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1.
原发性支气管肺癌MRI相对信号强度与PCNA相关性的研究   总被引:7,自引:0,他引:7  
目的 探讨肺癌组织的MRI相对信号强度与增殖细胞核抗原(PCNA)之间的关系。材料与方法 26例肺癌患者,术前用Resonex 0.38T磁共振成像系统,行横断而SE T1WI,GR序列成像,增强后行SE T1MI。术后标本采用ABC免疫组化技术,观察PCNA在26例肺癌中的表达。结果 Gd-DTPA增强后增殖活性较低的肿瘤细胞(5%〈PCNA≤50%),其MRI相对信号强度啬值明显瘤细胞吸收Gd  相似文献   

2.
三倍量(0.3mmol/kg)国产Gd-DTPA增强MR探查脑膜转移瘤的研究   总被引:3,自引:0,他引:3  
目的 评价三倍量(0.3mmol/kg)国产Gd-DTPA增强MR探查脑膜转移瘤的效果。材料与方法 用国产Gd-DTPA三倍量增强MR检查110例临床怀疑脑转移瘤患者。先行平扫,然后静脉注射常规量(0.1mmol/kg)国产Gd-DTPA。注射后即刻行T1WI扫描,20分钟后行延迟扫描。距第1次注射30分钟后,再注射0.2mmol/kg的Gd-DTPA,从而达到累积剂量0.3mmol/kg。第2次  相似文献   

3.
目的:采用磁化传递对比成像(MTC)对脑膜瘤增强后的T1加权图像(T1WI)上的病程强化程度与常规增强后T1WI病灶强化程度进行定量研究。方法:10例脑膜瘤病人按序进行自旋回波(SE)的T1WI,增强后T1WI及增强后MTCT1WI成像,分别测量病灶及正常脑白质(背景)信号强度,计算信噪比及效价。结果:在常规增强后T1WI及增强后MTCT1WI上病灶信号为:107.2±13.7和129.3±9.36。而背景信号为:107.2±37.4和75.9±8.03,信噪比分别为0.339及0.687,增强效价为2.03。结论:同时使用造影剂与MTC结合的T1WI可增强病灶与背景的对比效应,提高脑膜瘤与周围脑组织的对比度,有利于更为精细的观察。  相似文献   

4.
肺癌MRI与癌细胞核DNA含量及S期分数的相关性   总被引:1,自引:0,他引:1  
探讨肺癌MRI信号及形态特征与DNA倍体的关系。材料和方法:26例原发性支气管肺癌患者,术前用Resonex0.38T磁共振成义行冠状面及横断面成像(SE T1WI和GR),增强后行横断面SE T1WI。术后肺癌标本用细胞图像分析仪,测定每例患者的DNA含量及S期分数(SPF)。结果:未增强T1WI异倍体肿瘤信号强度比显著大于二倍体肿瘤的信号强度比。异位体肿瘤的SPF值也显著大于二倍体肿瘤,MRI  相似文献   

5.
3cm以下小肝癌的磁共振成像与病理对照研究   总被引:3,自引:0,他引:3  
笔者分析了26例小肝癌(SHCC)的MRI并与病理对照。结果表明:T_1WI上80.8%为低信号,PDWI上100%为高信号,T_2WI上84.6%为高信号;T_1WI和T_2WI上信号多为轻度和/或中等度低信号及高信号;T_1WI上84.6%信号均匀,T_2WI上61.5%信号不均。在大于2cm组,信号不均在T_1WI和T_2WI间差异非常显著(x ̄2检验,P<0.01);对于中等度分化和梁状型的SHCC其信号不均在T_1WI和T_2WI上差异非常显著(x ̄2检验,P<0.01和P<0.05)。SHCC的大小与信号强度间无统计学意义(x ̄2检验,P>0.05),病理分型与信号强度间无统计学意义(x ̄2检验,P>0.05),而信号强度与病理高分化间由于本组分化Ⅰ级者太少,故未作统计;PDWI和T_2WI上高信号环在组织学上未见明确对应病理变化。  相似文献   

