肝脏肿瘤手推团注动态MR增强扫描方法及2种对比剂效果比较

目的介绍肝脏病变手推团注动态MR增强扫描方法,对比离子型钆喷酸葡胺和非离子型钆双胺MR对比剂在肝脏肿瘤性病变动态增强的效果。方法185例肝脏肿瘤患者分2组:第1组91例(男52例,女39例),采用非离子型钆双胺MR对比剂(Gd-DTPA-BMA);第2组94例(男55例,女39例),采用离子型钆喷酸葡胺MR对比剂(Gd-DTPA)。行手推团注动态MR增强扫描。结果①手推团注动态强化效果总满意率75.14%,一般率24.32%,差0.54%。②2组间动态强化效果t检验无显著性差异,P>0.05。③各类肝脏肿瘤动态强化表现组间t检验无显著性差异,P>0.05。结论肝肿瘤手推团注动态MR增强扫描,Gd-DTPA-BMA和Gd-DTPA均可达到满意的增强效果。完全可满足临床诊断要求。     

颈动脉三维增强磁共振血管成像技术初步探讨

目的　探讨颈动脉三维增强磁共振血管成像 (3DCEMRA)方法和影响图像质量的因素。方法　使用 1.5T超导型MR扫描机 ,头部、颈部以及部分腰椎相控阵线圈。对 48例病人进行颈动脉 3DCEMRA增强扫描。检查时 ,嘱患者屏气 ,于静脉内团注钆双胺 (Gd -DTPA -BMA)对比剂后进行颈动脉期扫描 ,用 3DFLASH序列采集图像。结果　检查的病例 96%获得了满意的图像 ,经MIP和MPR重建后 ,能够清楚显示颈动脉正常解剖结构和病变的部位、大小及其狭窄程度。 2 3例经数字减影血管造影(DSA)或 /和超声以及手术证实的病例中 ,3DCEMRA显示颈动脉的特异性和敏感性均为 10 0 %。结论　高质量的颈动脉MRA图像依赖于注药后扫描时机的准确性 ,注药流速与总量的合理性 ,合适的扫描序列 ,以及操作者的技巧和熟练程度     

不同剂型MR造影剂在肝脏病变增强扫描中的应用

顺磁性MR造影剂,钆喷酸葡胺(Gd-DTPA)已广泛应用于MRI的各项检查,有效地提高了MRI的诊断水平。钆双胺MR造影剂(GD-DTPA-BMA)是一种非离子型的二乙烯三胺五乙酸二甲胺的钆螯合物。其安全性和在中枢神经系统MRI检查中的有效性国外已有报道[1]。本研究旨在比较GD-DTPA-BMA和GD-DTPA在肝脏病变增强扫描中的增强效果。1对象和方法1.1对象随机选择2000年8月～2002年5月肝脏增强扫描患者60例,其中男32例,女28例,年龄33～76岁,均无心脑肝肾功能衰竭。随机分两组,第一组:30例(男女各15例),年龄33～70岁,平均50.26岁,采用非离子型钆…     

局灶性肝脏肿块:MR、CT动脉门脉造影检查的比较

作者对11例(共31个)局灶性肝脏肿块患者作了经动脉门脉造影MR(MRAP)和CT(CTAP)检查的对比研究。其中8例来自直肠癌转移,1例胰腺类癌转移,1例胆管癌,1例肝细胞癌。男6例,女5例,年龄38～64岁。所有病例在血管造影检查前行超声和团注动态增强CT或MR钆增强扫描检查,在造影后3～     

离子型和非离子型MR对比剂在MR颈动脉动态增强中的应用

目的:探讨离子型和非离子型MR对比剂在MR颈动脉动态增强扫描中的应用价值。材料和方法:将2005-09~2006-06行颈动脉动态增强扫描的56例患者,随机分为A、B两组。A组28例,用离子型对比剂(Gd-DTPA),B组28例采用非离子型对比剂(Gd-DTPA-BMA)。用3.0TMR机行动态增强扫描。A、B两组的扫描参数相同。结果:56例均完成颈动脉动态增强扫描。两种对比剂的增强效果无明显差异(P>0.05)。两组对比剂不良反应中,A组1例出现恶心,B组1例出现发热症状的轻微不良反应外,两种对比剂在使用的安全性上无差异。结论:两种对比剂的增强效果及使用安全性无明显差异,非离子型对比剂是MR血管造影动态增强较为理想的对比剂。     

