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Objective:To investigate the differences of spontaneous neural activity and functional connectivity between bilateral symmetrical voxels in the local brain regions at resting-state of methamphetamine (MA) dependent patients and healthy controls (HCs).Methods:Forty-six MA-dependent patients, admitted to and received drug rehabilitation treatment for the first time in our hospital from February 2014 to October 2019, and 46 HCs matched with age, gender and education level during the same period were enrolled in this study. The resting state functional magnetic resonance imaging (rs-fMRI) data of these subjects were collected; the static and dynamic regional homogeneity (ReHo, d-ReHo) and static and dynamic voxel-mirrored homotopic connectivity (VMHC, d-VMHC) were used to evaluate MA-related alterations of brain spontaneous activity and interhemispheric functional connectivity. The correlations of brief psychiatric rating scale (BPRS) scores with above values in the brain regions with significant inter-group differences were analyzed.Results:As compared with the HCs, the MA-dependent patients had significantly decreased ReHo in the left medial orbitofrontal cortex (mOFC), and significantly increased d-ReHo in the left mOFC, left middle frontal gyrus, bilateral inferior frontal gyrus, left precentral gyrus and left postcentral gyrus ( P<0.05). As compared with the HCs, the MA-dependent patients had significantly decreased VMHC in the bilateral mOFC, precentral gyrus and postcentral gyrus ( P<0.05). The ReHo, VMHC, d-ReHo, and d-VMHC were not significantly correlated with total scores and each factor scores of BPRS, and total dose of MA (after removing outliers) in MA-dependent patients ( P>0.05). Conclusion:During resting state, MA-dependent patients show obvious abnormalities in the coordination and stability of spontaneous neural activity and the coordination of interhemispheric activity in local brain regions, especially in the mOFC; abnormal ReHo, d-ReHo and VMHC in left mOFC may be important neuroimaging biomarkers for MA-dependence.
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Objective:To investigate the topological alterations of brain functional networks in patients with chronic methamphetamine (MA) dependence.Methods:Resting-state functional magnetic resonance imaging was used to map the brain networks of 46 patients with MA-dependence (MA group) and 46 healthy controls (control group). Statistical methods were used to compare the differences of brain functional connection and topological parameters between the two groups, and the correlations between these topological parameters with significant inter-group differences and clinical measurements were analyzed.Results:(1) Brain functional connection: as compared with the control group, the MA group had significantly enhanced functional connectivity in the subnetworks consisting of several brain regions, including the inferior parietal lobule, posterior central gyrus, lateral occipital cortex, ventromedial occipital cortex, orbital gyrus, anterior central gyrus, fusiform gyrus, superior temporal gyrus and thalamus; as compared with the control group, the MA group had significantly attenuated functional connectivity in the subnetworks consisting of several brain regions, the orbit frontal cortex, precentral gyrus, paracenter lobule, inferior temporal gyrus, fusiform gyrus, parahippocampal gyrus, superior parietal lobule, postcentral gyrus, medioventral occipital cortex, lateral occipital cortex and amygdala. (2) Network topology attributes: the brain functional networks in all subjects from the MA group and control group held worldlet; but attribute of worldlet in the MA group was significantly reduced as compared with that in the control group ( P<0.05); moreover, the MA group had significantly decreased clustering coefficient, local efficiency, and modularity as compared with the control group ( P<0.05). In terms of regional topological attributes, such as betweenness centrality, the MA group presented evident reduction in the left superior frontal gyrus, right orbit frontal cortex, right middle temporal gyrus and right/left lateral occipital cortex as compared with the control group with significant differences ( P<0.05). (3)Correlation analysis: the betweenness centrality of right middle temporal gyrus exhibited a positive correlation with the age of patients using MA for the first time ( r=0.327, P=0.028); a positive correlation was found between the modularity and activating factor scores in Brief Psychiatric Rating Scale (BPRS) in MA group ( r=0.315, P=0.035). Conclusions:Part of the global/local topological attributes of the brain functional network of patients with MA addiction are damaged. The younger the patients are when they take MA for the first time, the lower the betweenness centrality of the right middle temporal gyrus; the more the local attributes are damaged; and furthermore, the deeper the network modularity, the severer the active symptoms in the psychotic symptoms.
