[Imaging changes in brain microstructural in long-term abstinent from methamphetamine-dependence]

To explore the mechanism for changes in brain microstructure in long-term abstinent from methamphetamine-dependence by using the diffusion tensor imaging (DTI).
 Methods: A total of 26 patients with long-term abstinent methamphetamine-dependence, whose abstinence time more than 14 months, and 26 normal controls all underwent cognitive executive function tests and DTI scans. We used voxel-based analysis to compare the fractional anisotropy (FA) and mean diffusivity (MD) to obtain the abnormal brain regions of DTI parameters between the two groups. Spearman correlation analysis was used to explore the correlation between FA, MD of the brain regions with abnormal parameters and cognitive executive function tests.
 Results: There were no statistical differences in the cognitive executive function tests between the two groups (P>0.05). Compared with the normal control group, the long-term abstinent from methamphetamine-dependence group showed the decreased FA in the right precuneus, right superior frontal gyrus, right calcarine, left inferior temporal gyrus and the increased MD in the right triangular part of inferior frontal gyrus, right precuneus, right posterior cingulate, right middle temporal gyrus, bilateral middle occipital gyrus, left superior parietal lobule, and lobule VIII of cerebellar hemisphere. The MD values of the right middle temporal gyrus in the long-term abstinent group were negatively correlated with the number of completions within 60 seconds (r=-0.504) and within 120 seconds (r=-0.464) .
 Conclusion: The DTI parameters in multiple brain regions from the methamphetamine-dependence patients are still abnormal after a long-term abstinence. DTI can provide imaging evidence for brain microstructural abnormalities in long-term abstinent from methamphetamine-dependence.