6.
中场强磁共振尿路水成像技术与临床应用初探   总被引:4,自引:2,他引:2  
目的 评价中场强(0.5T)磁共振单激发快速自旋回波9SSFSE0尿路水成像(MRU)技术及其临床应用价值。材料与方法 42例正常和悄路梗阻患者,在GE 0.5T超导MR成像仪上采用SSFSE进行MRU成像;38例加作2D FSE重T2WI,经最大信号强度投影(MIP)重建MRU图像。结果 采用SSFSE所得MRU图像可清晰显示正常尿路,效果比2D FSE重T2WI经MIP重建所得MRU钉佳,尿路  相似文献   

7.
余卫  冯逢 《中华放射学杂志》1997,31(11):748-753
目的:旨在评估强直性脊柱炎(AS)患者骶髂关节炎的MR影像特征,并比较X线平片、CT和MR影像在诊断骶髂关节炎中的作用。材料与方法:搜集24例AS患者,分别行X线平片、CT和MRI检查。增强前MR扫描序列包括SE T1WI、FSE T2WI和梯度回波的准T2WI(GR T2^*WI)。增强后MR扫描序列参数与增强前SE T1WI相同。另选9例志愿者,行MR平扫检查。结果:8例志愿者16个骶髂关节的  相似文献   

8.
目的:评价胸部MRA的临床意义,材料与方法,本文搜集19例胸部有块病变,其中肺癌14例,纵膈病变5例,19例共行20次MRI及MRA检查,常规MR成像序列为冠状T1WI,轴位T1WI和T2WI在此基础上行MR血管成像(MRA)。MR扫描机为GESigna1.5T超导型,工作站,SUNMicrosystemAdvantageWindows1,2,6。冠状MRA在工作站上行最大强度投影(MIP)重建。  相似文献   

9.
Gd-DTPA在诊断卵巢肿块中的应用及评价   总被引:1,自引:0,他引:1  
目的:正确评价Gd-DTPA在诊断卵巢病变中的作用。材料和方法:采用MR的T2加权成像(T2WI)和增强前后T1加权成像(T1WI)3种序列,对具有手术病理结果的75例110个卵巢肿块进行回顾性分析。结果:静注Gd-DTPA后有以下变化特征:(1)恶性肿瘤特征显示正确率由83.3%升至100.0%。(2)良、恶性肿块的实质均有明显强化,其强化率之间无显著性差异(P>0.05);不同强化时程,绝大多数病变的强化率也无明显差异(P>0.05)。(3)22例手术病理明确分期的恶性肿瘤患者中,常规平扫T1WI及T2WI,分期正确率为59.1%,运用造影剂后升至77.3%,结合MRI的3个序列可达81.8%。结论:Gd-DTPA可改善对肿瘤的描述和对其内部结构的显示,提高对恶性肿瘤诊断及分期的正确率,但Gd-DTPA增强无特异性,尚不能依据信号的强化程度来判断病灶的性质,恰当的选择使用对临床具有重要的指导意义。  相似文献   

10.
MRI对脊髓亚急性联合变性的诊断价值   总被引:21,自引:0,他引:21  
目的 评价MRI诊断脊髓亚急性联合变性(SCD)的价值。方法 7例维生素B12缺乏而临床怀疑SCD的患者进行了MR扫描。扫描包括矢状面T1WI和矢状面、轴面T2WI,其中4例行钇喷替酸葡甲胺(Gd-DTPA)增强扫描,4例于治疗后行MRI复查结果所有病例的T2WI均显示。戏髓或胸髓后索高倍病灶,有4例同时出现侧索病灶,T1WI未见异常,Gd-DTPA增强鞠强化。有4例在维生素B12治疗后半年及1年  相似文献   

11.
目的 :观察联合使用SPIO和Gd DTPA对大鼠肝癌模型的增强特点。材料和方法 :制作 3 0只大鼠肝癌模型 ,增强前后行MR扫描 ,平扫序列包括SE、TSE、GRE的T1、T2WI序列。增强扫描分为 4组 ,其中Gd +SPIO联合增强组 10只 ,先注射Gd DTPA ,行SE、GRET1WI扫描 ,随后给予SPIO造影剂 ,扫描序列同平扫 ;SPIO +Gd联合增强组 10只 ,先注射SPIO ,行SE、GRET1WI扫描 ,12min后再给予Gd DTPA ,扫描序列同平扫 ;Gd、SPIO增强组各为 5只 ,增强扫描序列同平扫。分析各增强扫描组中病灶的增强特点。结果 :两种联合增强方法中 ,肝脏信号强度在所有扫描序列中均较平扫时下降 ,但与SPIO增强组无差异 ;病灶的SNR、CNR在SE、GRET1WI中明显高于平扫和SPIO、Gd DTPA增强法 ;在T2WI中病灶的SNR、CNR和单独使用SPIO无显著性差异。两种联合增强方法之间的SNR和CNR在每种扫描序列中没有显著性差异。结论 :SPIO和Gd DTPA联合增强方法利用了两种造影剂的优势 ,增加了肿瘤病变的对比 ,可提高发现病变的几率。  相似文献   

