常规MRI和1H-MRS在职业性锰暴露致中枢神经损害中的应用价值

Objective MRI and MR hydrogen proton spectroscopy (1H-MRS) were used to detect the abnormal signal and alteration of metabolites, in order to explore the efficacy of these method in evaluating the damages of central nervous system (CNS) induced by occupational manganese exposure.Methods Eighteen workers exposed to manganese without any manganism symptoms, 12 workers with slightly chronic manganese poisoning, and 19 healthy workers were scanned using routine MRI sequence and 1H-MRS.The blood manganese concentration was also collected for each subject.On cerebral axial T1 WI,the signal intensities of ipsilateral globus pallidus and frontal white matter were measured in the visually brightest area (try to select the signal homogeneous region), and the globus pallidus index (PI) was then calculated.The 1H-MRS data was calculated to get the values of the peak height of N-acetylaspartate (NAA), choline (Cho), inositol (mI) and creatine (Cr) and the ratios of NAA/Cr, Cho/Cr, and mL/Cr were also calculated.One way ANOVA was used to compare the values of PI, NAA/Cr, Cho/Cr, mI/Cr and MnB among the three groups, and the correlations between PI and the time span of manganese exposure or blood manganese concentration were analyzed by Pearson correlation analysis.Eight workers exposed to manganese were followed up one year, and their PI , NAA/Cr before and after follow-up were compared by t test.Results Fourteen of 18 cases exposed to manganese without any manganism symptoms showed symmetrically high intensity signal on T1 WI, while the T2 WI were normal.No high signal intensity was observed on T1WI in any of the healthy workers or manganese poisoning workers.We found that the average PI in manganese exposed group (1.16 ±0.09) was significantly higher (F =24.79 ,P =0.O00)than those of the poisoning ( 1.05 ± 0.07 ) and control groups ( 1.01 ± 0.05 ).The blood manganese concentration in manganese exposed group, the poisoning group and the control group were (0.051 ±0.024), (0.047 ±0.018 ), ( 0.043 ± 0.020 ) μg/ml respectively, which was not significantly different ( F = O.623, P =0.541 ) and did not exceed the upper limit of normal reference value ( < 0.10 μg/ml ).There was a significantly correlation between PI and the time span of manganese exposure ( r = 0.67, P = 0.002 ),however, there was no correlation between PI and blood manganese concentration ( r = 0.20, P = 0.427 ).Furthermore, the NAA/Cr ratio decreased variously in the manganese poisoning group ( 1.22 ± 0.07 ) which was significantly lower( F = 4.120, P = 0.023 ) than those of the poisoning( 1.33 ± 0.13 ) and control groups ( 1.31 ±0.13).No statistical significanees were found in the ratios of Cho/Cr and mI/Cr among these three groups(P>0.05).No obvious changes of the PI and NAA/Cr were found in the 8 manganese exposed workers after 1 year follow-up.Conclusion Manganese exposure could lead to the high intensity signal on T1 WI, therefore the increased PI may be the biomarkers of central nerve system damages caused by the occupational manganese exposure.     

