3.0T 1H-MRS在颅内常见肿瘤中的应用研究

目的 探讨3.0 T氢质子磁共振波谱(1H-MRS)对颅内常见肿瘤诊断、鉴别诊断、评价治疗效果及在胶质瘤分级中的价值.资料与方法选取经手术病理或临床确诊的69例颅内肿瘤患者.采用GE Signa EXCITE HD3.0T超导型MR扫描仪对所有患者行颅脑常规MRI扫描和二维多体素序列扫描.采用Functool软件包后处理,分别测定病变实质、病变周围及健侧相应区域的胆碱(Cho)/肌酸(Cr)、Cho/N-乙酰天门冬氨酸(NAA)、NAA/Cr比值及肌醇(MI)值的变化,并对结果进行统计学分析.结果 (1)实质区:低级别胶质瘤的Cho/Cr值与高级别胶质瘤、转移瘤及脑膜瘤间差异有统计学意义(P＜0.01);低级别胶质瘤与高级别胶质瘤、脑膜瘤的Cho/NAA比值分别比较有统计学意义(P＜0.05),转移瘤与高级别胶质瘤、脑膜瘤的Cho/NAA比值分别比较有统计学意义(P＜0.05);低级别胶质瘤NAA/Cr比值与高级别胶质瘤、转移瘤分别比较有统计学意义(P＜0.05),转移瘤与脑膜瘤比较有统计学意义(P＜0.05);低级别胶质瘤的MI值与高级别胶质瘤、转移瘤及脑膜瘤分别比较有统计学意义(P＜0.05).(2)瘤周水肿区:高级别胶质瘤Cho/Cr比值与另外三者比较差异有统计学意义(P＜0.05),低级别胶质瘤Cho/Cr比值与转移瘤、脑膜瘤分别比较差异有统计学意义(P＜0.01);低级别胶质瘤Cho/NAA比值与转移瘤、脑膜瘤分别比较差异有统计学意义(P＜0.05),高级别胶质瘤与转移瘤、脑膜瘤分别比较有统计学意义;低级别胶质瘤与高级别胶质瘤NAA/Cr比值差异有统计学意义(P＜0.05);各肿瘤瘤周水肿区MI值比较无统计学意义(P＞0.05).结论 1H-MRS在鉴别诊断颅内肿瘤中有重要价值,可较准确显示肿瘤瘤周浸润情况,结合其他影像征象对胶质瘤分级诊断亦有重要价值.     

3．0T磁共振多体素^1H-MRS和DWI对常见脑肿瘤特征分析的价值

目的：探讨3．0T磁共振多体素^1H-MRS及DWI在常见颅内肿瘤特征分析的价值。方法：脑肿瘤患者30例,多体素^1H-MRS感兴趣区包括肿瘤实质区、瘤周水肿区及正常参照区。计算上述各区域的NAA、Cho、Cr等多种代谢物的值;DWI测量肿瘤不同部位信号值,计算ADC值。结果：胶质瘤、转移瘤、脑膜瘤三者之间肿瘤实质区的NAA／Cho、NAA／Cr和Cho／Cr平均值与参照区比较有显著性差异（P〈0．05）;高、低级别胶质瘤间瘤周水肿区的NAA／Cho和Cho／Cr具有统计学差异（P〈0．05）,高级别胶质瘤与转移瘤间瘤周水肿区的NAA／Cho、NAA／Cr和Cho／Cr均有统计学差异（P〈0．05）。DWI示高、低级别胶质瘤间肿瘤实质区及瘤周水肿区的ADC值均有显著性差异（P〈0．05）;高级别胶质瘤与转移瘤间瘤周水肿区的ADC值有统计学差异（P〈0．05）。结论：多体素^1H-MRS与DWI相结合有助于脑肿瘤的特征分析、胶质瘤恶性程度分级、确定病灶浸润范围等。     

