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Objective To observe changes of brain function synchronized activity and gray matter structure alterations in patients with chronic subjective tinnitus (ST) with MRI.Methods Resting-state fMRI and 3D T1WI were obtained in 21 chronic ST patients (case group) and 21 healthy volunteers (control group).The voxel-based morphometry and regional homogeneity (ReHo) were used to analyze changes of the gray matter structure and volume.Results Compared with control group,ReHo values of the right superior,middle and inferior temporal gyrus increased in case group (P＜0.05),ReHo values of the right middle orbital frontal gyrus/inferior triangle frontal gyrus,left middle frontal gyrus/angular gyrus and cerebellar vermis decreased (P＜0.05),and the gray matter volume of the right middle temporal gyrus,superior dorsolateral frontal gyrus and left superior medial frontal gyrus decreased in case group (P＜0.01).Furthermore,Re Ho values of the right middle temporal gyrus were positively correlated with tinnitus handicap inventory scores (r=0.604,P=0.005) in case group.Conclusion The neural function synchronized activity and gray matter volume changes in the auditory and non-auditory brain regions of patients with chronic ST,providing references for finding possible neuroimaging markers.
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Objective To evaluate the potential cerebral cortical volume alterations in type 2 diabetes mellitus (T2DM) patients with mild cognitive impairment (MCI) compared with T2DM patients and healthy controls,and to observe the correlations with the scores of neuropsychological scales.Methods Cortical volume based on high-resolution MR T1WI data from 30 healthy controls (HC),30 T2DM patients and 30 T2DM with MCI patients were evaluated with FreeSurfer software and compared with variance analysis.The correlations between cerebral cortical volume which had statistical difference and the scores of neuropsychological scales were analyzed.Results There were significant differences in auditory verbal learning test (AVLT) scores,complex figure test-delayed recall (20 min) scores,digit symbol-coding subtest scores,MoCA scores and higher trail-making test-A scores,as well as trail-making test-B scores between T2DM and T2DM with MCI patients (all P＜0.05).Compared with T2DM patients,cortical volume of left entorhinal cortex,left lateral orbitofrontal gyrus,left posterior cingulate gyrus and the right lateral orbitofrontal gyrus,right pars orbitalis,right insula reduced in T2DM with MCI patients (all P＜0.05).In T2DM with MCI patients,AVLT scores were positively correlated with volume of the left entorhinal cortex (r=0.452,P=0.018).Conclusion Several cortical volume reductions are exhibited in T2DM patients with MCI.The volume of the left entorhinal cortex may be a potential biomarker to diagnose and evaluate MCI in T2DM.
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Objective To study the developmental process of the region of basal nuclei of postmortem fetuses by 3.0 T and 7.0 T MRI.Methods One hundred and thirty-one postmortem fetuses of 14 to 40 weeks of gestational age(GA)were scanned by 3.0 T MR,of which 11 fetuses of 14-27 weeks of GA were chosen and scanned by 7.0 T MR. The time when the structures in the region of basal nuclei could be detected and the changes of MR signal intensity were analyzed for MRI of different Tesla.Results On 3.0 T MRI.the dorsal thalamus could be delineated as early as 14 weeks of GA. The germinal matrix, caudate nucleus,and putamen could be visualized as early as 15 weeks of GA. The globus pallidus could be described as early as 18 weeks of GA.and the internal capsule and external capsule could be shown as early as 20 weeks of GA. The signal of the caudate nucleus during 15-30 weeks of GA was relatively hypointense on T1WI and hyperintense on T2WI.but during 31-40 weeks of GA, it was relatively hyperintense on T1WI and hypointense on T2WI. The putamen had a relatively high signal intensity on T1WI and low signal intemity on T1WI during 15-17 weeks of GA, and it appeared patchy during 18-25 weeks of GA,then it had a relatively low signal intensity on T1WI and high signal intensity on T2WI during 26-30 weeks of GA, and during 31-40 weeks of GA,its signal intensity was relatively high on T1WI and low on T2WI.The globus pallidus had a relatively high signal intensity on T1WI and low signal intensity on T2WI during 20-40 weeks of GA Compared to the 3.0 T MRI,the T2 images of 7.0 T MRl were more clear,and most structures in the region of basal nuclei could be clearly displayed as early as 16 weeks of GA.such as the germinal matrix,caudate nucleus,dorsal thalamus,putamen,globus pallidus,internal capsule,and external capsule.The claustrum could be delineated as early as 18 weeks of GA on 7.0 T MRI. Conclusions 3.0 T MRI could show the developmental process of the region of basal nuclei well,but the T2 images of 7.0 TMRl were comparatively better.