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.     

MRI及MRS对新生儿急性胆红素脑病的诊断效能比较

目的:探讨MRI及MRS对新生儿急性胆红素脑病的诊断效能,并进行比较。方法:回顾性分析我院收治的高胆红素血症患儿198例的临床资料,依据是否发生急性胆红素脑病分为脑病组和危险组,同期选取健康新生儿30例作为对照组。所有研究对象均行MRI及MRS分析N-乙酰天门冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr),并以临床诊断为对照,统计分析MRI及MRS结果。结果:MRI示急性胆红素脑病患儿苍白球区主要以T_1WI呈高信号为特征,T_2WI呈等或高信号;DWI未见特殊变化(均呈等信号);MRS示急性胆红素脑病患儿可见Cho峰、NAA峰及Cr峰,但NAA峰普遍较低,部分患儿NAA峰明显低于Cr峰。ROC曲线显示,MRI诊断新生儿急性胆红素脑病的敏感度、特异度、准确度分别为84.33%、88.28%、86.84%,分别低于MRS的93.98%、95.17%、94.74%(均P0.05)。结论:MRI及MRS对诊断新生儿急性胆红素脑病均有良好的敏感度、特异度和准确度,但MRS诊断效能更高,有利于为临床早期干预提供更可靠证据。     

新生儿胆红素脑病MRI特征的研究

目的 探讨新生儿胆红素脑病(NBE)MRI特征.方法 回顾性分析17例NBE患儿的常规MRI和临床资料,评价苍白球及底丘脑信号高低,并根据底丘脑有无高信号分为底丘脑高信号组和无高信号组,对苍白球信号强度的增加值与血清总胆红素的峰值进行Pearson相关性分析,采用t检验比较底丘脑高信号组和无高信号组血清总胆红素峰值水平.结果 17例患儿中15例有T1 WI苍白球对称性高信号,1例表现为T1 WI苍白球后部对称性高信号.9例患儿底丘脑T1 WI呈高信号,T2 WI呈等信号,主要表现为底丘脑点状或八字形对称性短T1信号.4例患儿中脑、桥脑背侧、延髓T1 WI呈高信号,而桥脑腹侧信号正常.使用1.0 T MR仪扫描的12例患儿苍白球信号强度增加值为249.0～423.8,血清总胆红素峰值为366.0～983.3μmol/L,两者呈正相关(r=0.676,P＜0.05).底丘脑高信号组9例,无高信号组8例,血清总胆红素分别为(660.7±192.4)、(513.3±1cr7.5)μmol/L,2组差异无统计学意义(t=1.914,P＞0.05).结论 NBE的MRI表现有一定特征性,有助于NBE的诊断.     

MRI在新生儿急性胆红素脑病诊断中的价值

目的:探讨T1WI信号强度在新生儿急性胆红素脑病诊断中的价值。方法:对59例皮肤黄染新生儿行颅脑MRI检查,根据血总胆红素水平分为组Ⅰ、Ⅱ、Ⅲ、Ⅳ,测量并比较4组间双侧苍白球T1WI、T2WI信号强度。结果:①肉眼观察,组Ⅳ中6例患儿左、右侧苍白球T1WI信号明显升高,T2WI信号强度无明显差异。②经统计学分析,各组左、右侧苍白球T1WI信号强度差异无统计学意义(P>0.05),组Ⅳ双侧苍白球T1WI信号强度测量值较其余各组明显增高(P<0.05);组Ⅲ双侧苍白球T1WI信号强度测量值较组Ⅰ、Ⅱ明显增高(P<0.05);组Ⅰ、组Ⅱ之间差异无统计学意义(P>0.05)。4组间苍白球T2WI信号强度、eADC、ADC值差异无统计学意义(P>0.05)。结论:苍白球T1WI对称性信号增高是新生儿急性胆红素脑病的重要特征,并与血清胆红素水平密切相关。     

