Past Issues

Background:Major depressive disorder (MDD) is one of the prevalent and disabling psychiatric disorders. MDD is a complex disorder with marked heterogeneity in pathophysiology, diagnosis, and treatment. Currently, neuroimaging has given new insights into the structure and function of the brain in individuals with major depression. Results:We did a Medline search with key words “major depressive disorder” combined with “neuroimaging” or “brain imaging” up to May 15, 2008. We reviewed all identifi ed published articles. Results: The most consistent fi ndings in the pathophysiology studies of MDD with neuroimaging are abnormalities in the anterior regions of the brain, especially frontal, limbic, and cingulate regions, which presenting with increased rate of white matter hyperintensities, defect of white matter integrity, reduced glial cell density, reductions in cerebral fl ow or glucose metabolism. Thus, MDD is a brain disorder proved by neuroimaging and other biological fi ndings. Findings of the regional abnormalities by neuroimaging may have clinical utility in both diagnosis and treatment of depression. Neuroimaging in geriatric depression found more subcortical ischemic vascular lesion, which is called vascular depression. It is noteworthy that the involved regions of brain and the neural processing of facial expressions may differ between MDD and bipolar disorder. Interestingly, there are clear regional change pattern differences across unique treatments, including medication and cognitive behavior therapy, affecting similar region but in different ways. Conclusion: We conclude that the fi ndings of neuroimaging in individuals with MDD can help clinicians to get comprehensive understanding of depression in pathophysiology, diagnosis and treatment, and to ensure the quality of care in depression.