Gray Matter Atrophy in Behavioral Variant Frontotemporal Dementia: A Meta-Analysis of Voxel-Based Morphometry Studies

Background: Structural neuroimaging studies on behavioral variant frontotemporal dementia (bvFTD) using the voxel-based morphometry (VBM) method reported not entirely consistent findings. Methods: A systematic review of VBM studies of bvFTD patients and healthy controls (HC) published in PubMed and Embase databases from 2000 to June 2011 was conducted. Meta-analysis was performed using a newly improved voxel-based meta-analytic tool, namely, effect size signed differential mapping, to quantitatively explore the gray matter (GM) changes between bvFTD patients and HC subjects. Results: 11 VBM studies involving 237 bvFTD patients and 297 HC subjects met the inclusion criteria. Considerable regional GM volume decrease was detected in the anterior medial frontal cortex (BA 9), extending to other frontal areas (BA 8, 10, 46, 24, 32), and other brain areas, such as the insula cortex, as well as the subcortical striatal regions in patients with bvFTD compared with HC subjects. The findings of the present study remain largely unchanged in the entire brain jackknife sensitivity analyses. Conclusions: The present meta-analysis provides evidence of GM changes in the frontal-striatal-limbic brain areas in patients with bvFTD. Furthermore, GM atrophy in the fron-toinsular cortex and anterior cingulate cortex may be important anatomical changes for the diagnosis of patients with bvFTD.