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Objective:To explore the grey matter concentration in individuals with cognitive vulnerability to depression.Methods:Thirty individuals with cognitive vulnerability to depression and thirty age-and gender-matched healthy controls were enrolled in this study,and they were subjected to magnetic resonance imaging (MRI) examination.The grey matter concentration differences were compared between the two groups by using voxel-based morphometry (VBM) following MRI.Results:Individuals with cognitive vulnerability to depression showed significantly lower grey matter density in bilateral insular,left cerebellum,right supplementary motor area,and left precentral gyrus than those in the healthy controls,while the healthy controls showed significantly lower grey density in the right inferior frontal gyrus,right middle frontal gyrus,and left cuneus than those in the individuals with cognitive vulnerability to depression.Conclusion:Structural brain abnormalities in individuals with cognitive vulnerability to depression might be the neural basis for cognitive vulnerability to depression.
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Objective To examine the effects of a functional polymorphism of the monoamine oxidase A (MAOA) gene on spontaneous brain activity in healthy male adolescents.Methods Resting-state fMRI was performed on 31 healthy male adolescents with the low-activity MAOA genotype (MAOA-L) and 25 healthy male adolescents with the high-activity MAOA genotype (MAOA-H).The amplitude of low-frequency fluctuation (ALFF) of the blood oxygen level-dependent (BOLD) signal was calculated using REST software,and was compared between two genotype groups.The region ROIs showed significant difference.The ALFF data in ROIs were related to BIS scores.Results Compared with the MAOA-H group,the MAOA-L group showed a significant decrease of ALFF (P＜0.001) in the pons (MNI coordinates:-6,-19,-23;6,-16,-17;-6,-25,-32).In addition,the BIS scores were positively correlated with ALFF in pons in the MAOA-L group (r=0.398,P=0.02),but not in the MAOA-H group.Conclusions There exists relevance between the polymorphism of MAOA and the spontaneous brain activity in pons.And the lower activity of spontaneous brain activity in pons may be a key risk factor for impulsivity and aggression.
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OBJECTIVE@#To evaluate dynamic contrast-enhanced MRI in conjunction with MR subtraction in the differential diagnosis of benign and malignant breast tumors at 3 Tesla.@*METHODS@#A total of 78 patients with breast tumors enrolled in this study, including 45 malignant lesions and 33 benign lesions verified by histopathology. Dynamic MR contrast enhanced imaging was done by T1 high resolution isotropic volume excitation sequence. MR subtraction was used to retrospectively analyze the MR dynamic image. A dynamic phase subtraction (DPS) map is a map image with pixel-by-pixel subtraction of an early-phase image from a delayed maximum enhancement phase image obtained in a dynamic study. The sensitivity and specificity were calculated with or without subtraction in the diagnosis of benign and malignant breast tumors.@*RESULTS@#The sensitivity of benign breast masses increased from 0.879 to 0.939, and the specificity increased from 0.818 to 0.909 with reference to the DPS map. There was statistical difference between with or without DPS (Z=2.023, P=0.043). The sensitivity of breast malignant masses increased from 0.889 to 0.933, and the specificity increased from 0.867 to 0.911 with reference to the DPS map, with statistical difference between with or without DPS map (Z=2.294, P=0.021). The pattern of TIC changed from continuous to a plateau in 8 patients, from a plateau to washout in 10, and from continuous to washout in 5. No changes were observed in the other 55 patients.@*CONCLUSION@#MR Subtraction is a simple and useful technique to identify breast lesions. It helps to accurately set the location of the ROI TIC and improve the detection rate of benign and malignant breast tumors.
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Female , Humans , Breast Neoplasms , Diagnosis , Contrast Media , Diagnosis, Differential , Image Enhancement , Magnetic Resonance Imaging , Retrospective Studies , Sensitivity and SpecificityABSTRACT
Objective To observe the change of MR perfusion value in patients with hepatocellular carcinoma (HCC) before and after transcatheter arterial chemoembolization (TACE). Methods A total of 22 patients with HCC underwent MR perfusion weighted imaging (MR PWI) before TACE and 3-10 days after TACE. The mean time to enhance (MTE), negative enhancement integral (NEI), time to peak (TTP) and maximum slope of decrease (MSD) before and after TACE were acquired and compared. Results The time intension curve (TIC) of HCC region was observed to descend rapidly before TACE, while descended slowly after TACE. The value of MTE and TTP after TACE were lower than those before TACE (P0.05). Conclusion MR PWI is a very sensitive imaging technique that be used to monitor blood flow changes of HCC before and after TACE and evaluate efficacy of TACE.
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Objective To investigate the value of MR perfusion imaging in early detection of findings following arterial chemoembolization of hepatocellular carcinoma Methods Twenty eight consecutive patients with pathologically-confirmed HCC were evaluated. All patients underwent MR perfusion imaging at pre-TACE and 3 to 10 days after TACE. The negative enhancement integral (NEI) ,the time to peak(TTP) ,the maximum slope of decrease (MSD) , the signal enhance ratio (SER) were acquired from MRI software FuncTool 2. 5.36a Version. Statistical analysis using SPSS 14, least significant difference test (t test) were utilized. Results The time intensive curve of tumor was observed to descend rapidly to reach the peak at pre-TACE studies, whereas it descended slowly to reach the peak on post TACE studies. The Value of TTP and SER prior to TACE were(51.2 ± 10. 3) s, 60. 6 ± 36. 3 respectively, and post TACE (43.7 ± 12. 0)s, 41.2 ±27. 5 respectively. The values of TTP and SER post TACE were lower than those prior to TACE (P ＜ 0. 05). The value of NEI prior to TACE was 108.7 ± 58.9, and after TACE 149. 6 ±80. 1 and there was statistically significant difference (P ＜0. 05). The Value of MSD post TACE were lower than those prior to TACE, but there was no statistical significance (P ＞ 0. 05). Conclusion PWI is a very sensitive imaging technique that can be used to monitor early dynamic changes of HCC following TACE.
