Identification of bipolar disorder using a combination of multimodality magnetic resonance imaging and machine learning techniques
Background Bipolar disorder (BPD) is a common mood disorder that is often goes misdiagnosed or undiagnosed. Recently, machine learning techniques have been combined with neuroimaging methods to aid in the diagnosis of BPD. However, most studies have focused on the construction of classifiers based on single-modality MRI. Hence, in this study, we aimed to construct a support vector machine (SVM) model using a combination of structural and functional MRI, which could be used to accurately
... accurately identify patients with BPD. Methods In total, 44 patients with BPD and 36 healthy controls were enrolled in the study. Clinical evaluation and MRI scans were performed for each subject. Next, image pre-processing, voxel-based morphometry (VBM), and ReHo analyses were performed. The grey matter volumes or ReHo values of the clusters showed significant differences as discriminant features in the SVM classification model. Based on extracted features, the SVM model was established, and discriminant analysis was performed. Results After using the two-sample t-test with multiple comparisons, 12 clusters with significant differences were extracted from the data. Next, we used both VBM and ReHo data to construct the new SVM classifier, which could effectively identify patients with BPD at an accuracy of 90% in the test data (p=0.0014). Limitations The sample size was small, and we were unable to eliminate the potential effects of medications. Conclusions A combination of structural and functional MRI can be of added value in the construction of SVM classifiers to aid in the accurate identification of BPD in the clinic.