家犬脑挫裂伤1H-MR波谱研究

目的 探讨家犬脑挫裂伤MR波谱(MRS)表现及其应用价值.方法 家犬10只,200 g砝码1.3 m高以自由坠落方式复制脑挫裂伤动物模型,分6个时间点(1 h、24h、72 h、5 d、8 d和14 d)行常规MR及MRS检查.各时段检查结束后处死家犬,取挫裂伤处脑组织行病理检查.结果 伤后1～24h,N-乙酰天冬胺酸/肌酸(NAA/Cr)、胆碱类化合物(Cho)/Cr及NAA/Cho下降,NAA/Cr分别为0.843±0.214,0.862±0.204,对侧 1.069±0.284,1.048±0.232,t=-7.227,-6.718;Cho/Cr1.181±0.224,1.243±0.134,对侧 1.415±0.305,1.455±0.159,t=-4.332,-4.489;NAA/Cho0.701±0.147,0.536±0.136,对侧 0.832±0.245,0.613±0.165,t=-2.652,-2.665(P值均＜0.05);病理示挫伤处见局部点状出血、灶性坏死、神经轴突肿胀、小胶质细胞轻度增生.伤后72 h至5 d,NAA/Cr开始升高,Cho/Cr于5 d时为1.517±0.197,高于对侧,对侧为1.387±0.214(t=3.758,P＜0.05);镜下示炎性细胞浸润明显,血管周围炎、肉芽及纤维瘢痕形成.伤后8～14 d,NAA/Cr与对侧相比差异无统计学意义(0.895±0.105,0.875±0.153,对侧0.989±0.169,0.990±0.173,t=-2.909,-2.471;P值均＞0.05),Cho/Cr高于对侧(1.457±0.168,1.572±0.374,对侧1.334±0.174,1.366 ±0.352,t=7.312,3.201;P值均＜0.05);病理示炎性反应及胶质增生更加显著,14 d时肉芽肿形成.各时段均未见异常乳酸峰及脂质峰.结论 MRS能无创性检测脑挫裂伤后神经元受损及修复情况,了解其脑组织生化代谢改变,反映损伤的程度,为早期治疗和预后的评价提供理论依据.     

新生儿胆红素脑病脑损伤的MRI诊断价值

目的 :探讨新生儿胆红素脑病(NBE)脑损伤的MRI诊断及应用价值。方法 :回顾性分析45例NBE患儿头部MRI表现及临床资料。结果:45例中33例颅脑MRI表现为双侧苍白球区对称性T1WI高信号,17例T1WI高信号同时累及底丘脑或丘脑腹外侧;T2WI均呈等信号,T2FLAIR呈等或稍高信号;DWI均未见明显异常信号改变。12例1~3个月随访复查颅脑MRI,4例T2WI呈对称性稍高信号,临床上有脑损伤后遗症改变;8例颅脑MRI检查未见明显异常,临床上也未见明显神经异常症状。结论:新生儿NBE颅脑MRI苍白球区有特征性表现,即急性期为苍白球对称性T1WI高信号,慢性期为对称性T2WI稍高信号,可为临床早期诊断及预后判断提供帮助。     

新生儿胆红素脑病早期诊断MRI研究

【摘要】暴露于高水平胆红素下可致四肢运动障碍和脑瘫甚至死亡,然而目前对新生儿胆红素脑病（neonatal bilirubin encephalopathy,NBE）早期诊断尚缺乏特异性指标。近年来,诸多学者利用多模态MRI及影像组学开展大量研究,试图为NBE的早期诊断和监测提供新的影像学标志。     

新生儿胆红素脑病的MRI表现

目的 探讨磁共振成像(MRI)对新生儿胆红素脑病(NBE)诊断的价值.方法 回顾性分析28例胆红素脑病新生儿的常规MRI表现和临床资料.结果 28例患儿中27例T1WI苍白球对称性高信号.19例患儿底丘脑T1WI呈高信号,T2WI呈等信号,主要表现为底丘脑点状或"八"字形对称性短T1WI信号.8例患儿中脑、桥脑背侧、延髓T1WI呈高信号,而桥脑腹侧信号正常.扩散加权成像(DWI)显示所有胆红素脑病患儿的基底节无异常信号.结论 常规MRI及DWI有助于新生儿胆红素脑病的诊断.     