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Objective To investigate the relationship between single b-value and multiple b-value diffusion weighted imaging (DWI)and different types of breast lesions.Methods The data of 92 cases including 8 cases of cyst,11 cases of granulomatous inflammation,33 cases of benign nodules lesions and 40 cases of malignant tumor were analyzed retrospectively,who underwent single b-value DWI and multiple b-value DWI and all patients were confirmed by pathology.The normal side of the mammary gland fiber was taken as the control group.Apparent diffusion coefficient(ADC)were obtained by the monoexponential model.Slow apparent diffusion coefficient(ADCslow),fast apparent diffusion coefficient(ADCfast),the fraction of fast ADC(ffast)were obtained by the biexponential model.ADC,ADCslow,ADCfast,ffastvalues of different breast lesions were analyzed by single factor analysis of variance.The LSD-t test was used to compare the mean values of the parameters of the breast lesions in pairs.Results The ADC and ADCslowvalue of breast lesions were decreased in the order of cyst (2.369 ± 0.380)×10-3mm2/s,(1.294 ± 0.439)×10-3mm2/s,normal gland(1.785 ± 0.298)×10-3mm2/s,(0.946 ± 0.321)×10-3mm2/s,benign tumor(1.647 ± 0.296)×10-3mm2/s,(0.944 ± 0.256)×10-3mm2/s,malignant tumor(1.146 ± 0.191)×10-3mm2/s,(0.584 ± 0.139)×10-3mm2/s and mastitis(1.062 ± 0.231)×10-3mm2/s,(0.567 ± 0.115)×10-3mm2/s.The ADCfastvalue of malignant group(4.445 ± 1.616)×10-3mm2/s was significantly higher than that of other groups,and the difference was statistically significant.The ffastvalue of malignant group 0.364 ± 0.148 was significantly lower than that of benign group,normal gland and cyst.ADCfastvalue in the inflammatory group(3.321 ± 0.660)× 10-3mm2/s was significantly lower than that in the malignant group,and the difference was statistically significant.There was no significant difference in ADC,ADCslowand ffast.Conclusion Compared with the single b-value DWI,the parameters of multiple b-value DWI reflected the pathological features of different breast lesions better.The value of ADCfasthas higher diagnostic value in the identification of mastitis and breast cancer.
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Objective To evaluate the value of MR threedimensional arterial spin labeling (3D-ASL) perfusion imaging and intravoxel incoherent motion(IVIM) DWI in differential diagnosis and quantitative analysis of musculoskeletal tumors.Methods Forty-four patients with musculoskeletal tumors were included.According to pathologic results,there were 12 cases of benign tumors,10cases of intermediate tumors and 22 cases of malignant tumors.3D-ASL and IVIM DWI were both performed on forty-four patients to gain tumor blood flow (TBF),standard ADC (ADCstandard),slow ADC (ADCslow)and fast ADC (ADCfast).Immunohistochemical staining of specimens was performed by using CD34 monoclonal antibody to calculate microvessel density (MVD) counts.MVD,TBF,ADCfast and ADCslow of different groups were compared by one-way ANOVA analysis.ADCstandard was compared by Kruskal-Wallis test.ROC curve was used to analyze ASL and IVIM DWI,in order to determine the threshold and diagnostic reliability.Results The MVD of benign tumors was 10±4,the MVD of intermediate tumors was 15±6,and malignant tumors was 33 ± 1 1.There was significant difference among three groups of MVD(F=28.33,P＜0.05).There was better intra-observer agreement for ADCstandard,ADCfast,ADCslow and TBF(ICC=0.970,0.885,0.778,0.891,respectively,P＜0.05).The TBF of benign tumors was(30±10)ml· min-1· 100 g-1,intermediate tumors was(30± 12) ml·min 1· 100 g-1,and malignant tumors was(84±29)ml·min 1· 100 g-1.There was significant difference among three groups of TBF(F=32.34,P＜0.05).According to the ROC analysis,when the cut-offvalue of TBF was 45.5 ml·min-1· 100 g-1,the area under ROC curve was 0.95 1,and the sensitivity and specificity of TBF in diagnosing malignant tumors were 90.9％ and 95.5％ respectively.There was no significant difference among three groups of ADCstandard,ADCfastand ADCslow of benign tumors were(9.9±5.1)× 10-3,(1.9±0.5) × 10-3mm2/s respectively.ADCfast and ADCalow of intermediate tumors were(8.2 ± 3.6) × 10-3,(1.5 ± 0.6) × 10-3mm2/s respectively.ADCfast and ADCalow of malignant tumors were (16.9 ± 5.8) × 10 3,(1.4 ± 0.6) × 10-3mm2/s respectively.There were significant difference of ADCfast and ADCslow among three groups (F=12.75,5.60,P＜ 0.05).According to the ROC analysis,when the cut-off value of ADCfast was 9.4× 10-3mm2/s,the area under ROC curve was 0.861,the sensitivity and specificity of them in diagnosing malignant tumors were 95.5％ and 68.2％ respectively.Conclusion 3D-ASL and IVIM DWI are valuable in the differential diagnosis of musculoskeletal tumors.
