xuan Ouyang, MD; Yifeng Jiang, PhD; Feng Wu, MD, PhD; Lingtao Kong, MD; Fay Womer, MD; Zhening Liu, MD; Hilary P. Blumberg, MD; Yanqing Tang, MD, PhD; Fei Wang, MD, PhD
W. Jiang, Wu, Kong, Tang — Department of Psychiatry, The First Affiliated Hospital, China Medical University, Shenyang, China; Xu, Ren, Wang — Department of Radiology, The First Affiliated Hospital, China Medical University, Shenyang, China; Ouyang, Liu — The Institute of Mental Health, Second Xiangya Hospital of Central South University, Changsha, China; Y. Jiang, Blumberg — Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Conn.; Womer, Blumberg, Wang — Department of Psychiatry, Yale University School of Medicine, New Haven, Conn.
Background: Abnormalities in the anterior interhemispheric connections provided by the corpus callosum (CC) have long been implicated in major depressive disorder (MDD). The purpose of this study was to investigate interhemispheric connectivity in medication-naive patients with MDD by measuring fractional anisotropy in the CC with diffusion tensor imaging (DTI) techniques.
Methods: We obtained DTI scans from medication-naive patients with MDD and from matched healthy controls. Fractional anisotropy values were compared using semiautomatic region of interest methods to localize the regional CC differences between these 2 groups.
Results: We enrolled 27 patients and 27 controls in our study. Fractional anisotropy values were significantly lower in the anterior genu of the CC in the MDD group than in the control group (p = 0.009, corrected); results were not significantly different in any other CC subregions.
Limitations: As patients with MDD were already experiencing acute episodes, future studies of individuals at risk for MDD are warranted to elucidate the interhemispheric connectivity abnormalities associated with the predisposition to MDD.
Conclusion: The findings demonstrate abnormalities in the structural integrity of the anterior genu of the CC in medication-naive individuals with MDD, which may contribute to impairment of interhemispheric connectivity in patients with this disorder.
Submitted Sept. 20, 2011; Revised Jan. 16, Feb. 14, 2012; Accepted Feb. 16, 2012.
Acknowledgements: Funding for this study was provided by the National Natural Science Foundation of China (81071099 to Y. Tang and 81101012 to F. Wu), the Liaoning Science and Technology Foundation (2008225010-14 to Y. Tang), the Liaoning Doctor Scientific Foundation (20111099 to F. Wu), National Institution of Health (K01MH086621 to F. Wang), the National Alliance for Research on Schizophrenia and Depression (F. Wang) and the Klingenstein Foundation (F. Wang).
Competing interests: As above for Y. Tang, F. Wu and F. Wang. None declared for other authors.
Contributors: K. Xu, F. Wu, H. Blumberg, Y. Tang and F. Wang designed the study. W. Jiang, L. Ren and L. Kong accquired data. X. Ouyang, Y. Jiang, F. Womer and Z. Liu analyzed the data. X. Ouyang, H. Blumberg, Y. Tang and F. Wang wrote the article. All authors reviewed the article and provided approval for publication.
Correspondence to: Y. Tang, Department of Psychiatry, The First Affiliated Hospital, China Medical University, 155 Nanjing North Street, Shenyang 110001, Liaoning, China; firstname.lastname@example.org; and F. Wang, Department of Psychiatry, Yale University School of Medicine, New Haven CT 06511, USA; email@example.com