Huan-Huan Su

Regional homogeneity changes in heroin-dependent individuals: resting-state functional MR imaging study.

PURPOSE To identify heroin-related modulations of neural activity in the resting state in heroin-dependent individuals (HDIs) by using resting-state functional magnetic resonance (MR) imaging and a regional homogeneity method and to investigate whether these changes of neural activity can be related to duration of heroin use and to decision-making deficits in HDIs. MATERIALS AND METHODS This prospective study was approved by the appropriate ethics committee, and written informed consent was obtained from each participant. Thirty-one HDIs receiving methadone-maintained treatment and 24 control subjects participated. Resting-state functional MR imaging was performed by using a gradient-echo echo-planar imaging sequence. Regional homogeneity was calculated by using software. Voxel-based analysis of the regional homogeneity maps between control and HDI groups was performed with two-sample t tests by using software. Statistical maps were set at P less than .05 and were corrected for multiple comparisons. The Iowa gambling task (IGT) was used to assess participant decision making during uncertainty. Abnormal clusters revealed by group comparison were extracted and correlated with behavioral performance at the IGT and with duration of heroin use. RESULTS Regional homogeneity was diminished in the bilateral medial orbitofrontal cortex (OFC), bilateral dorsal medial thalamus, bilateral cuneus, and lingual gyrus in HDIs compared with control subjects. There were negative correlations between mean regional homogeneity in the medial OFC, bilateral cuneus, and lingual gyrus and duration of heroin use. There was a positive correlation between mean regional homogeneity in the medial OFC and performance level at the IGT. CONCLUSION The present study reveals resting-state abnormalities in HDIs that may lead to further improvement of the understanding of the neural substrates of cognitive impairment in HDIs.

Progressive white matter microstructure damage in male chronic heroin dependent individuals: a DTI and TBSS study.

Background To investigate the WM microstructure deficits in heroin dependent individuals (HDIs) with different length of heroin dependence, and to investigate whether these WM deficits can be related to the duration of heroin use and to decision-making deficits in HDIs. Methodology/Principal Findings Thirty-six HDIs [including eighteen sHDIs (duration of heroin dependent is less than 10 years) and eighteen lHDIs (duration of dependent is between 10∼20 years)] and sixteen healthy controls participated in this study. Whole brain voxel-wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da) and radial diffusivity (Dr) were performed by tract-based spatial statistics (TBSS) to localize abnormal WM regions among groups. TBSS demonstrated that sHDIs had significantly lower FA than controls in right orbito-frontal WM, bilateral temporal WM and right parietal WM. The lHDIs had significantly lower FA throughout the brain compared with the controls and sHDIs. The lHDIs had significantly lower Da than controls in bilateral inferior frontaloccipital fasciculus, bilateral splenium of corpus callosum, left inferior longitudinal fasciculus, and had significantly higher Dr than controls in bilateral uncinatus fasciculus, bilateral inferior frontaloccipital fasciculus and bilateral cortical spinal fasciculus. Volume-of-interest (VOI) analyses detect the changes of diffusivity indices in the regions with FA abnormalities revealed by control vs sHDIs. In most VOIs, FA reductions were caused by the increase in Dr as well as the decrease in Da. Correlation analysis was used to assess the relationship between FA and behavioral measures in HDIs and controls available. Significantly positively correlations were found between the FA values in the right orbital-frontal WM, right parietal WM and IGT performance. Conclusions The extent and severity of WM integrity deficits in HDIs was associated with the length of heroin dependent. Furthermore, abnormal WM microstructure may correlate with decision-making impairments in HDIs.

The impulsivity behavior is correlated with prefrontal cortex gray matter volume reduction in heroin-dependent individuals