脑肿瘤瘤周水肿MSCT灌注成像的定量研究

目的：探讨脑肿瘤瘤周水肿的MSCT灌注特点及其在脑肿瘤诊断与鉴别诊断中的临床应用价值。方法：对58例脑肿瘤（胶质瘤20例,转移瘤17例,脑膜瘤21例）患者进行常规CT扫描和CT灌注扫描。瘤周水肿区分为近侧和远侧两个部分,对照分析近侧、远侧水肿区以及正常脑组织的CT灌注参数的差异及相关性。结果：高级别胶质瘤、恶性脑膜瘤的近侧瘤周水肿区的CBF、CBV、PS值高于低级别胶质瘤、转移瘤、脑膜瘤的近侧瘤周水肿区（P〈0.05）;各种脑肿瘤近侧瘤周水肿区的CBF、CBV值明显低于对侧相应部位脑白质的CBF、CBV值,其间差异有统计学意义（P〈0.05）。高级别胶质瘤、恶性脑膜瘤近侧瘤周水肿区的PS值高于对侧相应部位脑白质的PS值,其间差异有统计学意义（P〈0.05）。低级别胶质瘤、转移瘤、良性脑膜瘤近侧瘤周水肿区与对侧相应部位脑白质的PS值比较差异无统计学意义（P〉0.05）。结论：近侧瘤周水肿区的灌注参数有助于准确评价脑肿瘤瘤周水肿区的血流动力学改变及良恶性脑肿瘤的鉴别。     

脑胶质瘤周围区的^1H-MRS研究

目的应用多体素氢质子磁共振波谱(1H-MRS)探讨胶质瘤周围区脑代谢改变的特点,评价多体素1H-MRS在胶质瘤周围区的应用价值.方法23例病理证实的脑胶质瘤病人分为低级别组(WHO Ⅰ～Ⅱ级)13例和高级别组(WHOⅢ～Ⅳ级)10例.所有病例术前均行多体素1H-MRS检查,测量肿瘤实质区、周围区及对侧正常脑组织区代谢产物的相对定量,进行统计学比较.结果多体素1H-MRS显示高级别胶质瘤的周围区与实质区NAA/Cr、Cho/Cr、NAA/Cho值差异有统计学意义(P值均为0.00).高级别胶质瘤周围区与对侧正常脑组织区NAA/Cr、Cho/Cr、NAA/Cho、Glx/Cr值差异均有统计学意义(P值均为0.00);低级别胶质瘤周围区与实质区NAA/Cr、Cho/Cr、NAA/Cho值差异均有统计学意义(P值均为0.00);低级别胶质瘤周围区与对侧正常脑组织区Cho/Cr、NAA/Cho值差异均有统计学意义(P值分别为0.02、0.00);高级别与低级别胶质瘤实质区NAA/Cr、NAA/Cho、Cho/Cr、Glx/Cr值差异均有统计学意义(P值分别为0.00、0.00、0.03、0.00);高级别与低级别胶质瘤周嗣区NAA/Cr、NAA/Cho、Cho/Cr、Glx/Cr值差异均有统计学意义(P值均为0.00).结论脑胶质瘤周围区代谢物的改变反映了肿瘤向瘤周组织浸润,对确定胶质瘤的分级及预测侵袭性病变的浸润范围有帮助.     