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Objective To explore the relationship between the tumor angiogenesis index (microvessel density,MVD)and biological behavior of the tumor.To analyze the correlations between TBF,standard ADC,fast ADC,slow ADC and MVD counts.Methods From March 2013 to June 2013,a total of 40 patients were involved in the study.3D-ASL and IVIM DWI were both performed on patients with musculoskeletal tumors.TBF,standard ADC,slow ADC,fast ADC were measured by regions of interest.Immunohistochemical staining of specimens were performed by using CD34 monoclonal antibody to calculate MVD counts.Group differences in MVD were assessed by using one-way ANOVA.The correlations between TBF,standard ADC,fast ADC,slow ADC and MVD counts were evaluated using Pearson correlative analysis.Results The MVD of benign tumors was (10.38±4.58)/0.26 mm2,the MVD of intermediate tumors was (14.64±6.69)/0.26 mm2,and the MVD of malignant tumors was (32.97±11.61)/0.26 mm2.The differences of MVD among three groups were statistically significant (F=28.83,P＜0.05).The differences of MVD between benign and malignant group were statistically significant (P＜0.05),as well as intermediate and malignant group (p=0.000).There was a significant positive correlation between TBF and MVD (r=0.784,P=0.000),as well as the correlation between TBF and fast ADC(r=0.727,P=0.000).There was a moderate positive correlation between fast ADC and MVD (r=0.516,P=0.000).There were no significant correlation between slow ADC and MVD,or between standard ADC and MVD.Conclusion The MVD represents the angiogenesis of musculoskeletal tumors,reflecting biological behavior of the tumor.ASL and IVIM DWI can be applied to evaluate the angiogenesis of musculoskeletal tumors by reflecting MVD of musculoskeletal tumors in vivo as a completely noninvasive technique.
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Objective To analysis the imaging findings of tetralogy of Fallot and related pathological basis. Methods The clinical,pathologic and right ventriculography findings of 124 tetralogy of Fallot which were confirmed by surgery were retrospectively aralyzed. Results 124 tetralogy of Fallot were separated into type Ⅰ 62, Ⅱ 31, Ⅲ 6, Ⅳ 25 by Gray's classification,and slight,midrange,severe stenosis were 71 (0.51～0.6) ,33(0.41～0.5) ,20(<0.4) by Partiole's classcification. As to ventricular septal defect(VSD) ,infra-cristal ventricular septal defect were found in 116/124 in which crista supravcntricalaris appeared as girdle-shaped filling defect in lateral position, suprac-ristal ventricular septal defect were found in 8/124 in which crista supraventricularis appeared as round filling defect in orthophoric position. Conclusions Right ventriculography can precisely display stenosis of pulmary and ventricular septal defect(VSD). It has great valne in diagnosis and surgical therapy of tetralogy of Fallot.
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The smoke of anti-infrared smoke agent in a self-made miniature smoke chamber was determined by using Forier transform infrared spectrometer. The smoke changing and settling regulation with time were obtained by measuring the IR spectra of smoke at different time dynamically. Through testing the smoke of different quantity of the same smoke agent, it was found that the relationship between the concentration of the main smoke products and the absorbance obeyed Lambert-Beer′s Law. Finally, the relationship between the smoke screening ability and reactant agent amounts was obtained by calculating the screening ability of different amounts of reactant agent in three “atmosphere windows”.
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Objective To investigate the value of MR perfusion-weighted imaging(PWI)in the evaluation of therapeutic effect of brain metastases with gamma knife.Methods Treatment by gamma knife before and after that 3 months or 6 months PWI studies were penformed respectively in 22 patients with brain metastases .Maps of relative regional blood volume(rCBV)and mean transit time(MTT)were obtained.The ratios of rCBV and MTT of lesions were analyzed.Results rCBV of tumors in 22 cases was increased.The ratios of maximum rCBV of the lesions and opposite side were 6.16?3.12 and 1.18?0.17 respectively.The ratios of MTT of the tumors was 1.44?0.53.After gamma knife treatment,9 of 22 cases appeared decreased rCBV,but the ratios of MTT were no changing,of them,3 cases presented cerebral necrosis.13 of 22 cases,the ratios of rCBV were increased in varied degree after treatment by gamma knife,and 6 cases presented brain radionecrosis.Conclusion PWI is a significant method in evaluating the therapeutic effect of brain metastases with gamma knife
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Objective To evaluate 1*"H magnetic resonance spectroscopy (1H MRS) in the differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis. Methods Fifteen patients who had clinical and CT, MRI changes that suggested a diagnosis of delayed cerebral necrosis or recurrent brain tumor after radiation therapy and 5 patients who had a definite clinical diagnosis of delayed cerebral necrosis underwent single voxel MR spectroscopy simultaneously both in the lesion′s region and the contralateral side. Results Of the former 15 cases who proved by surgicopathology, 14 cases were gliomas,1case was delayed cerebral necrosis, and their etiologic diagnoses of 1*"H MRS were correct. (1)1H MRS in 14 cases with gliomas exhibited specific spectral peaks including prominent choline-containing compounds (Cho), decreased or absent acetylaspartate(NAA) and total creatine (Cr),and the metabolic ratios showed significantly increased Cho/Cr, decreased NAA/Cr. Twelve cases showed abnormal lactate (Lac). (2)Among 6 cases with delayed cerebral necrosis, 5 cases exhibited decreased or absent Cho, NAA, Cr, and abnormal Lipid, 1 case showed absent Cho, NAA, and Cr with a flat curve without Lac. Conclusion 1H MRS was positively claimed for differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis.