Disrupted white matter (WM) integrity in the anterior thalamic radiation (ATR) has been identified in individuals with bipolar disorder (BD). We explored whether structural WM aberration in the ATR could be visually evaluated by diffusion tensor tractography (DTT). The study comprised 114 participants, including 57 patients with BD and 57 healthy controls (HCs). A poorly visualized ATR reflects an abnormal WM structure. We defined a poorly visualized ATR as one in which at least one ATR fiber bundle failed to reach to the boundary between gray and white matter. Poor ATR visualization occurred significantly more frequently in the left ATR of those with BD than in HCs (P = 0.042). Furthermore, we adjusted the fractional anisotropy (FA) value and when evaluation of a given ATR changed from good to poor, we defined that value as the optimal FA threshold. In the right ATR, we successfully classified BD and HCs with 71.1% accuracy (sensitivity = 89.5% and specificity = 52.6%) and an area under the curve of 0.76 using the optimal FA threshold of 0.28. The present results suggest that the optimal FA threshold can serve as a biological marker that distinguishes individuals with BD from HCs. Thus, visual evaluation of the ATR by DTT may prove to be a useful adjunctive diagnostic tool for BD in clinical practice.

Background and objectiveMany surveys of neural integrity of the cerebral white matter with psychiatric diseases on diffusion tensor imaging have recently been performed, but these mainly utilize fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) values, and the results were inconsistent and not fully applied clinically. In this study, we investigated the possibility of differentiating between Alzheimer’s disease (AD) and elderly major depressive disorder (MDD) patients in whom early-stage symptoms are difficult to diagnose, by visually evaluating cerebral nerve fascicles utilizing diffusion tensor tractography. We also measured and evaluated FA and ADC values at the same time.Subjects and methodsThe subjects included 13 AD patients (age: 69.5 ± 5.1 years), 19 MDD patients (65.8 ± 5.7 years), and 22 healthy control (HC) subjects (67.4 ± 4.8 years). Images were acquired using a 1.5T magnetic resonance imaging device and analyzed by diffusion tensor tractography analysis software.ResultsDepiction of the anterior thalamic radiation (ATR) tended to be poor in AD patients unlike in MDD patients and HC subjects. The FA values in the left superior longitudinal fasciculus and fornix (FX) in AD patients were significantly different from those in MDD patients and HC subjects. The ADC values in the bilateral ATR and left superior and inferior longitudinal fasciculi, left inferior fronto-occipital fasciculus, and FX in AD patients were significantly different from those in MDD patients and HC subjects.ConclusionVisual evaluation of the ATR in combination with the FA values of the left superior longitudinal fasciculus and FX and ADC values of the bilateral ATR, left superior and inferior longitudinal fasciculi, left inferior fronto-occipital fasciculus, and FX is useful for differentiating between AD and MDD patients, which further suggests that it may become a useful auxiliary diagnostic tool.

ObjectiveWe objectively evaluated the presence or absence of atrophy of the subgenual anterior cingulate cortex (sgACC) and the subcallosal anterior cingulate cortex (scACC), using new voxel-based morphometry (VBM) software employing Statistical Parametric Mapping software v8 and diffeomorphic anatomic registration through an exponentiated lie algebra. We prepared a database covering young-mature adulthood and investigated the clinical usefulness of the evaluation.Subjects and methodsOne hundred seven patients with major depressive disorder (MDD), 74 patients with bipolar disorder (BD), and 240 healthy control subjects underwent 1.5T magnetic resonance imaging scanning. Using new VBM software and databases covering young-mature adults and the elderly, target volumes of interest were set in the sgACC and scACC, four indicators (severity, extent, ratio, and whole-brain extent) were determined, and the presence or absence of atrophy of the sgACC and scACC was evaluated on the basis of the indicators. In addition, the relationships between the presence or absence of atrophy of the sgACC and scACC and performance of diagnosing MDD and BD and therapeutic drugs were investigated.ResultsIt was clarified that the disease is likely to be MDD when atrophy is detected in the sgACC, and likely to be BD when no atrophy is detected in the sgACC but is detected in the scACC. Regarding the relationship with therapeutic drugs, it was clarified that, when atrophy is detected in both the sgACC and the scACC, concomitant administration of mood stabilizers and atypical antipsychotics acting as dopamine-system stabilizers is necessary in many cases.ConclusionVBM on magnetic resonance imaging enabled automatic analysis of atrophy in the sgACC and scACC, and findings obtained by this procedure are useful not only for differentiation of MDD and BD patients but also for selection of prescriptions.

Objectives The present study investigated the usefulness of evaluating the existence of volume reduction in brain regions using voxel‐based morphometry (VBM) to dissociate major depressive disorder (MDD) from bipolar disorder (BD). Methods/Design This study enrolled 92 individuals with MDD, 32 individuals with BD, and 43 healthy controls (HCs). We focused on gray matter volume (GMV) of the subgenual anterior cingulate cortex (sgACC), subcallosal area (SCA), and hippocampus. The degree of volume reduction in these brain regions was calculated as the z score, and the differences of z scores in these regions were investigated among the MDD, BD, and HC groups. We then performed a receiver operating characteristic curve analysis to dissociate the individuals with MDD and BD from the HCs based on the z scores in the GMV of these brain regions. Results While there were no significant differences in the z scores of the hippocampus among the three groups, the z score of the sgACC was significantly higher in the MDD group than in the BD and HC groups, and the SCA z score was significantly higher in the MDD and BD groups than in the HC group. Conclusions Our findings suggest that VBM evaluation of GMV reduction in the sgACC may be useful as an objective adjunctive tool to distinguish between MDD and BD.

BackgroundDespite being a very common psychiatric disorder, physicians often have difficulty making a diagnosis of major depressive disorder (MDD) because, without established diagnostic criteria, they have to depend on interviews with patients and observation to assess psychiatric symptoms. However, previous researchers have reported that magnetic resonance imaging (MRI) scans identify morphological changes in the brains of patients with MDD, which inspired us to hypothesize that assessment of local changes in the brain using voxel-based morphometry would serve as an auxiliary diagnostic method for MDD. Therefore, we focused on the VSRAD® plus (voxel-based specific regional analysis system for Alzheimer’s disease), a diagnostic support system for use in early Alzheimer’s disease, which allowed us to identify regional atrophy in the brain easily based on images obtained from MRI scans.MethodsThe subjects were 75 patients with MDD, 15 with bipolar disorder, and 30 healthy subjects, aged 54–82 years. First, 1.5 T MRI equipment was used to scan three-dimensional T1-weighted images for the individual subjects, and the imaged data were analyzed by VSRAD advance (voxel-based morphometric software developed for diagnosis of early Alzheimer’s disease). The efficacy of the equipment for diagnosis of MDD was evaluated based on the distribution of atrophy in the subgenual anterior cingulate cortex (sACC) on the z-score map obtained.ResultsNo significant difference in atrophy was noted between the left and right sACCs. The VSRAD advance used in the present study was more effective than the VSRAD plus for diagnosis of MDD, with a sensitivity of 90.7%, specificity of 86.7%, accuracy of 89.5%, a positive predictive value of 94.4%, and a negative predictive value of 78.8%. In particular, atrophy was observed in the subcallosal area of the sACC.ConclusionThe identification of atrophy in the sACC, in particular of the subcallosal area, with the use of updated voxel-based morphometric software proved to be effective as an auxiliary diagnostic method for MDD.