[Structural changes of brain gray matter in male long-term smokers under magnetic resonance imaging]

Objective: To evaluate gray matter structure changes in long-term male smokers by voxel-based morphological method. Methods: Fifty long-term smokers and 37 non-smoking healthy volunteers were scanned with Siemens Skyro 3.0T magnetic resonance scanner from August 2014 to August 2016. The subjects underwent routine MRI (excluding intracranial lesions) sequences and 3D-T1 structural sequences (3D-mprage). SPM8 pretreatment based on Matlab was used to analyze the structural data. All of the data were analyzed by SPM8 software. The data were compared between groups with independent sample t test. Spearman correlation analysis was used to analyze the relationship between gray matter volume (GMV) and smoking data of two groups. Results: The gray matter volume of bilateral thalamic, right supramarginal gyrus, left supramarginal gyrus and left putamen of smoking group were (0.55±0.07), (0.40±0.05), (0.48±0.07) and (0.14±0.04) voxels, respectively, and the gray matter volume of the corresponding gyri in control group were (0.61±0.09), (0.43±0.06), (0.54±0.07) and (0.16±0.03) voxels, respectively; and the gray matter volume of smoking group were all lower than those in control group (t=-3.81, -3.51, -3.86, -2.33, all P<0.05), family wise error (FWE) correction (P<0.05). The gray matter volume of bilateral thalamus, right supramarginal gyrus and left putamen was negatively correlated with smoking index (r=-0.368, -0.189, -0.274, all P<0.05), and also negatively correlated with smoking years (r=-0.391, -0.221, -0.355, all P<0.05), and bilateral thalamus gray matter volume was negatively correlated with daily cigarette smoking (r=-0.186, P<0.05). Conclusion: The changes of brain structure of smokers mainly occur on reward-related pathways and marginal systems, and related to accumulation of cigarette smoking.