常规MRI和1H-MRS在职业性锰暴露致中枢神经损害中的应用价值

Objective MRI and MR hydrogen proton spectroscopy (1H-MRS) were used to detect the abnormal signal and alteration of metabolites, in order to explore the efficacy of these method in evaluating the damages of central nervous system (CNS) induced by occupational manganese exposure.Methods Eighteen workers exposed to manganese without any manganism symptoms, 12 workers with slightly chronic manganese poisoning, and 19 healthy workers were scanned using routine MRI sequence and 1H-MRS.The blood manganese concentration was also collected for each subject.On cerebral axial T1 WI,the signal intensities of ipsilateral globus pallidus and frontal white matter were measured in the visually brightest area (try to select the signal homogeneous region), and the globus pallidus index (PI) was then calculated.The 1H-MRS data was calculated to get the values of the peak height of N-acetylaspartate (NAA), choline (Cho), inositol (mI) and creatine (Cr) and the ratios of NAA/Cr, Cho/Cr, and mL/Cr were also calculated.One way ANOVA was used to compare the values of PI, NAA/Cr, Cho/Cr, mI/Cr and MnB among the three groups, and the correlations between PI and the time span of manganese exposure or blood manganese concentration were analyzed by Pearson correlation analysis.Eight workers exposed to manganese were followed up one year, and their PI , NAA/Cr before and after follow-up were compared by t test.Results Fourteen of 18 cases exposed to manganese without any manganism symptoms showed symmetrically high intensity signal on T1 WI, while the T2 WI were normal.No high signal intensity was observed on T1WI in any of the healthy workers or manganese poisoning workers.We found that the average PI in manganese exposed group (1.16 ±0.09) was significantly higher (F =24.79 ,P =0.O00)than those of the poisoning ( 1.05 ± 0.07 ) and control groups ( 1.01 ± 0.05 ).The blood manganese concentration in manganese exposed group, the poisoning group and the control group were (0.051 ±0.024), (0.047 ±0.018 ), ( 0.043 ± 0.020 ) μg/ml respectively, which was not significantly different ( F = O.623, P =0.541 ) and did not exceed the upper limit of normal reference value ( < 0.10 μg/ml ).There was a significantly correlation between PI and the time span of manganese exposure ( r = 0.67, P = 0.002 ),however, there was no correlation between PI and blood manganese concentration ( r = 0.20, P = 0.427 ).Furthermore, the NAA/Cr ratio decreased variously in the manganese poisoning group ( 1.22 ± 0.07 ) which was significantly lower( F = 4.120, P = 0.023 ) than those of the poisoning( 1.33 ± 0.13 ) and control groups ( 1.31 ±0.13).No statistical significanees were found in the ratios of Cho/Cr and mI/Cr among these three groups(P>0.05).No obvious changes of the PI and NAA/Cr were found in the 8 manganese exposed workers after 1 year follow-up.Conclusion Manganese exposure could lead to the high intensity signal on T1 WI, therefore the increased PI may be the biomarkers of central nerve system damages caused by the occupational manganese exposure.     

APP/PS1转基因阿尔茨海默病小鼠的MR波谱定量分析

Objective To explore changes of metabolites in APP/ PS1 double transgenie mice of Alzbeimer disease (AD) by 1H-MR spectroscopy (1H-MRS) and the application value of in early diagnosis of AD.Methods 1H-MRS was performed in 35 APP/PS1 transgenie mice of AD ( study group) and 20 wild type mice ( control group) at age of 3, 6 and 9 months using a 7.0 T MR system.Sub-peak areas of N-acetyl aspartate (NAA), myo-inositol (mI) and creatine (Cr) in the cerebral cortex and hippocampus were measured, and the NAA/Cr and mI/Cr ratios were calculated.The changes in pathology between the two groups were compared.Using the lower limit of 95% confidence interval (CI) of the ml/Cr ratio and the upper limit of 95% CI of the NAA/Cr ratio of AD mice as the threshold, their influences on sensitivity,specificity and accuracy of various age groups of AD animals were compared.Comparison of the 1H-MRS indexes between study mice and wild type mice at each time point were conducted by a two-sample t test.Results The mean mI/Cr ratios of AD mice were 0.68± 0.03, 0.72± 0.04, and 0.77 ± 0.04 respectively at 3, 6 and 9 months of age; while they were 0.63 ± 0.04, 0.64 ± 0.03, and 0.64 ± 0.04 respoetively in control group, the difference was significant ( t = 2.814, 5.146, 14.437, P < 0.01 ).Compared with the control group, the mI/Cr ratio of the 3-month-old AD mice of the study group was significantly increased,and histological examination showed proliferation and activation of neuroglial cells in the cerebral cortex and hippoeampus.The mean NAA/Cr ratio were 1.17 ±0.08, 1.04 ±0.05, and 0.90 ±0.05 respectively at 3,6 and 9 months of age in study group, while they were 1.18 ±0.07, 1.16 ±0.07, and 1.18 ±0.08respectively in control group.There were no significant difference ( t = 0.752, P > 0.05 ) between the study group and control group at 3 months of age, and the NAA/Cr ratio decreased significantly only at 6 and 9 months of age ( t = - 8.514, - 5.646, P < 0.01 ).The immunohistochemical exam demonstrated the appearance of Aβ plaque.According to threshold of mI/Cr, the sensitivity of AD mice of 3, 6 and 9 months of age was 80% (28/35), 84% ( 26/31 ) and 85% ( 23/27 ), and the specificity was 85% ( 17/20 ),94% (17/18) and 100% ( 16/16), and the accuracy was 82% (45/55), 88% (43/49) and 91% (39/43),respectively.For NAA/Cr, the sensitivity of AD mice of 6 and 9 months of age was 84% (26/31) and 89% (24/27), and the specificity was 89% (16/18) and 100% (16/16), and the accuracy was 86% (42/49) and 93% (40/43), respectively.Conclusions NAA and mI are the most sensitive and specific markers for early assessment of AD, and change of mI is earlier than that of NAA.Quantitative analysis of mI may provide important clues for early diagnosis of AD.     