鼻咽癌放疗后放射性脑病的1H-MR波谱研究

目的　探讨鼻咽癌放疗后放射性脑病的磁共振氢波谱 (1H MRS)表现 ,了解N 乙酰天门冬氨酸 (NAA)、肌酸 (Cr)和胆碱 (Cho)这 3种物质的代谢规律 ,为放射性脑病的早期诊断提供方法。方法　对照组 10例健康志愿者 ,病例组 2 1例病理诊断为鼻咽癌并进行根治性放疗后经症状及影像学诊断为放射性脑病的病人 ,用化学位移成像法 (CSI)行1H MRS检查。观察各像素中NAA、Cr和Cho的含量、代谢图及它们之间比例。结果　放射性脑病MRI可见病灶中的液化坏死区 3种物质含量基本为零 ,代谢图中无信号 ;可见病灶中非液化坏死区NAA轻度升高 ,Cr和Cho明显降低或为零 ,NAA代谢图呈高信号 ,Cr和Cho低信号 ;可见病灶周边存在 1个区域性的NAA降低、Cr和Cho升高 ,NAA/Cr和NAA/Cho <1,代谢图中信号区分不明显 ;远离可见病灶的区域NAA、Cr和Cho含量及比例正常。结论　1H MRS发现物质代谢变化是有规律的 ,变化的区域大于MRI中可见病变区 ,为早期诊断提供了可能性。     

鼻咽癌放射治疗后放射性脑损伤的扩散张量成像与1H-MR波谱研究

目的 探讨双侧颞叶脑组织在鼻咽癌放射治疗后不同时期的DTI与1H-MRS变化特点.方法 选择48例鼻咽癌放射治疗后常规MRI表现正常的患者(患者组)及24名健康志愿者(正常组)行DTI及1H-MRS检查,将扫描图像进行后处理和波谱分析,测量双侧颞叶DTI的各向异性分数(FA)值、ADC值及3个本征值λ1、λ2、λ3,以及1H-MRS中双侧颞叶前部白质N-乙酰天冬氨酸(NAA)/胆碱(Cho)、NAA/肌酸(Cr)及Cho/Cr比值,并将鼻咽癌放射治疗后患者按放射治疗后不同时期分为放射治疗后0～6、6～12、>12个月,分别定义为患者组1(16例)、2(6例)、3(26例),计算放射治疗后双侧颞叶脑组织各测量指标数值.所得数据采用单因素方差分析.结果 鼻咽癌放射治疗后6个月内、6～12个月、12个月后以及正常组DTI的FA值分别为0.445±0.017、0.460±0.016、0.461±0.025、0.473±0.023,ADC值分别为(8.51±0.43)×10-4、(8.48±0.34)×10-4、(8.40±0.33)×10-4、(8.68±0.57)×10-4mm2/s,3个本征值中最大本征值λ1分别为(1.251±0.065)×10-3、(1.293±0.051)×10-3、(1.317±0.074)×10-3、(1.350±0.091)×10-3 mm2/s,以上3个指标组间差异均有统计学意义(F值分别为10.873、3.399、9.750,P值均<0.05).λ2、λ3值组间比较差异无统计学意义.1H-MRS的NAA/Cho分别为0.910±0.112、0.972±0.101、1.060±0.095、1.261±0.105,NAA/Cr分别为1.212±0.236、1.208±0.183、1.228±0.236、1.435±0.225,组间差异均有统计学意义(F值分别为52.840、8.176,P值均<0.01).Cho/Cr组间比较差异无统计学意义.结论 DTI结合1H-MRS在鼻咽癌放射治疗后监测评价脑组织的放射损伤程度方面具有一定的指导作用,可为放射性脑损伤的动态早期监测提供科学依据.     

胆红素脑病的MRI诊断

目的 探讨MRI对胆红素脑病的诊断和预后判断价值.方法 分析26例临床确诊为胆红素脑病患儿的MRI特点,MRI采用GE Signa EXCITE1.5T超导型磁共振扫描系统,扫描图像包括T1WI、T2WI和DWI,由2名放射科医师采用单盲法分析MR图像.结果 首次检查9例为新生儿,8例表现为双侧苍白球对称性T1WI高信号,5例伴丘脑腹外侧对称稍高信号;2例双侧苍白球对称性T2WI稍高信号.1个月以上随访的25例(25/26)均表现为双侧苍白球对称性T2WI高信号,4例T1WI呈低信号,1例T1WI呈稍高信号;25例DWI未见明显异常信号改变.1例3个月后 DWI呈高信号,而11个月时DWI高信号消失,所见双侧苍白球对称T2WI高信号也消失.结论 胆红素脑病患儿的MR影像具有特征性,可为临床早期诊断及预后判断提供重要信息.     