钆标记单克隆抗体片段对荷瘤裸鼠MR免疫成像的研究

目的　探索标记钆(Gd)对抗体活性的影响并分析MR增强效果。方法　(1)取20只裸鼠制作荷大肠癌动物模型;(2)将C.DTPA(DTPA环二酸酐)与抗人大肠癌（CL-3）单克隆抗体片段F(ab)′2按C/P(DTPA环二酸酐与抗体片段的摩尔比值)=2∶1和5∶1分A、B两组,偶联制备Gd-F(ab)′2-DTPA;(3)MR扫描18只裸鼠随机分3组,作平扫和增强扫描,2只作瘤内直接注射,取T1WI信号强度数据,进行相对标准化处理。结果　标记后A、B两组抗体免疫结合率分别为74%和62%。增强扫描,肿瘤均有轻度强化,B组(31.67±1.12)比A组(24.45±1.92)明显。结论　随着C/P的增加,标记抗体片段的活性下降,但MR增强效果有所增加且F(ab)′2-DTPA-Gd的增强作用具有特异性。     

手推注射减量稀释钆对比剂在垂体MRI动态增强扫描中的应用

目的研究减量稀释钆对比剂在垂体MRI动态增强扫描中的应用效果。方法连续性将45例志愿者随机分成2组,其中甲组22例采用减量稀释对比剂(0.07mmol/kg钆喷酸葡胺与0.15ml/kg生理盐水混合)进行手推注射动态增强扫描,乙组23例采用半剂量(0.05mmol/kg)钆喷酸葡胺双筒高压注射器进行动态增强扫描,比较2组间垂体强化的特点、垂体与海绵窦之间的分界。然后连续性将153例疑有垂体病变的患者随机分成2组进行MRI动态增强扫描,其中A组79例采用减量稀释对比剂进行手推注射动态增强扫描,B组74例采用半剂量钆喷酸葡胺双筒高压注射器进行动态增强扫描,比较2组间垂体病变的检出率以及边界显示情况。结果志愿者中两种注射方法垂体均见明显强化,均在约1min内达到强化峰值,乙组垂体强化程度高于甲组(P0.05),垂体与海绵窦分界显示效果接近(P=0.085)。两组患者垂体病变的检出率(P=0.787)、垂体病变的边界显示效果(P=0.682)接近。结论手推注射减量稀释钆对比剂在垂体MRI动态增强扫描中的应用效果与采用高压注射半剂量对比剂效果相仿。     

国产高压注射器在肝脏动态CT扫描中的应用

ＣＴ增强扫描已广泛运用于临床,造影剂注射方式有滴注、手推法团注和压力注射器团注等,团注的增强效果优于滴注［１,２］。手推法团注因注射速度仍较慢、且欠均匀,我们用国产高压注射器团注造影剂进行了肝脏动态ＣＴ扫描,并取得了良好的效果。材料与方法本组６４例中男４２例,女２２例,年龄３０岁～７２岁。其中原发肝癌２４例,肝血管瘤２０例,肝转移癌１５例。检查方法：常规平扫发现病灶后,以较大病灶中心层面或发现病灶最多层面作动态ＣＴ层面,用无锡产ＤＧＺ—１型电动高压注射器经１７～２０号塑料套管针（避免用蝴蝶针）从…     

MR多时相动态增强扫描技术的临床应用

目的探讨MR多时相动态增强扫描的方法及其在MR诊断中的价值。材料与方法回顾性分析988例(男744例,女244例,年龄22～82岁)多时相动态增强扫描的资料。结果增强效果优865例,占87.5％;增强效果中97例,占9.9％;增强效果差26例,占2.6％。结论多时相动态增强扫描对各种病变特别是肿瘤性病变的定性诊断有重要价值,合理地选择技术参数是获得高质量图像的关键。     

腹部CT实行三种静脉注射造影剂方法的比较

作者在腹腔和盆腔CT检查中进行了三种造影方法的比较。90例病人(48例男性和42例女性),依静脉注射方法分为三组:(1)单次团注强化(150或175ml),当扫描至膈顶水平时开始用压力注射器注射(2 ml/秒)。(2)分次/团注技术,当扫描到膈顶水平时开始团注100或125ml,当扫描到髂棘水平时再团注50ml(2 ml/秒)。 (3)当扫描到膈顶水平时,初始手推团注100或125ml,随后马上快速静脉滴注50ml(输液器在病人上1.8m)。所有病人用60%泛影葡胺。注射造影剂30秒后开始扫描,以保证在强化的非平衡期间完成肝脏扫描。层厚1 cm,从膈顶到耻骨联合部     