APP/PS1转基因阿尔茨海默病小鼠的MR波谱定量分析

Objective To explore changes of metabolites in APP/ PS1 double transgenie mice of Alzbeimer disease (AD) by 1H-MR spectroscopy (1H-MRS) and the application value of in early diagnosis of AD.Methods 1H-MRS was performed in 35 APP/PS1 transgenie mice of AD ( study group) and 20 wild type mice ( control group) at age of 3, 6 and 9 months using a 7.0 T MR system.Sub-peak areas of N-acetyl aspartate (NAA), myo-inositol (mI) and creatine (Cr) in the cerebral cortex and hippocampus were measured, and the NAA/Cr and mI/Cr ratios were calculated.The changes in pathology between the two groups were compared.Using the lower limit of 95% confidence interval (CI) of the ml/Cr ratio and the upper limit of 95% CI of the NAA/Cr ratio of AD mice as the threshold, their influences on sensitivity,specificity and accuracy of various age groups of AD animals were compared.Comparison of the 1H-MRS indexes between study mice and wild type mice at each time point were conducted by a two-sample t test.Results The mean mI/Cr ratios of AD mice were 0.68± 0.03, 0.72± 0.04, and 0.77 ± 0.04 respectively at 3, 6 and 9 months of age; while they were 0.63 ± 0.04, 0.64 ± 0.03, and 0.64 ± 0.04 respoetively in control group, the difference was significant ( t = 2.814, 5.146, 14.437, P < 0.01 ).Compared with the control group, the mI/Cr ratio of the 3-month-old AD mice of the study group was significantly increased,and histological examination showed proliferation and activation of neuroglial cells in the cerebral cortex and hippoeampus.The mean NAA/Cr ratio were 1.17 ±0.08, 1.04 ±0.05, and 0.90 ±0.05 respectively at 3,6 and 9 months of age in study group, while they were 1.18 ±0.07, 1.16 ±0.07, and 1.18 ±0.08respectively in control group.There were no significant difference ( t = 0.752, P > 0.05 ) between the study group and control group at 3 months of age, and the NAA/Cr ratio decreased significantly only at 6 and 9 months of age ( t = - 8.514, - 5.646, P < 0.01 ).The immunohistochemical exam demonstrated the appearance of Aβ plaque.According to threshold of mI/Cr, the sensitivity of AD mice of 3, 6 and 9 months of age was 80% (28/35), 84% ( 26/31 ) and 85% ( 23/27 ), and the specificity was 85% ( 17/20 ),94% (17/18) and 100% ( 16/16), and the accuracy was 82% (45/55), 88% (43/49) and 91% (39/43),respectively.For NAA/Cr, the sensitivity of AD mice of 6 and 9 months of age was 84% (26/31) and 89% (24/27), and the specificity was 89% (16/18) and 100% (16/16), and the accuracy was 86% (42/49) and 93% (40/43), respectively.Conclusions NAA and mI are the most sensitive and specific markers for early assessment of AD, and change of mI is earlier than that of NAA.Quantitative analysis of mI may provide important clues for early diagnosis of AD.     

急性胆红素脑病常规MRI及~1H-MR波谱表现

目的 探讨急性胆红素脑病(acute bilirubin encephalopathy,ABE)患儿MRI特征及脑内代谢物含量与胆红素水平相关性.方法 对28例临床确诊为ABE新生儿(病例组)和15名正常新生儿(对照组)行T_1WI、T_2WI、DWI及~1H-MRS检查.~1H-MRS检查采用定点分辨率波谱序列,病例组28例均行基底节区多体素扫描,其中15例另行苍白球区单体素扫描.对照组15名新生儿均进行多体素及单体素~1H-MRS检查,测定代谢产物包括N-乙酰天冬氨酸(NAA)、肌酸复合物(Cr)、胆碱复合物(Cho)、肌醇(mI)、乳酸(Lac)、谷氨酸及谷氨酰胺复合物(Glx)浓度.并计算NAA/Cr、Cho/Cr、Lac/Cr、Glx/Cr、mI/Cr比值,应用独立两样本t检验分析两组间各代谢物浓度差异.病例组按照血清总胆红素(TSB)水平分为342.0 μmol/L513.0 μmol/L 11例共3组,对3组患儿脑内代谢物浓度进行方差分析.结果 病例组中有23例在常规MRI表现为T_1WI苍白球高信号,其余5例常规MRI表现无异常.对照组15名均无异常信号出现.~1H-MRS检查病例组15例单体素成像患儿中,7例mI峰增高,mI/Cr比值为0.74±0.23,对照组为0.57±0.20,两组差异有统计学意义(t=2.13,P=0.04);13例ABE患儿Glx波峰明显增高,Glx/Cr比值单体素为1.45±0.37,多体素为0.51±0.36,对照组为0.95±0.23、0.29±0.18,两组间比较差异具有统计学意义(t值分别为4.40、2.17,P值分别为0.00、0.03).结论 双侧苍白球对称性T_1WI高信号为ABE特征性表现,~1H-MRS可见Glx/Cr、mI/Cr升高,提示相应病理生理变化.     

