Background With the increasing efforts to a better understanding of psychiatric diseases, detection of brain morphological alterations is necessary. This study compared two methods—voxel-based morphometry (VBM) and region of interest (ROI) analyses—to identify significant gray matter changes of patients with bipolar disorder type I (BP I). Results The VBM findings suggested gray matter reductions in the left precentral gyrus and right precuneus of the patients compared to healthy subjects (α = 0.0005, uncorrected). However, no regions reached the level of significance in ROI analysis using the three atlases, i.e., hammers, lpba40, and neuromorphometrics atlases (α = 0.0005). Conclusion It can be concluded that VBM analysis seems to be more sensitive to partial changes in this study. If ROI analysis is employed in studies to detect structural brain alterations between groups, it is highly recommended to use VBM analysis besides.

Background: With the increasing efforts to a better understanding of psychiatric diseases, detection of brain morphological alterations are necessary. This study compared two methods-voxel based morphometry (VBM) and region of interest (ROI) analyses- to identify significant gray matter changes of patients with bipolar disorder type I (BP I). Methods: The structural MRI were obtained in a total of 50 subjects (25 healthy subjects with a mean age of 34.48±8.32 years as a control group and 25 patients with a mean age of 37.68±10.88 years). We compared the gray matter alteration results obtained by VBM analysis using the DARTEL approach with those obtained using ROI analysis which applies three probabilistic brain atlases namely, hammers, lpba40, and neuromorphometrics atlases. All analyses were conducted via the Computational Anatomy Toolbox (CAT12) implemented in Statistical Parametric Mapping (SPM12) software package. Results: The VBM findings suggested that gray matter reductions in left precentral and right precuneus of the patients compared to healthy subjects(α=0.0005, uncorrected). However, No regions reached the level of significance in ROI analysis using the three atlases (α=0.0005). Conclusion: It can be concluded that VBM analysis seems to be more sensitive to partial changes in this study. If ROI analysis is employed in studies to detect structural brain alterations between groups, it is highly recommended to use VBM analysis besides. Keywords: Voxel-Based Morphometry; ROI Analysis; bipolar disorder; MRI; brain.