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Objective To assess metabolic alterations in the human basal ganglia area during maturation and aging by using 2D chemical shift imaging (2D CSI) of proton magnetic resonance spectroscopy (1H-MRS). Methods Seventy healthy subjects were examined by 2D CSI. 2D CSI imaging acquisition was performed in the bilateral caudate, lentiform and thalamus. 1H-MRS was processed to determine the metabolite ratios, including NAA/Cho, NAA/Cr, Cho/Cr. Seventy healthy subjects were divided into 3 groups:20 to 39 years of age group, 40 to 59 years of age group and 60 to 87 years of age group. The three groups of healthy participants were compared. Results There was a significant decrease with aging in the NAA/Cho ratio in the bilateral lcntiform, thalamus and left caudate, and a significant decrease with aging in NAA/Cr ratio in the bilateral thalamus,right lentiform and left caudate (P<0.05), whereas the Cho/Cr ratio was significantly increased in the bilateral lentiform with aging(P<0.05). Conclusions The results of 1H-MRS show significant changes in the level of metabolites during the process of aging. This technique may play an important role in clinical studies and applications for various conditions of metabolic disorders of the human brain.
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Objective To evaluate the diagosis value of different spiral computed tomography(CT) chest scanning methods in the differentiation of various pulmonary diseases,in order to avoid x-ray irradiation damage and reduce patients economic burden,but the diagnosis criterion should be guaranteed still.Methods 1000 cases of chest scan by spiral CT were randomly analyzed.In 927 conventional scan cases,including 155 cases of simple plainscan,474 cases of direct contrast scan,25 cases of plain plus contrast scans,73 cases of CT angiography.In addition,high resolution CT(HRCT) for 105 cases,thin layer scan for 86 cases,dynamic scan for 6 cases,and 40 cases bronchgraphy diagnosis were also carried out in the conventional scanning cases.Results The different CT scanning methods were adapted for diffenent pulmonary diseases.An adaptive scanning method and technique can decrease X-ray irradiation dosage and rise accuracy of diagnosis.Conclusions Aptimal scanning method and technique should be alternative according the clinical need and the patients status.
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Objective To analyze the diffusion properties of acute cerebral stroke to understand the effects of infarct and hematoma on diffusion-weighted MR images of patients with acute cerebral stroke. Methods 25 acute cerebral infarcts, 22 intracranial hematomas and 5 hemorrhagic infarctions were studied with CT, conventional and diffusion MR imaging. The DWI and ADC parameters of acute cerebral stroke were analyzed. Results The DWI images of 25 acute cerebral infarcts, 1 hyperacute hematoma, 2 acute hematomas and 3 subacute hematomas were hyperintensity, and that of 8 early subacute hematomas were hypointensity. The DWI images of early stage of 4 chronic hematomas were hyperintensity at center and hypointensity at periphery, and that of late stage were hypointensity. The DWI images of acute hemorrhagic infarctions had both the hyperintensity and hypointensity. Meanwhile, the ADC images of majority of the lesions were hypointensity. Conclusion DWI could reflect the diffusion properties of different types of cerebral strokes and play an important role in evaluating the strokes.
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Objective To investigate the clinical application of magnetic resonance cholangiopancreatography(MRCP) in diagnosis of obstructive jaundice.Methods Thirty-three patients with obstructive jaundice were examined by MRCP and the accurate rate of MRCP was evaluated according to the result of operation and pathology examination.Results The positive rate of the orientation diagnosis of MRCP in obstruction was 100%(33/33).The accurate rates of qualitative diagnosis for benign disease and malignant obstructive jaundice were 87.5%(21/24) and 90%(9/10) respectively.The general qualitative diagnose accordance rate was 87.9%(29/33).Conclusion MRCP is simple,hurtless and safe for the diagnosis of obstructive jaundice and it deserves generalization in the clinical application.
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Objective To evaluate the role of three-dimensional multi-tissues (3DMT) CT reconstruction in imaging atlantoaxial and atlantooccipital deformities or traumas.Methods 10 normal volunteers and 42 patients with atlantoaxial and atlanoccipital deformities or traumas underwent spiral CT scan, then three-dimensional (surface shaded display, SSD) CT reconstruction and three-dimensional multi-tissues (3DMT) CT reconstruction.Results SSD and 3DMT reconstruction clearly demonstrated the anatomy of the bony structures and the spatial relationships between the occipitale and atlas, atlas and axis. 3DMT reconstruction respectively demonstrated the occipitale, atlas and axis. 3DMT more neatly demonstrated the deformities, fractures and dislocations of atlantoaxial and atlantooccipital joint than SSD reconstruction. Conclusion 3DMT CT illustrates the anatomical relationship of atlantooccipital and atlantoaxial complex and provides important information of the pathology. 3DMT is prior to SSD reconstruction.