海洛因依赖者前额叶皮质及杏仁核1H-MR波谱研究

Objective To explore the characteristic findings of 1H-MR spectroscopy(1H-MRS) in the prefrontal cortex and amygdala of patients with heroine dependence(HD), and the relationship to total cumulative dose of inhaled heroine.Methods Fourteen male HD patients and 12 healthy controls (HC) underwent 1H-MRS at the prefrontal cortex and amygdala regions.The total cumulative in haled heroin dose was (852±341) g in HD.Ratios of N-acetylaspartate/creatine(NAA/Cr) and choline/creatine (Cho/Cr) were respectively measured in the prefrontal cortex and bilateral amygdale regions.The student's t test and the linear correlation were employed for statistical analysis.Results Compared to HC group, HD patients had a significant lower ratio of NAA/Cr in the prefrontal cortex (1.44±0.46 vs 1.50±0.75, t=1.77 ,P <0.05), left amygdala region (1.32±0.08 vs 1.42±0.08, t=3.41, P < 0.05), and right amygdala region (1.34±0.09 vs 1.44±0.10, t=2.63, P <0.05), the HD patients had a significant increased ratio of Cho/Cr in the prefrontal cortex (0.92±0.06 vs 0.86±0.08, t=2.31, P < 0.05), left amygdala region (1.20+0.12 vs 1.07±0.04, t=3.60,P<0.05) and right amygdala region(1.26±0.15 vs 1.12±0.11,t=2.60,P <0.05).There was a negative linear correlation between the total cumulative inhaled heroine dose and the ratio of NKA/Cr in the prefrontal cortex (r=-0.9159, P < 0.01), left amygdala region (r=-0.8756, P < 0.01), and right amygdala region (r=-0.9399, P < 0.01) respectively.Conclusions The study indicates that neuronal damage and glial proliferation may occur in the prefrontal cortex and amygdala region, which suggests the abnormalities of executive function and emotion in patients with HD.A relationship exists between the heroin-induced metabolic abnormality and the total cumulative dose of inhaled heroine.     

海洛因依赖者前额叶皮质及杏仁核1H-MR波谱研究

Objective To explore the characteristic findings of 1H-MR spectroscopy(1H-MRS) in the prefrontal cortex and amygdala of patients with heroine dependence(HD), and the relationship to total cumulative dose of inhaled heroine.Methods Fourteen male HD patients and 12 healthy controls (HC) underwent 1H-MRS at the prefrontal cortex and amygdala regions.The total cumulative in haled heroin dose was (852±341) g in HD.Ratios of N-acetylaspartate/creatine(NAA/Cr) and choline/creatine (Cho/Cr) were respectively measured in the prefrontal cortex and bilateral amygdale regions.The student's t test and the linear correlation were employed for statistical analysis.Results Compared to HC group, HD patients had a significant lower ratio of NAA/Cr in the prefrontal cortex (1.44±0.46 vs 1.50±0.75, t=1.77 ,P <0.05), left amygdala region (1.32±0.08 vs 1.42±0.08, t=3.41, P < 0.05), and right amygdala region (1.34±0.09 vs 1.44±0.10, t=2.63, P <0.05), the HD patients had a significant increased ratio of Cho/Cr in the prefrontal cortex (0.92±0.06 vs 0.86±0.08, t=2.31, P < 0.05), left amygdala region (1.20+0.12 vs 1.07±0.04, t=3.60,P<0.05) and right amygdala region(1.26±0.15 vs 1.12±0.11,t=2.60,P <0.05).There was a negative linear correlation between the total cumulative inhaled heroine dose and the ratio of NKA/Cr in the prefrontal cortex (r=-0.9159, P < 0.01), left amygdala region (r=-0.8756, P < 0.01), and right amygdala region (r=-0.9399, P < 0.01) respectively.Conclusions The study indicates that neuronal damage and glial proliferation may occur in the prefrontal cortex and amygdala region, which suggests the abnormalities of executive function and emotion in patients with HD.A relationship exists between the heroin-induced metabolic abnormality and the total cumulative dose of inhaled heroine.     