氢质子磁共振波谱鉴别孤立脑转移瘤与高级别脑胶质瘤的临床应用价值

目的探讨孤立脑转移瘤与高级别脑胶质瘤的MRI、1H-MRS的临床应用价值。方法经手术病理证实的高级别脑胶质瘤(Ⅲ、Ⅳ级脑胶质瘤)25例及孤立脑转移瘤20例,术前均行常规MRI及1H-MRS检查。从病变部位、信号强度、水肿程度、强化形态及出血与否等方面评价孤立脑转移瘤和高级别脑胶质瘤的常规MRI表现;检测肿瘤组织、瘤周组织区和对侧正常脑组织对照区NAA、Cho和Cr的变化,计算出NAA/Cho、NAA/Cr和Cho/Cr的比值。结果(1)孤立脑转移瘤和高级别脑胶质瘤的常规MRI各种表现中仅病变部位和水肿程度在两者间存在差别,P值分别为0.009、0.046;(2)高级别脑胶质瘤和孤立脑转移瘤的肿瘤组织的NAA/Cr和NAA/Cho比值存在显著性差异(P<0.01),但Cho/Cr比值无显著性差异(P>0.05);(3)高级别脑胶质瘤和孤立脑转移瘤的瘤周组织的Cho/Cr比值存在显著性差异(P<0.05),但NAA/Cr和NAA/Cho比值无显著性差异(P>0.05)。结论常规MRI结合1H-MRS表现可望提高鉴别高级别脑胶质瘤和孤立脑转移瘤的可能性。     

脑胶质瘤周围区的~1H-MRS研究

目的应用多体素氢质子磁共振波谱(1H-MRS)探讨胶质瘤周围区脑代谢改变的特点,评价多体素1H-MRS在胶质瘤周围区的应用价值。方法23例病理证实的脑胶质瘤病人分为低级别组(WHOⅠ～Ⅱ级)13例和高级别组(WHOⅢ～Ⅳ级)10例,所有病例术前均行多体素1H-MRS检查,测量肿瘤实质区、周围区及对侧正常脑组织区代谢产物的相对定量,进行统计学比较。结果多体素1H-MRS显示高级别胶质瘤的周围区与实质区NAA/Cr、Cho/Cr、NAA/Cho值差异有统计学意义(P值均为0.00)。高级别胶质瘤周围区与对侧正常脑组织区NAA/Cr、Cho/Cr、NAA/Cho、Glx/Cr值差异均有统计学意义(P值均为0.00);低级别胶质瘤周围区与实质区NAA/Cr、Cho/Cr、NAA/Cho值差异均有统计学意义(P值均为0.00);低级别胶质瘤周围区与对侧正常脑组织区Cho/Cr、NAA/Cho值差异均有统计学意义(P值分别为0.02、0.00);高级别与低级别胶质瘤实质区NAA/Cr、NAA/Cho、Cho/Cr、Glx/Cr值差异均有统计学意义(P值分别为0.00、0.00、0.03、0.00);高级别与低级别胶质瘤周...     

1H-MRS分析在颅脑肿瘤研究中的临床应用价值

目的研究脑肿瘤1H-MRS的不同表现及临床应用价值.方法80例行1H-MRS检查并经病理证实或临床追踪证实的脑肿瘤患者,取对侧正常部位对照30例.采用激励法进行单体素波谱采集或二维波谱成像,对有显著性差异的代谢物比值均数比较.结果与对照组相比,脑肿瘤NAA均有不同程度的下降,脑外肿瘤低于脑内肿瘤,高级别(Ⅲ一Ⅳ)胶质瘤较低级者(Ⅰ～Ⅱ)下降明显.Cho/Cr升高,高级胶质瘤比低级胶质瘤高(P＜0.05),高级别胶质瘤及转移瘤瘤体瘤周水肿区Cho/Cr有显著性差异.部分高级别胶质瘤及转移瘤可检测到Lac、Lip峰.部分脑膜瘤(4/19)可检测到Ala峰.结论1H-MRS从微观水平分析脑肿瘤代谢信息的无创性方法,对脑肿瘤的诊断、鉴别诊断及疗效评估、术后复发、组织上分级有重要帮助.     

