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.
Structural neuroimaging studies on chronic smokers using voxel-based morphometry (VBM) had provided cumulative evidence of gray matter (GM) changes relative to nonsmokers. However, not all the studies reported entirely consistent findings. Here, we aimed at identifying consistent GM anomalies in chronic smokers by performing a meta-analysis, and a systematic search of VBM studies on chronic smokers and nonsmokers published in PubMed and Embase database from 2000 to April 2012. Meta-analysis was performed using a newly improved voxel-based meta-analytic tool, namely effect size signed differential mapping, to quantitatively explore the GM abnormalities between chronic smokers and nonsmokers. A total of 7 eligible VBM studies involving 213 chronic smokers and 205 nonsmokers met the inclusion criteria. A considerable regional GM volume decrease was detected in the anterior cingulate cortex (ACC) (BA 24) extending to BA32 in chronic smokers. The findings remain largely unchanged in the entire brain jackknife sensitivity analyses. The results of the present meta-analysis provide evidence of GM changes in ACC in chronic smokers which may be an important potential therapeutic neuro-target for nicotine dependence.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.