12.
目的 评价快速注射结合缓慢融入对比剂Gd-DTPA对血池T1弛豫效果的影响.方法 对15例冠心病患者行冠状动脉MRA检查.先以1.50 ml/s流率注射对比剂Gd-DTPA 10 ml,再以0.05 ml/s流率注射20 ml,然后对冠状动脉同1支血管行2次扫描,获得注射对比剂后5和15 min的图像.计算增强前后图像的信噪比(SNR)和对比噪声比(CNR),并以t检验进行比较.结果 注射对比剂后5 min图像的SNR和CNR(35.37±6.84和21. 57±6.08)明显高于增强前图像的SNR和CNR(27.38±6.24和13.19±6.50).注射对比剂15 min后图像的SNR(33.81±9.43)高于增强前,但没有统计学意义(t=1.885,P=0.074),图像的CNR(21.20±7.65)明显高于增强前.注射对比剂后5和15 min图像的SNR和CNR没有明显的区别.结论 快速注射结合缓慢融入Gd-DTPA,可以获得延长短T1效应的采样时间,以适应冠状动脉MRA多期扫描的需求.  相似文献   

13.

Purpose:

To evaluate the effect of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA) on T2‐weighted imaging (T2WI) and diffusion‐weighted imaging (DWI) for the diagnosis of hepatocellular carcinoma (HCC).

Materials and Methods:

The phantom signal intensity was measured. We also evaluated 72 patients including 30 patients with HCC. T2WI and DWI were obtained before and then 4 and 20 min after injecting the contrast medium. The signal to noise ratio (SNR), contrast to noise ratio (CNR), and apparent diffusion coefficient (ADC) were calculated in the tumor and liver parenchyma.

Results:

The phantom signal intensity increased on T2WI at a concentration of contrast medium less than 0.2 mmol/L but decreased when the concentration exceeded 0.4 mmol/L. SNR of the liver parenchyma on T2WI was significantly different between before and 4 min after injecting the contrast medium, while there were no significant differences between before and 4 and 20 min after injection. On T2WI, SNR, and CNR of HCC showed no significant differences at any time. SNR, CNR, and ADC of the liver parenchyma and tumor on DWI also showed no significant differences at any time.

Conclusion:

It is acceptable to perform T2WI and DWI after injection of Gd‐EOB‐DTPA for the diagnosis of HCC. J. Magn. Reson. Imaging 2010;32:229–234. © 2010 Wiley‐Liss, Inc.  相似文献   

14.
增强MRI对周围性肺结节的诊断价值   总被引:10,自引:0,他引:10  
目的:探讨Gd-DTPA增强MRI对孤立性肺结节的诊断价值.材料和方法:对29例孤立性肺结节行平扫和Gd-DTPA增强MR检查,Gd-DTPA按0.1mml/kg体重静脉内注射,观察不同性质结节的强化模式差异,测量增强前后信号强度变化.结果:恶性肿瘤明显强化,而良性肿瘤不强化或轻度强化,两者有显著差异(P<0.01).部分结核瘤表现为特征性的“周边薄层环状”强化.结论:良恶性结节间强化程度和模式有差异,增强MR对CT不能确诊的肺结节有重要鉴别诊断价值.  相似文献   