二维化学位移1H-MRS对胶质瘤级别划分的价值

目的:探讨二维化学位移氢质子磁共振波谱(2DCSI1H-MRS)对不同级别胶质瘤划分的价值。方法:回顾性分析经临床诊断和(或)经手术病理证实的75例患者的MRI及MRS表现,包括Ⅱ级胶质瘤30例,Ⅲ级胶质瘤25例,Ⅳ级胶质瘤20例,计算瘤体区、瘤周水肿区及正常脑组织的胆碱(choline,Cho)、肌酸(creatine,Cr)、N-乙酰天门氡氨酸(N-acetyl aspartate,NAA)的浓度及Cho/Cr、NAA/Cr、NAA/Cho的比值。结果:①Ⅱ、Ⅲ、Ⅳ级胶质瘤瘤体区的Cho/Cr分别为1.62±0.42、2.46±1.82、3.03±1.51,瘤水肿周区的Cho/Cr分别为0.86±0.45、1.36±0.74、1.76±0.64,差异均有统计学意义(P<0.05);②与对侧正常脑组织比较,在瘤体区三组胶质瘤各值均有差异,在瘤周水肿区Ⅱ级胶质瘤Cho、NAA有差异,Ⅲ、Ⅳ级胶质瘤各值均有差异;③当取瘤体区Cho/Cr>2,瘤周区Cho/Cr>1时,鉴别高级别(Ⅲ、Ⅳ级)胶质瘤的敏感度、特异度、阳性预测值、阴性预测值分别为80.9%、70.1%、87.9%、60.1%和83.5%、74.2%、88.5%、73.6%;④当MRI与MRS联合使用时,鉴别高低级胶质瘤的敏感度、特异度、PPV、NPV均较单独采用其中一种方法时提高。结论:2DCSI1H-MRS可以有效鉴别不同级别胶质瘤,MRI与MRS联合使用时临床价值更高。     

2D CSI1H-MRS对不同类别脑肿瘤的鉴别诊断

目的 探讨二维化学位移氢质子磁共振波谱(2D CSI1H-MRS)对胶质瘤、转移瘤、脑膜瘤的鉴别诊断价值.资料与方法 回顾性分析经临床诊断或经手术病理证实的90例患者的MRI及MRS资料,包括胶质瘤45例,转移瘤23例,脑膜瘤22例.计算瘤体及瘤周水肿区的Cho、Cr、NAA的浓度及Cho/Cr、NAA/Cr、NAA/Cho的比值.结果 (1)胶质瘤、转移瘤、脑膜瘤瘤体区的NAA/Cho分别为0.41±0.19、0.56±0.15、0.15±0.07,三组差异均有统计学意义(P＜0.05);(2)胶质瘤、转移瘤、脑膜瘤瘤周水肿区的Cho浓度分别为0.40 ±0.16、0.26±0.09、0.13±0.07,3组差异均有显著统计学意义(P＜0.01),胶质瘤显著高于其他两者,当取Cho＞0.45时,MRS区分胶质瘤的特异性、敏感性、阳性预测值、阴性预测值分别为83%、94%、77.3%、85.7%.结论 2D CSI1H-MRS对胶质瘤、转移瘤、脑膜瘤的鉴别诊断有重要意义.     

多体素1H - MRS在脑肿瘤强化周围区域中的临床应用

目的探讨多体素1H磁共振波谱(1H-MRS)在颅脑肿瘤强化周围区的代谢物改变特点及其鉴别诊断意义。方法脑肿瘤患者35例,多体素1H-MRS采集NAA、Cho、Cr、Lac、L ip、m I和A la峰,分别计算星形细胞瘤、转移瘤、脑膜瘤的肿瘤强化区、强化周围区和正常参照区域的代谢物浓度,计算不同脑肿瘤、同种脑肿瘤不同区域及高、低级胶质瘤各代谢物比值平均值,比较统计学差异,记录Lac、L ip、m I和A la是否出现。结果肿瘤强化区NAA/Cho、NAA/Cr和Cho/Cr平均值与正常参照区比较均有显著性差异(P<0.05);共出现17例Lac峰、7例L ip峰、6例A la峰和6例m I峰;强化周围区,三者的NAA/Cho、NAA/Cr、NAA/nCr、Cho/NAA值具显著性差异;良、恶性胶质瘤间,NAA/Cho、NAA/nCr、Cho/Cr和Cho/nCho值具有统计学差异(P<0.05)。结论多体素1H-MRS对肿瘤强化周围区域的评价,有助于星形细胞瘤与脑转移瘤、脑膜瘤的鉴别诊断及浸润范围的划定。     

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.     