Hepatic tumors: dynamic MR imaging

Thirty-six patients with hepatic tumors (28 hepatocellular carcinomas, seven cavernous hemangiomas, one metastatic tumor) were examined with serial magnetic resonance (MR) imaging, after a bolus intravenous injection of 0.05 mmol/kg gadolinium-diethylenetriaminepentaacetic acid. A typical MR imaging pattern for hemangiomas (present in five of seven cases [71.4%]) was a lesion of diminished signal intensity on precontrast images, peripheral contrast enhancement during the bolus dynamic phase, and complete fill-in of high signal intensity on delayed scan images. Twenty-eight hepatocellular carcinomas showed a variety of contrast enhancement patterns during the dynamic phase. In 21 patients (75%), there was no area of high signal intensity within the tumor on the delayed phase. A peripheral halo with delayed enhancement was noticed in 12 patients (42.8%) Histologic correlation in hepatocellular carcinomas showed that the degree of contrast enhancement corresponded to tumor vascularity and that the peripheral halo corresponded to fibrous capsular structure.     

临床常用MR对比剂不良反应的观察

目的：探讨临床常用MR对比剂（Gd-DTPA、Gd-DTPA-BMA、Gd-BOPTA）的不良反应及安全性。方法：观察行MRI增强检查的12588例患者注射不同MR对比剂前后的反应（Gd-DTPA 9871例、Gd-DTPA-BMA 2085例、Gd-BOPTA632例）,分析常用MR对比剂不良反应的发生率及其严重程度。结果：在所有注射MR对比剂的患者中,不良反应总发生率为0.58%（73/12588）,其中Gd-DTPA不良反应发生率为0.15%（15/9871）,Gd-DTPA-BMA不良反应发生率为0.10%（2/2085）,Gd-BOPTA不良反应发生率为8.86%（56/632）。在MR对比剂检查患者中无死亡病例。Gd-DTPA-BMA与Gd-DTPA之间不良反应发生率差异无统计学意义（χ^2=0.38,P〉0.05）;Gd-BOPTA与Gd-DTPA、Gd-DTPA-BMA之间不良反应发生率差异有统计学意义（χ^2=671.04,P〈0.05;χ^2=178.34,P〈0.05）。结论：临床常用MR对比剂不良反应发生率低,临床应用安全性高。     

动态及延时增强磁共振成像对肝血管瘤诊断的评价

目的:研究动态增强及延迟增强扫描磁共振成像对肝血管瘤的诊断价值。材料和方法:34例肝血管瘤病人行常规MRT1WI、T2WI横断面扫描。经肘静脉手推团注0.1mmol/kg体重Gd-DTPA后,再推入10ml生理盐水冲洗后(推入时间5~6s)行射频毁坏傅立叶采集稳态技术T1WI动态增强扫描及延迟增强扫描,分析病灶及邻近肝实质增强。结果:共发现肝血管瘤病灶67个。动态增强见46个病灶呈边缘不连续样的结节样强化,21个病灶呈周边不规则强化或迅速强化充填;5个病灶动态增强早期见引流静脉强化,14个瘤周肝实质强化。延迟增强扫描见53个病灶完全充填强化,14个病灶显示斑片状或裂隙状的低信号未充填区。结论:在磁共振成像检查中,动态增强扫描能够显示肝血管瘤及邻近实质强化方式,延迟增强显示病灶的充填程度,两者结合更有利于肝血管瘤的诊断。     

SPIO与Gd-DTPA增强对裸鼠肾癌移植瘤显影价值对照研究

目的:比较SPIO与Gd-DTPA增强对裸鼠肾癌移植瘤显影价值.方法:种植人肾癌Ketr-3细胞的雄性裸鼠14只,随机分为2组:SPIO组7只,Gd-DTPA组7只.SPIO组先行T_2 WI平扫,后快速注入Reso-vist,注药后即时、10min重复T_2WI序列.Gd-DTPA组先行T_1WI平扫,后快速注入Gd-DTPA,注药后即时、10rain重复T_1WI序列.扫描结束分别测量两组移植瘤增强前后的信号强度及计算相对增强率.结果:SPIO组注入Resovist后,即时移植瘤T_2信号强度(SI)开始下降,10min后T_2SI逐渐回复.Gd-DTPA组注入Gd-DTPA后,即时移植瘤T_1SI明显增加,10min后T_1SI亦维持于较高水平.结论:Gd-DTPA对于肾癌移植瘤的诊断有着较长的强化时间窗,且强化效果较SPIO更明显.     