15.
OBJECTIVES: The objectives of this study were to analyze the differences in contrast enhancement using gadobenate dimeglumine (Gd-BOPTA or MultiHance) at 3 T versus 1.5 T and to compare Gd-BOPTA with a standard gadolinium chelate, gadopentetate dimeglumine (Gd-DTPA or Magnevist), at 3 T in a rat glioma model. MATERIALS AND METHODS: Twelve rats with surgically implanted gliomas were randomized to either comparing Gd-BOPTA at 1.5 T versus 3 T (n=7) or comparing Gd-BOPTA and Gd-DTPA at 3 T (n=5). Matched T1-weighted spin-echo techniques were used for both comparisons and the order of examinations was randomized. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and lesion enhancement (LE) were evaluated using a region-of-interest analysis. A veterinary histopathologist evaluated all brain specimens. RESULTS: In the evaluation of Gd-BOPTA at 3 T and 1.5 T, there were significant increases in SNR, LE, and CNR at 3 T. Average increases in brain and tumor SNR were 93% (P<0.0001) and 92% (P<0.0001), respectively. CNR increased by 121% (P<0.0001). Comparison of Gd-BOPTA and Gd-DTPA at 3 T demonstrated significantly higher CNR and LE with Gd-BOPTA. CNR increased by 35% (P=0.002). LE increased by 44% (P=0.03). CONCLUSIONS: Gd-BOPTA provides significantly higher CNR at 3 T compared with 1.5 T and also demonstrates significantly higher CNR when compared with a standard Gd-chelate at 3 T. As a result of transient protein binding, Gd-BOPTA may be superior to standard gadolinium chelates in neurologic imaging at 3 T.  相似文献   

16.
肝脏特异性磁共振对比剂——菲立磁的临床应用初探   总被引:7,自引:1,他引:6  
目的 探讨菲立磁增强MRI检查对肝脏疾病的临床应用价值。材料与方法 对22例经CT或MRI检查确定或怀疑有肝病变者进一步行菲立磁增强MRI检查,分别测量增强前后肝脏、病变及背景噪声的T2WI信号强度(SI),计算增强前后肝脏及病变的信噪比(SNR)、对比噪声比(CNR)。结果 增强后肝脏的SI、SNR明显降低(P<0.01);恶性病变的SI、SNR变化不明显(P>0.05)。囊肿、血管瘤增强后T2WI SI下降不明显。增强后病变-肝脏CNR比增强前明显增高(P<0.01)。增强后0.5小时与3小时相比肝脏SNR以及CNR无差异(P>0.05)。增强后病变的检出数量增加,而且其边界、大小显示更清楚。结论 菲立磁增强磁共振扫描可显著降低肝脏T2WI SI,而对恶性肿瘤T2WI信号的影响不明显,显著提高了恶性肿瘤-肝脏的CNR。因此,它对恶性肿瘤的检出及定性诊断具有临床意义。  相似文献   

17.
不同MR扫描序列在SPIO增强大鼠肝癌模型的对比研究   总被引:3,自引:2,他引:1       下载免费PDF全文
目的:比较多种扫描序列超顺磁氧化铁(SPIO)增强扫描对显示大鼠肝癌病灶的能力,找出最佳扫描方案。TSE T2WI、SE双回波的T2WI+PDWI、GRE T1WI、T2^*WI,分析增强前后大鼠肝癌病灶的强化特征,并进行病理学检查对照分析。结果:注射SPIO对比剂后,所有扫描序列均显示肝脏的信号强度较增强前有不同程度的下降,肝癌病灶CNR均分别高于平扫。增强后GRE T2^*WI中病灶的CNR明显高于其它序列,但增强后TSE T2WI和常规SE T2WI在显示病变的SNR、CNR方面没有显著性差异。结论:SPIO增强后检测肝癌病灶的各种序列中,以GRE T2^*WI最为敏感,其次是双回波的T2WI+PDWI序列。  相似文献   

18.
PURPOSE: To compare contrast characteristics and image quality of 1.0 M gadobutrol with 0.5 M Gd-DTPA for time-resolved three-dimensional pulmonary magnetic resonance angiography (MRA). MATERIALS AND METHODS: Thirty-one patients and five healthy volunteers were examined with a contrast-enhanced time-resolved pulmonary MRA protocol (fast low-angle shot [FLASH] three-dimensional, TR/TE = 2.2/1.0 msec, flip angle: 25 degrees, scan time per three-dimensional data set = 5.6 seconds). Patients were randomized to receive either 0.1 mmol/kg body weight (bw) or 0.2 mmol/kg bw gadobutrol, or 0.2 mmol/kg bw Gd-DTPA. Volunteers were examined three times, twice with 0.2 mmol/kg bw gadobutrol using two different flip angles and once with 0.2 mmol/kg bw Gd-DTPA. All contrast injections were performed at a rate of 5 mL/second. Image analysis included signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements in lung arteries and veins, as well as a subjective analysis of image quality. RESULTS: In patients, significantly higher SNR and CNR were observed with Gd-DTPA compared to both doses of gadobutrol (SNR: 35-42 vs.17-25; CNR 33-39 vs. 16-23; P < or = 0.05). No relevant differences were observed between 0.1 mmol/kg bw and 0.2 mmol/kg bw gadobutrol. In volunteers, gadobutrol and Gd-DTPA achieved similar SNR and CNR. A significantly higher SNR and CNR was observed for gadobutrol-enhanced MRA with an increased flip angle of 40 degrees. Image quality was rated equal for both contrast agents. CONCLUSION: No relevant advantages of 1.0 M gadobutrol over 0.5 M Gd-DTPA were observed for time-resolved pulmonary MRA in this study. Potential explanations are T2/T2*-effects caused by the high intravascular concentration when using high injection rates.  相似文献   