海洛因依赖者前额叶皮质及杏仁核1H-MR波谱研究

Objective To explore the characteristic findings of 1H-MR spectroscopy(1H-MRS) in the prefrontal cortex and amygdala of patients with heroine dependence(HD), and the relationship to total cumulative dose of inhaled heroine.Methods Fourteen male HD patients and 12 healthy controls (HC) underwent 1H-MRS at the prefrontal cortex and amygdala regions.The total cumulative in haled heroin dose was (852±341) g in HD.Ratios of N-acetylaspartate/creatine(NAA/Cr) and choline/creatine (Cho/Cr) were respectively measured in the prefrontal cortex and bilateral amygdale regions.The student's t test and the linear correlation were employed for statistical analysis.Results Compared to HC group, HD patients had a significant lower ratio of NAA/Cr in the prefrontal cortex (1.44±0.46 vs 1.50±0.75, t=1.77 ,P <0.05), left amygdala region (1.32±0.08 vs 1.42±0.08, t=3.41, P < 0.05), and right amygdala region (1.34±0.09 vs 1.44±0.10, t=2.63, P <0.05), the HD patients had a significant increased ratio of Cho/Cr in the prefrontal cortex (0.92±0.06 vs 0.86±0.08, t=2.31, P < 0.05), left amygdala region (1.20+0.12 vs 1.07±0.04, t=3.60,P<0.05) and right amygdala region(1.26±0.15 vs 1.12±0.11,t=2.60,P <0.05).There was a negative linear correlation between the total cumulative inhaled heroine dose and the ratio of NKA/Cr in the prefrontal cortex (r=-0.9159, P < 0.01), left amygdala region (r=-0.8756, P < 0.01), and right amygdala region (r=-0.9399, P < 0.01) respectively.Conclusions The study indicates that neuronal damage and glial proliferation may occur in the prefrontal cortex and amygdala region, which suggests the abnormalities of executive function and emotion in patients with HD.A relationship exists between the heroin-induced metabolic abnormality and the total cumulative dose of inhaled heroine.     

海洛因依赖者前额叶皮质及杏仁核1H-MR波谱研究

Objective To explore the characteristic findings of 1H-MR spectroscopy(1H-MRS) in the prefrontal cortex and amygdala of patients with heroine dependence(HD), and the relationship to total cumulative dose of inhaled heroine.Methods Fourteen male HD patients and 12 healthy controls (HC) underwent 1H-MRS at the prefrontal cortex and amygdala regions.The total cumulative in haled heroin dose was (852±341) g in HD.Ratios of N-acetylaspartate/creatine(NAA/Cr) and choline/creatine (Cho/Cr) were respectively measured in the prefrontal cortex and bilateral amygdale regions.The student's t test and the linear correlation were employed for statistical analysis.Results Compared to HC group, HD patients had a significant lower ratio of NAA/Cr in the prefrontal cortex (1.44±0.46 vs 1.50±0.75, t=1.77 ,P <0.05), left amygdala region (1.32±0.08 vs 1.42±0.08, t=3.41, P < 0.05), and right amygdala region (1.34±0.09 vs 1.44±0.10, t=2.63, P <0.05), the HD patients had a significant increased ratio of Cho/Cr in the prefrontal cortex (0.92±0.06 vs 0.86±0.08, t=2.31, P < 0.05), left amygdala region (1.20+0.12 vs 1.07±0.04, t=3.60,P<0.05) and right amygdala region(1.26±0.15 vs 1.12±0.11,t=2.60,P <0.05).There was a negative linear correlation between the total cumulative inhaled heroine dose and the ratio of NKA/Cr in the prefrontal cortex (r=-0.9159, P < 0.01), left amygdala region (r=-0.8756, P < 0.01), and right amygdala region (r=-0.9399, P < 0.01) respectively.Conclusions The study indicates that neuronal damage and glial proliferation may occur in the prefrontal cortex and amygdala region, which suggests the abnormalities of executive function and emotion in patients with HD.A relationship exists between the heroin-induced metabolic abnormality and the total cumulative dose of inhaled heroine.     