PURPOSE Chronic exposure to heroin induced cerebral structural abnormalities may underlie heroin-related behaviors. The aim of this study was to: (1) identify cerebral structural abnormalities in heroin-dependent individuals (HDIs) by an automated and unbiased morphometric technique. (2) Define the correlation between these cerebral structural abnormalities and the impulsivity characteristic in HDIs. METHODS 24 HDIs and 24 control subjects were completed with (1) high resolution structural magnetic resonance imaging scanning and analysis of gray matter volume using voxel-based morphometry implemented in Statistical Parametric Mapping and (2) a Chinese translation Barratt Impulsiveness Scale-11 questionnaire survey. Differences in regional gray matter volume were tested using an analysis of covariance model, co-varying for global gray matter and age. Statistical maps were set at p<0.05, corrected for multiple comparisons. The abnormal brain regions were correlated with the duration of heroin use and impulsivity scores. RESULTS After adjusting for effects of age and total gray matter volume, cortical gray matter volume in the bilateral medial prefrontal cortex, bilateral dorsal lateral prefrontal cortex, and right fusiform cortex were significantly reduced in HDIs. Moreover, the gray matter volume in prefrontal cortex that showed group differences was negatively correlated with the duration of heroin use and negatively correlated with the impulsivity characteristic in HDIs. CONCLUSION These findings reveal the prefrontal cortex was impaired in HDIs, meanwhile, indicate the changes in gray matter volume are relating to the duration of heroin use and the impulsivity characteristic of the HDIs.

Abnormal regional homogeneity of resting-state brain activity in patients with HBV-related cirrhosis without overt hepatic encephalopathy.

Many studies have reported that cognitive deficits exist in cirrhotic patients without overt hepatic encephalopathy (OHE). However, the neurobiological mechanisms underlying these deficits are still not fully understood.

Structural and functional brain alterations in end stage renal disease patients on routine hemodialysis: a voxel-based morphometry and resting state functional connectivity study.

Background and Purpose Cognitive impairment is a well-described phenomenon in end-stage renal disease (ESRD) patients. However, its pathogenesis remains poorly understood. The primary focus of this study was to examine structural and functional brain deficits in ESRD patients. Materials and Methods Thirty ESRD patients on hemodialysis (without clinical neurological disease) and 30 age- and gender-matched control individuals (without renal or neurological problems) were recruited in a prospective, single-center study. High-resolution structural magnetic resonance imaging (MRI) and resting state functional MRI were performed on both groups to detect the subtle cerebral deficits in ESRD patients. Voxel-based morphometry was used to characterize gray matter deficits in ESRD patients. The impact of abnormal morphometry on the cerebral functional integrity was investigated by evaluating the alterations in resting state functional connectivity when brain regions with gray matter volume reduction were used as seed areas. Results A significant decrease in gray matter volume was observed in ESRD patients in the bilateral medial orbito-prefrontal cortices, bilateral dorsal lateral prefrontal cortices, and the left middle temporal cortex. When brain regions with gray matter volume reduction were used as seed areas, the integration was found to be significantly decreased in ESRD patients in the fronto-cerebellum circuits and within prefrontal circuits. In addition, significantly enhanced functional connectivity was found between the prefrontal cortex and the left temporal cortex and within the prefrontal circuits. Conclusions Our study revealed that both the structural and functional cerebral cortices were impaired in ESRD patients on routine hemodialysis.

Reduced ventral medial prefrontal cortex (vmPFC) volume and impaired vmPFC-default mode network integration in codeine-containing cough syrups users

OBJECTIVE To characterize the association between clinical symptoms and anatomical and functional cerebral deficits in codeine-containing cough syrups (CCS) users using voxel-based morphometry and resting state functional connectivity analysis. METHODS Participants were 30 CCS users and 30 matched controls. Both groups were scanned using a volumetric three-dimensional fast field echo sequence and a gradient-echo echo-planar imaging sequence. Impulsivity traits of both groups were evaluated with the Barratt Impulsiveness Scale 11 (BIS 11). Voxel-based morphometry was used to characterize gray matter (GM) deficits in CCS users. The clinical significance of regional volume reduction was investigated by evaluating its association with impulsivity in CCS users and with alterations in resting state functional connectivity when brain regions with GM volume reduction were used as seed areas. RESULTS Significantly decreased GM volume was observed in CCS users in bilateral ventral medial prefrontal cortex (vmPFC) which was related to greater impulsivity in CCS users. Significantly decreased integration was found in CCS users between the vmPFC and the default mode network. Also, significantly enhanced functional connectivity was found between the vmPFC and the right insula, and the right dorsal lateral PFC. Negative correlation was observed between BIS total scores, scores for attentional impulsivity and vmPFC-inferior parietal lobe connectivity in CCS users. CONCLUSIONS The findings revealed volume loss and aberrant functional organization in vmPFC among CCS users. In addition, the decreased vmPFC GM volume and attenuated functional connectivity of the vmPFC-inferior parietal lobe network were associated with clinical higher impulsivity trait in CCS users.