19.
马小龙  陆建平  刘崎  金爱国   《放射学实践》2009,24(9):976-981
目的:比较超微超顺磁性氧化铁(USPIO)和钆对比剂在磁共振图像上增强动脉粥样硬化斑块的异同。方法:20只新西兰大白兔高脂喂养8周,存活18只,分为对照组和实验组,每组各9只。使用磁共振在心电门控下对两组兔主动脉斑块进行检测,再给对照组注射钆对比剂,实验组注射USPIO对比剂,并分别于注射后即时、24、36和48 h进行扫描。扫描序列为二维时间飞跃法、快速自旋回波T1WI、脂肪抑制的快速自旋回波序列T1WI和快速自旋回波序列T2WI。比较各组兔主动脉硬化斑块内增强前后以及增强后不同时期的脂肪抑制T1WI和T2WI,对比噪声比(CNR)值变化差异。将两组动物处死后取出胸主动脉进行大体普鲁士蓝染色和切片显微镜观察。结果:对照组主动脉硬化斑块注射钆对比剂后T1WI显著强化,CNR值明显上升,24 h后回归注射前状态;T2WICNR值轻度下降,24 h后回归正常。实验组硬化斑块注射USPIO后T1WI显著强化,CNR值明显上升,24 h后有所下降,但明显高于注射前,48 h和72 h后CNR值持续上升;T2WI注射后信号显著降低,24 h后CNR值有所上升,但仍然低于注射前,48 h和72 h CNR值持续下降。实验组兔胸主动脉和切片普鲁士蓝染色阳性,对照组显示阴性。结论:相对于钆对比剂,超顺磁性、超长时间的血浆半衰期以及能够被巨噬细胞特异性吞噬的特性,使得常规剂量的USPIO可以同时引起强化组织信号在T1WI及T2WI上显而易见的变化,并且能够保持长时间的持续强化。  相似文献   

20.
目的:研究椎管内微小占位性病变的MRI特征及其对病变定性、定位诊断的意义。材料与方法:24例椎管内微小占位性病变患者(男12例,女12例,年龄23~67岁,平均29.1岁)均经PHILIPS 1.0NT型MR仪行常规T_1WI、T_2WI磁共振成像,其中6例又经Gd-DTPA增强扫描。全部病例的椎管内占位病变均经病理证实,并对其MRI表现进行了回顾性分析。结果:24例的病变经病理证实,18例为胚胎源性肿瘤(10例表皮样囊肿,4例皮样囊肿,4例畸胎瘤),4例为神经源性肿瘤(3例神经鞘瘤,1例神经纤维瘤),以及脊膜瘤与脂肪瘤各1例。各种占位性病变的MRI表现随其不同的组织学来源而有很大差别。表皮样囊肿多为均质长T_1长T_2信号。皮样囊肿以短T_1,长T_2信号为主。畸胎瘤呈混杂信号。神经鞘瘤为T_1WI低信号、T_2WI高信号,Gd-DTPA增强扫描后,囊壁均匀强化,偶见强化附壁结节。神经纤维瘤呈均质长T_1、长T_2信号,Gd-DTPA增强扫描后,病灶呈异常对比增强。脊膜瘤呈长T_1、稍长T_2信号,Gd-DTPA增强扫描后,病灶呈异常对比强化,并见局部硬脊膜增厚强化而形成的硬膜尾征。结论:各种病变的MRI表现随其组织学来源不同而有明显差异,它们在椎管内微小占位性病变的定性、定位诊断中起着重要作用,其诊断准确性优于X线椎管造影与CT。  相似文献   

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