海洛因依赖者前额叶皮质及杏仁核1H-MR波谱研究

Objective To explore the characteristic findings of 1H-MR spectroscopy(1H-MRS) in the prefrontal cortex and amygdala of patients with heroine dependence(HD), and the relationship to total cumulative dose of inhaled heroine.Methods Fourteen male HD patients and 12 healthy controls (HC) underwent 1H-MRS at the prefrontal cortex and amygdala regions.The total cumulative in haled heroin dose was (852±341) g in HD.Ratios of N-acetylaspartate/creatine(NAA/Cr) and choline/creatine (Cho/Cr) were respectively measured in the prefrontal cortex and bilateral amygdale regions.The student's t test and the linear correlation were employed for statistical analysis.Results Compared to HC group, HD patients had a significant lower ratio of NAA/Cr in the prefrontal cortex (1.44±0.46 vs 1.50±0.75, t=1.77 ,P <0.05), left amygdala region (1.32±0.08 vs 1.42±0.08, t=3.41, P < 0.05), and right amygdala region (1.34±0.09 vs 1.44±0.10, t=2.63, P <0.05), the HD patients had a significant increased ratio of Cho/Cr in the prefrontal cortex (0.92±0.06 vs 0.86±0.08, t=2.31, P < 0.05), left amygdala region (1.20+0.12 vs 1.07±0.04, t=3.60,P<0.05) and right amygdala region(1.26±0.15 vs 1.12±0.11,t=2.60,P <0.05).There was a negative linear correlation between the total cumulative inhaled heroine dose and the ratio of NKA/Cr in the prefrontal cortex (r=-0.9159, P < 0.01), left amygdala region (r=-0.8756, P < 0.01), and right amygdala region (r=-0.9399, P < 0.01) respectively.Conclusions The study indicates that neuronal damage and glial proliferation may occur in the prefrontal cortex and amygdala region, which suggests the abnormalities of executive function and emotion in patients with HD.A relationship exists between the heroin-induced metabolic abnormality and the total cumulative dose of inhaled heroine.     

含软骨基质型肉瘤的MR钆喷替酸葡甲胺增强和扩散加权成像特点

Objective To study the Gadolinium-enhanced MRI and diffusion weighted imaging (DWI) characteristics of the chondroid matrix-forming sarcomas.Methods Contrast-enhanced MRI and DWI were performed in 14 eases of chondroid matrix-forming sarcomas (10 chondrosarcomas,4 chondroblastic esteosarcomas) and 13 cases of other types of osteosarcomas.DWI was obtained with a single-shot echo-planar imaging (EPI) sequence using a 1.5 T MR imager with two different b values of 0 and 700 s/mm2.The apparent diffusion coefficient (ADC) values were obtained in GE Functiontool software.The contrast-enhancement pattern was evaluated and the ADC values of ehondroid matrix-forming sarcomas was compared with that of other types of asteosarcoma.Independent sample t-test was performed to evaluate the difference of ADC values between the group of chondroid matrix-forming sarcoma and the group of other types of osteosarcoma.In addition, nonparametrie test was used to assess the difference of ADC values between the chondrosareoma and the chondroblastic osteosarcoma.P value less than 0.05 was considered to represent a statistical significance.Results For 14 eases of ehondroid matrix-forming sarcomas, peripheral enhancement was found in all cases, septonodular enhancement was identified in 12 cases.While 13 eases of other types of osteosarcowas demonstrated heterogeneous enhancement.The mean ADC value of chondroid matrix-forming sarcomas [(2.56 ±0.35) × 10 -3 mm2/s] was significantly higher than that of other types of osteosarcoma [( 1.16±0.20) × 10-3 mm2/s] (t = 12.704,P <0.O1 ).There was no significant difference in the ADC value between the chondrosarcoma and the chondroblastie osteesarcama(Z =0.507 ,P =0.959).Conclusion Contrast-enhanced MRI and DWI can improve differentiation between chondroid matrix-forming sarcomas and other types of osteosarcomas.     