The dynamic magnetic resonance study of focal liver lesions by FLASH sequences with bolus intravenous gadolinium-DTPA]

Thirty-five patients with hepatic hemangioma (n = 12), metastasis (n = 10), hepatocellular carcinoma (HCC) (n = 10) and focal nodular hyperplasia (n = 3) were examined with the fast low-angle shot (FLASH) technique and an intravenous bolus injection of Gd-DTPA. In order to differentiate the lesions, the following criteria were used: a) pre Gd-DTPA intensity of lesions; b) post Gd-DTPA patterns of contrast enhancement. On the basis of these criteria, an unquestionable differential diagnosis could be made. Hemangiomas were characterized by an hypointense mass before Gd-DTPA, by peripheral contrast enhancement and by subsequent continuous hyperintense fill-in; thus, hemangiomas were visualized as hyperintense lesion during the late phase. Before contrast administration hypovascular metastases appeared as hypointense; they were characterized by delayed uptake of contrast agent. HCCs were hyperintense lesions before contrast administrations; then, quick contrast enhancement and rapid decrease in signal intensity were observed with visualization of a hyperintense ring due to the capsule. Finally, focal nodular hyperplasia appeared isointense or hypointense relative to normal liver on precontrast scans; the lesions were enhanced transiently with subsequent quick dismission of contrast agent. This initial experience suggests dynamic contrast-enhanced MR imaging as an effective method to improve the differential diagnosis among hepatic tumors when precontrast T2-weighted images are equivocal.     

垂体微腺瘤不同增强方式MRI的诊断价值

目的 :探讨注射对比剂后不同增强方式对垂体微腺瘤的诊断价值。方法 :对 5 6例垂体微腺瘤患者先行矢状面及冠状面T1WI和T2 WI扫描 ,然后行GD DTPA冠状面T1WI动态增强扫描和常规延迟增强扫描 ,3 0min后再行冠状面T1WI延迟增强扫描。结果 :5 6例微腺瘤中平扫显示 13例 ,动态增强显示 5 5例 ,常规延迟增强显示 48例 ,延迟增强显示 3 3例。其中动态增强清楚显示 47例 ,常规延迟增强清楚显示 2 6例 ,延迟增强清楚显示 14例 ,三者检出率比较 ,差异有统计学意义。结论 :动态增强扫描与常规延迟增强可明显提高垂体微腺瘤的检出率 ,具有较高诊断价值 ,延迟增强扫描检出率较低 ,不适宜常规应用。     

Contrast-enhanced 3D-TOF MRA of peripheral vessels: Intravascular versus extracellular MR contrast media

MR contrast media have been used to improve MR angiography (MRA). Their effect has been particularly beneficial for extracranial MRA. This study evaluated the efficacy of a new formulation of ultrasmall super-paramagnetic iron oxide particles (USPIO) on three-dimensional (3D) time of flight (TOF) MRA in the pelvis and lower limb circulation. Each of six dogs received 3 mg/kg of USPIO and .2 mmol/kg of gadolinium-dieth-ylenetriamine pentaacetic acid (Gd-DTPA) bis-meth-ylamide (BMA) by intravenous infusion on separate examinations. Precontrast and postcontrast 3D-TOF MRA images of the lower extremities were acquired over the course of 45 minutes postinjection. Signal intensity (SI) was measured on axial views along the external iliac, femoral, and popliteal arteries. USPIO provided clear demarcation of the major primary, secondary, and tertiary vessels and the improved contrast-to-noise ratio (CNR) was maintained for 45 minutes. Gd-DTPA-BMA provided less signal enhancement than USPIO. The increase in CNR with this agent had significantly declined by 15 minutes after injection. The major vessels could no longer be visualized at 30 and 45 minutes after injection of Gd-DTPA-BMA. This study demonstrates the efficacy of USPIO as a contrast medium for 3D-TOF MRA. It was concluded that USPIO provided effective and persistent enhancement of the peripheral vessels.     

多层动态增强MRI技术对肝血管瘤诊断的评价

目的:研究射频毁坏傅立叶采集稳态技术(RFFAST)的动态增强及延迟增强扫描MRI对肝血管瘤的诊断价值。方法:34例肝血管瘤患者行常规MRT1WI和T2WI横断面扫描。经肘静脉团注GdDTPA0.1mmol/kg,后推入10ml生理盐水冲洗(推入时间5～6s),再行射频毁坏傅立叶采集稳态技术T1WI动态增强扫描及延迟增强扫描,分析病灶及邻近肝实质增强。结果:共发现肝血管瘤病灶67个,T1WI上呈低信号,T2WI上呈高信号;动态增强显示46个病灶呈边缘不连续的结节样强化,21个病灶呈周边不规则强化或迅速强化充填;5个病灶动态增强早期见引流静脉较早强化,14个瘤周肝实质强化。结论:磁共振成像检查中,射频毁坏傅立叶采集稳态技术T1WI动态增强扫描能够显示肝血管瘤及邻近实质强化方式,与其他成像序列结合更有利于肝血管瘤的诊断。