Regional homogeneity changes in hemodialysis patients with end stage renal disease: in vivo resting-state functional MRI study.

Objective To prospectively investigate and detect early cerebral regional homogeneity (ReHo) changes in neurologically asymptomatic patients with end stage renal disease (ESRD) using in vivo resting-state functional MR imaging (Rs-fMRI). Methods We enrolled 20 patients (15 men, 5 women; meanage, 37.1 years; range, 19–49 years) with ESRD and 20 healthy controls (15 men, 5 women; mean age, 38.3 years; range, 28–49 years). The mean duration of hemodialysis for the patient group was 10.7±6.4 monthes. There was no significant sex or age difference between the ESRD and control groups. Rs-fMRI was performed using a gradient-echo echo-planar imaging sequence. ReHo was calculated using software (DPARSF). Voxel-based analysis of the ReHo maps between ESRD and control groups was performed with a two-samples t test. Statistical maps were set at P value less than 0.05 and were corrected for multiple comparisons. The Mini-Mental State Examination (MMSE) was administered to all participants at imaging. Results ReHo values were increased in the bilateral superior temporal gyrus and left medial frontal gyrus in the ERSD group compared with controls, but a significantly decreased ReHo value was found in the right middle temporal gyrus. There was no significant correlation between ReHo values and the duration of hemodialysis in the ESRD group. Both the patients and control subjects had normal MMSE scores (≥28). Conclusions Our finding revealed that abnormal brain activity was distributed mainly in the memory and cognition related cotices in patients with ESRD. The abnormal spontaneous neuronal activity in those areas provide information on the neural mechanisms underlying cognitive impairment in patients with ESRD, and demonstrate that Rs-fMRI with ReHo analysis is a useful non-invasive imaging tool for the detection of early cerebral ReHo changes in hemodialysis patients with ESRD.

Intrinsic brain network abnormalities in codeine-containing cough syrup-dependent male individuals revealed in resting-state fMRI

To identify codeine‐containing cough syrups (CCS)‐related modulations of intrinsic connectivity network (ICN) and to investigate whether these changes of ICN can be related to duration of CCS use and to impulsivity behavior in CCS‐dependent individuals.

Larger corpus callosum and reduced orbitofrontal cortex homotopic connectivity in codeine cough syrup-dependent male adolescents and young adults

AbstractObjectivesTo characterize interhemispheric functional and anatomical connectivity and their relationships with impulsive behaviour in codeine-containing cough syrup (CCS)-dependent male adolescents and young adults.MethodsWe compared volumes of corpus callosum (CC) and its five subregion and voxel-mirrored homotopic functional connectivity (VMHC) in 33 CCS-dependent male adolescents and young adults and 38 healthy controls, group-matched for age, education and smoking status. Barratt impulsiveness scale (BIS.11) was used to assess participant impulsive behaviour. Abnormal CC subregions and VMHC revealed by group comparison were extracted and correlated with impulsive behaviour and duration of CCS use.ResultsWe found selective increased mid-posterior CC volume in CCS-dependent male adolescents and young adults and detected decreased homotopic interhemispheric functional connectivity of medial orbitofrontal cortex (OFC). Moreover, impairment of VMHC was associated with the impulsive behaviour and correlated with the duration of CCS abuse in CCS-dependent male adolescents and young adults.ConclusionsThese findings reveal CC abnormalities and disruption of interhemispheric homotopic connectivity in CCS-dependent male adolescents and young adults, which provide a novel insight into the impact of interhemispheric disconnectivity on impulsive behaviour in substance addiction pathophysiology.Key Points• CCS-dependent individuals (patients) had selective increased volumes of mid-posterior corpus callosum • Patients had attenuated interhemispheric homotopic FC (VMHC) of bilateral orbitofrontal cortex • Impairment of VMHC correlated with impulsive behaviour in patients • Impairment of VMHC correlated with the CCS duration in patients