含软骨基质型肉瘤的MR钆喷替酸葡甲胺增强和扩散加权成像特点

Objective To study the Gadolinium-enhanced MRI and diffusion weighted imaging (DWI) characteristics of the chondroid matrix-forming sarcomas.Methods Contrast-enhanced MRI and DWI were performed in 14 eases of chondroid matrix-forming sarcomas (10 chondrosarcomas,4 chondroblastic esteosarcomas) and 13 cases of other types of osteosarcomas.DWI was obtained with a single-shot echo-planar imaging (EPI) sequence using a 1.5 T MR imager with two different b values of 0 and 700 s/mm2.The apparent diffusion coefficient (ADC) values were obtained in GE Functiontool software.The contrast-enhancement pattern was evaluated and the ADC values of ehondroid matrix-forming sarcomas was compared with that of other types of asteosarcoma.Independent sample t-test was performed to evaluate the difference of ADC values between the group of chondroid matrix-forming sarcoma and the group of other types of osteosarcoma.In addition, nonparametrie test was used to assess the difference of ADC values between the chondrosareoma and the chondroblastic osteosarcoma.P value less than 0.05 was considered to represent a statistical significance.Results For 14 eases of ehondroid matrix-forming sarcomas, peripheral enhancement was found in all cases, septonodular enhancement was identified in 12 cases.While 13 eases of other types of osteosarcowas demonstrated heterogeneous enhancement.The mean ADC value of chondroid matrix-forming sarcomas [(2.56 ±0.35) × 10 -3 mm2/s] was significantly higher than that of other types of osteosarcoma [( 1.16±0.20) × 10-3 mm2/s] (t = 12.704,P <0.O1 ).There was no significant difference in the ADC value between the chondrosarcoma and the chondroblastie osteesarcama(Z =0.507 ,P =0.959).Conclusion Contrast-enhanced MRI and DWI can improve differentiation between chondroid matrix-forming sarcomas and other types of osteosarcomas.     

Management of breast magnetic resonance imaging-detected lesions

Breast magnetic resonance imaging (MRI) has become an essential component of breast imaging. Whether it is used as a problem-solving tool or a screening test or for staging patients with breast cancer, it detects many lesions in the breast. The challenge for the radiologist is to distinguish significant from insignificant lesions and to direct their management. A brief summary of the terminology according to the American College of Radiologists lexicon will be provided. This review article will cover the differential diagnosis of enhancing lesions, including masses and nonmass enhancement, from benign and malignant causes. Some of the specific morphologic and kinetic features that help to differentiate benign from malignant lesions will be illustrated, and positive predictive values of these features will be reviewed. The various methods of investigating enhancing lesions of the breast will be discussed, including second-look ultrasound, ultrasound-guided biopsy, stereotactic biopsy, and MRI-guided biopsy. A practical approach to the management of MRI-detected lesions will include timing of follow-up, when to biopsy and when to ignore enhancing lesions in the breast.     

自闭症的常规MRI和1H-MRS表现

目的 探讨常规MR成像和1H MR波谱(MRS)在自闭症诊断中的价值.资料与方法 回顾性分析12例自闭症患者的全脑常规MR扫描及其中8例患者额叶和海马的多体素2D 1H MR波谱扫描表现.结果 常规MR扫描发现3例患者的顶叶白质在FLAIR上出现斑片状高信号.1H MRS分析发现5例患者额叶的NAA/Cho明显下降(NAA/Cho<1),其中1例患者的左侧额叶出现Lac峰;另外有2例患者海马的NAA/Cho出现下降(NAA/Cho<1).结论 常规MR成像和1H MRS可发现部分自闭症患者脑组织异常.     

Biomedical implants and devices: assessment of magnetic field interactions with a 3.0-Tesla MR system

PURPOSE: To evaluate magnetic field interactions for 109 different biomedical implants and devices in association with exposure to a 3.0-Tesla magnetic resonance (MR) system. MATERIALS AND METHODS: A total of 109 implants and devices (aneurysm clips, 32; clips, fasteners, and staples, 10; coils and stents, 10; heart valve prostheses and annuloplasty rings, 12; orthopedic implants, five; suture materials, 13; vascular access ports and accessories, 13; miscellaneous implants and devices, 14) were tested for magnetic field interactions at 3.0-Tesla using previously-described, standardized techniques to assess magnetic field translational attraction and torque. RESULTS: The deflection angles and torque measurements ranged, respectively, from 0 to 16 degrees and 0 to +2 for the aneurysm clips; 0 to 90 degrees and 0 to +4 for the clips, fasteners, and staples; 0 to 47 degrees and 0 to +4 for the coils and stents; 0 to 4 degrees and 0 to +1 for the heart valve prostheses and annuloplasty rings; 0 to 12 degrees and 0 to +2 for the orthopedic implants; 0 to 13 degrees and 0 to +2 for the suture materials; 0 to 52 degrees and 0 to +4 for the vascular access ports and accessories; and 0 to 28 degrees and 0 to +3 for the miscellaneous implants and devices. CONCLUSION: Of the 109 implants and devices assessed for magnetic field interactions at 3.0-Tesla, four (4%) are potentially unsafe based on deflection angle criteria. The implications of these results for patients undergoing MR procedures at 3.0-Tesla is discussed. Notably, these results are specific to the 3.0-Tesla MR system used for this evaluation.     