急性胆红素脑病常规MRI及1H-MR波谱表现

Objective To investigate the characterized imaging in conventional MRI, get information about the metabolites in basal ganglia from proton MR Spectroscopy(1H-MRS) of acute bilirubin encephalopathy(ABE) and find out the relationship between those changes and bilirubin levels. Methods Twenty-eight patients with acute bilirubin encephalopathy and 15 normal neonates underwent MR and 1H-MRS examinations T1 WI, T2WI and DWI were collected via conventional MRI scanning of all neonates. All patients underwent multi-voxels scanning and 15 of them had single voxel scanning. 1H-MRS used point resolved spectroscopy (PRESS) both in multi-voxels and single voxel scanning. The data of them were acquired from the ROIs placed in basal ganglia and globus pallidus, respectively. The metabolites including NAA choline, Lactate, glutamate and glutamine, myoinositol and creatine were quantitatively analyzed to compare them between the control group and the case group. Equality of variance between patient data and normal values were tested by using the two-tailed t test. The case group was divided into three groups of 342.0 μmol/L < TSB ≤ 427. 5 μmol/L,427.5 μmol/L < TSB ≤ 513.0 μmol/L, TSB > 513.0 μmol/L including 8,9,11 patients, respectively. Analysis of variance was used for statistics. Results Conventional magnetic resonance imaging showed symmetrical high signal of T1WI in globus pallidus of 23 patients. The case group and the control group were significantly different. Single voxel 1H-MRS revealed that the relative concentrations of Glx/Gr and mI/Cr in the control group were 0.95±0.23, 0.57±0.20, respectively, While those in case group were 1.45±0.37, 0.74±0.23, respectively. There were significant differences between two groups (t =2. 13,4. 40,P =0.04,0.00 respectively). Multi-voxels scanning 1H-MRS revealed that Glx / Cr were 0.51±0.36 in case group and 0.29±0.18 in control group. There was also a significant difference between two groups (t =2.17,P =0.03). And the values of Cho/Cr, NAA/Cr and Lac/Cr were not significantly different. The results were same in multi-voxels 1H-MRS. Total bilirubin level and the concentration of metabolites in the brain do not have obvious correlation. Conclusions ABE has a characteristic signature which is symmetrical high signal of T1 WI in globus pallidus on conventional MBI; The values of mI/Cr and Glx/Cr remarkably increase as detected by 1H-MRS, which is generally in agreement with what has been known about bilirubin pathology.     

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.     

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.     

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.     

烟雾病的MRI、MRA诊断价值

 目的探讨MRI、MRA对烟雾病(Moyamoya病)的诊断价值.方法对11例Moyamoya病患者行MRI和MRA检查,MRI包括横轴位和矢状位T1WI、T2WI、FLAIR;MRA采用3D TOF法,3例行增强MRA.结果MRI表现为:(1)Moyamoya血管:双侧3例,单侧8例;(2)脑梗死和脑软化灶11例;(3)局部脑萎缩3例.MRA表现为3例双侧颈内动脉狭窄,双侧大脑中、前动脉闭塞,大脑后动脉形成异常血管网;6例右侧颈内动脉、大脑中动脉狭窄;2例左侧颈内动脉、大脑中动脉狭窄.结论MRI能良好的显示脑内病变,MRA能较完整的显示异常血管,MRI与MRA相结合可作为烟雾病诊断的首选检查方法.