肌萎缩侧索硬化症的~1H-MR波谱研究

目的 探讨肌萎缩侧索硬化症(ALS)患者的1H-MRS表现及其与临床评分的关系.方法 对15例临床确诊及拟诊为ALS的患者(ALS组)和15名年龄相匹配的健康志愿者(对照组)进行1H-MRS扫描,采用单体素平均TE选择性单点分辨波谱序列(TE-Averaged PRESS).扫描图像经后处理,分别获得以中央前回为中心的运动皮层和内囊后肢处的以下成分波峰:N-乙酰天门冬氨酸(NAA)、谷氨酸(Glu)、谷氨酸复合物(Glx)以及肌酸(Cr),并测量NAA/Cr、Glu/Cr和Glx/Cr峰高相对值.采用t检验比较两组间各比值的差异,并分析上述各值与ALS患者临床评分的直线相关关系.结果 ALS组运动皮层和内囊后肢的NAA/Cr值为1.91±0.34、1.53±0.17,对照分别为2.23±0.33,1.66±0.07.两组间差异有统计学意义(t值分别为4.25、2.90,P值分别为0.00、0.01).AIS组运动皮层和内囊后肢Glu/Cr为0.34±0.05、0.29±0.06,Glx/Cr为0.40±0.04、0.33±0.06,均高于对照组(Glu/Cr分别为0.30±0.03、0.25±0.04,Glx/Cr分别为0.32±0.05,0.26±0.03),两组间差异有统计学意义(t值分别为2.56、2.40、7.34、5.30,P值分别为0.02,0.03、0.00、0.00).ALS患者Norris评分值为(57±8)分,ALS功能分级评分(ALSFRS)值为(29±4)分.直线相关分析发现ALS患者运动皮层Glx/Cr值与Norris评分呈负相关(r=-0.75,P=0.00),而与ALSFRS值无相关性.结论 ALS患者谷氨酸类代谢物含量升高.(1)H-MRS可反映ALS患者脑内代谢物的变化特征.     

Balo病同心圆硬化的MRI、质子波谱和活检病理对照研究

目的 描述Balo病同心圆硬化的MRI和质子波谱（^1H－MRS）特征。方法 报告了3例经活检病理证实的Balo病同心圆硬化的MRI表现，其中1例同时进行了^1H－MRS检查。结果 3例病人中，2例多发、1例单发。病灶均位于中央白质区，呈典型的同心圆形改变，增强扫描呈典型层状“洋葱皮样”增强。 ^1H-MRS示病变区N-乙酰天冬氨酸（NAA）降低、胆碱增高并出现异常脂质峰。结论 Balo氏同心圆硬化MRI和^1H－MRS表现具有特征性，MRI应作为本病的首选检查方法。     

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.     

Studying neonatal bilirubin encephalopathy with conventional MRI,MRS, and DWI

Introduction  The purpose of this study was to evaluate the diagnostic value of conventional magnetic resonance imaging (MRI), proton magnetic resonance spectroscopy (¹H-MRS), and diffusion-weighted imaging (DWI) for neonatal bilirubin encephalopathy. Methods  We collected conventional MRI in 24 neonates with neonatal bilirubin encephalopathy. We performed ¹H-MRS and DWI sequences to nine of the 24 patients and seven age-matched healthy control subjects. Multiple-voxel ¹H-MRS data were acquired using PRESS pulse sequence with TE = 135 ms and TR = 1500 ms. The spectroscopic regions of interest were the bilateral basal ganglia and thalamus with a 1.0 mL spatial resolution. The data from DWI were collected by using a single shot-spin echo-echo planar imaging sequence with TR/TE: 2900/98, and imaging regions were also focused on the bilateral basal ganglia and thalamus. Results  Nineteen of the 24 patients had abnormal T₁-weighted image hyperintensity in the globus pallidus, but these lesions appeared as normal T₂-weighted image intensity in the same region. Ten of the 24 patients had T₁-weighted image high signal intensity in the subthalamic nucleus and appeared as normal intensity in the region for the T₂-weighted images. The peak area ratios of NAA/Cho and NAA/Cr were significantly decreased (t-test, P < 0.05) in the patients compared to the controls in the basal ganglia. Conclusion  Conventional MR imaging and ¹H-MRS are important complementary tools in the diagnosis of neonatal bilirubin encephalopathy. The study provides important information for applying these MR modalities to evaluate neonates with bilirubin encephalopathy.