线粒体脑肌病综合影像表现

目的:探讨多种影像技术对线粒体脑肌病(ME)的诊断价值.方法:回顾性分析7例线粒体脑肌病患者的影像资料,其中7例行常规MRI扫描,3例行MRA扫描,4例行MRS扫描,1例行DSA检查,6例行CT平扫.结果:6例病变主要累及两侧大脑皮层和皮层下,1例主要表现为白质内改变,均表现为长T1、长T2改变;MRA示2例未见明显改变,1例示病变处血管分支明显增粗;4例MRS在病变处检出乳酸双峰,1例在脑脊液中检出乳酸双峰.1例行DSA检查示病灶内血管分支增粗,血运加快.6例行CT检查病灶均呈低密度改变.结论:影像检查尤其是MRI检查对ME的诊断提供了丰富的信息,当年青患者出现非典型性脑梗死表现,MRS检出乳酸双峰时要考虑到线粒体脑肌病的可能.     

三维MR增强扫描在多发脑转移瘤诊断中的价值

目的 探讨三维MR增强扫描(3DE MR)在诊断多发性脑转移瘤(BM)中的价值.方法 筛选临床拟诊为BM患者64例行MR平扫及增强检查,增强扫描包括2DE MR和3DE MR两种扫描方式,根据3DE MR的图像特征及临床病史,选取有多发BM病灶的患者35例.对两种不同增强扫描方式图像质量进行分析,并在显示病灶数目、大小方面进行比较.结果 (1)图像质量.3DE MR图像上平均病灶与脑白质比值(LBR)为1.43±0.33,平均信噪比(SNR)为21.98±10.1,平均对比噪声比(CNR)7.72 ±4.45,2DE MR图像上平均LBR为1.21±0.22,平均SNR为30.52±11.28,平均CNR为6.63 ±4.60,利用配对资料t检验对两种扫描方式所得图像的参数进行统计学分析,得出LBR和SNR两个指标在两种扫描方式间有差异,CNR在两种扫描方式间无差异.(2)病灶数目比较.在35例BM患者中3DE MR较2DE MR多发现121个病灶,平均每例多发现3.4个病灶.(3)病灶大小比较.本组病例中,以2DE MR扫描方式中所发现的336个病灶为准,测量对应病灶在不同扫描方式中的大小,在2DEMR中所测病灶平均大小为(8.87±0.42)mm,3DE MR中平均大小为(9.76 ±0.43) mm,利用配对资料的t检验对两种扫描方式所测得病灶大小进行统计学分析,所有病灶在两种扫描方式中所测大小存在差异.结论 3DE MR较常规2DE MR发现BM更敏感,在显示病灶数目、大小方面明显优于2DE MR,可明显降低2DE MR扫描方式的漏诊率及误诊率,应成为临床BM常规增强扫描方式.     

烟雾病的磁共振成像诊断

目的：回顾分析８例烟雾病的磁共振成像表现，探讨磁共振成像对烟雾病的诊断价值。方法：８例烟雾病中男女各４例。年龄４～４９岁，平均２０．４岁。磁共振成像应用Ｓｉｅｍｅｎｓ１．０ＴＭＲ系统和头表面线圈。均有ＳＥ序列Ｔ１ＷＩ和Ｔ２ＷＩ，７例有三维时间飞跃法磁共振血管造影（３Ｄ－ＴＯＦＭＲＡ），１例有ＤＳＡ。结果：ＳＥ序列ＭＲＩ均见丘脑－基底节区（单侧２例，双侧６例）有扩张的烟雾血管，其中以Ｔ１ＷＩ显示更为清楚直观。７例３Ｄ－ＴＯＦＭＲＡ和１例ＤＳＡ均见ＩＣＡ上端、ＭＣＡ和ＡＣＡ近端闭塞以及丘脑－基底节区的烟雾血管。这些病理血管分布侧别与ＳＥ序列磁共振成像所见一致。结论：ＳＥ序列磁共振成像和３Ｄ－ＴＯＦＭＲＡ是诊断烟雾病的有效方法。Ｔ１ＷＩ显示丘脑－基底节区烟雾血管优于Ｔ２ＷＩ。３Ｄ－ＴＯＦＭＲＡ尚适用于烟雾病血管旁路术后随诊及其高危人群普查。