口服磁共振造影剂（D98A）用于上消化道检查的临床应用研究

目的：探讨新型口服超顺磁性磁共振造影剂－D98A,在上消化道检查中的应用价值。方法：采用扫描前口服D98A的22例受检查与10例服用等量纯净水健康志愿者,年龄21－55岁,使用不同场强的MR机,行上消化道MR检查,对图像进行影像学分析和对照研究。结果：22例受检者服用D98A后,上消化道充盈率达100％,在各序列扫描中,上消化道均呈阴性对比状态。腹膜后器官边界显示率,由服用前的25％提高到95％。消化道病变情况及毗邻关系比对照组提高数倍。结论：D98A安全性好,性能稳定,成像浓度范围宽,具有优良的胃肠道阴性对比效果,是MR检查上消化道理想的造影剂。     

口服超顺磁性氧化铁在MRCP中的应用

目的：研究超顺磁性氧化铁(SPIO)作为胃肠道阴性对比剂在改善磁共根胰胆管成像(MRCP)质量的应用。方法：30例受检者口服2mmol/Fe／1的SPIO液100m1后进行TSE MRCP检查，采用西门子1．5T MRI扫描机，服药前后常规行单层和多层扫描，原始图像经工作站处理后，采用最大信号强度投影技术重建获得新图像。结果：口服SPIO溶液可以完全抑制胃及十二指肠内液体信号，排除其干扰，使MRCP时胰胆管显影更加清晰。结论：口服SPIO，行MRCP检查，能抑制胃肠道内液体信号，使胰胆管显影更加清晰，特别是在TSEMRCP成像时效果更佳。     

胃肠道阴性对比剂在磁共振胰胆管成像中的应用

目的：评价马根维显（Gd—DTPA）溶液作为胃肠道阴性对比剂对改善磁共振胰胆管成像（MRCP）质量的价值。方法：对30例疑有胰、胆管系统疾病的患者口服对比剂前后分别行常规腹部MR和MRCP检查,采用相同的扫描参数及定位。结果：所有病例口服对比剂后MRCP扫描,胃及十二指肠内液体高信号均较前有明显下降,图像质量明显提高。口服稀释的Gd—DTPA溶液前后,MRCP检查胆总管、胰管及胆囊结构的显示效果具有显著性意义（P〈0．05）。结论：口服稀释的Gd—DTPA溶液是一种安全有效降低胃肠道液体高信号强度、改善MRCP图像质量的方法。     

胃肠道阴性对比剂在磁共振胰胆管成像中的应用研究

目的　研究胃肠道阴性对比剂在改善磁共振胰胆管成像 (MRCP)质量的应用。方法　体外实验 :将马根维显 (Gd -DTPA)和欧乃影注射液分别用温开水稀释为不同浓度制剂盛入 10ml注射器内 ,以温开水作空白对照 ,然后行MRCP扫描 ,以获取对比剂最佳稀释倍数。临床实验 :对 3 9例临床疑胰胆管系统疾病申请MRCP检查患者行口服稀释 3 0 0倍马根维显溶液前后常规腹部MR和MRCP检查 ,扫描参数及定位完全相同。结果　体外实验 :稀释 3 0 0倍的马根维显溶液和稀释 2 0 0倍的欧乃影溶液为最佳浓度。临床实验 :所有病例口服稀释 3 0 0倍的马根维显溶液后 ,胃与十二指肠内的液体高信号被明显抑制 ,MRCP胆管显示效果对比在服对比剂前后具有显著性意义 (P <0 .0 5 )。结论　口服稀释 3 0 0倍的马根维显溶液作为胃肠道阴性对比剂可有效地改善MRCP图像的质量。     

不同对比剂用于螺旋CT胃部三维成像的对照研究

目的合理选择螺旋CT胃部三维成像口服对比剂。方法41例胃部疾病患者进行了49次胃部CT专一检查,将使用的口服对比剂随机分为3组空气对比剂组17例;脂肪乳剂对比剂组7例;阳性对比剂组25例。经螺旋CT容积扫描后分别使用CT仿真内窥镜（CTVE）、表面遮盖法（SSD）、透明法（RaySum）及多层面重建（MPR）技术进行胃部三维成像,所获得的图像与胃镜和（或）胃肠道钡餐检查（GI）进行对照,比较不同对比剂对三维重建图像的影响。结果脂肪乳剂组、空气对比剂组及阳性对比剂组的病灶检出率分别为42.9%(3/7)、80.0%(20/25)及100.0%(30/30),使用不同对比剂与病灶检出率有关,前两者与后者之间的差异均有显著性意义（χ2分别为19.22和6.60,P值均＜0.05）;不同的对比剂对病灶细节的显示也有很大的影响,以阳性对比剂最好（χ2=17.04,P＜0.01）。结论口服对比剂的选择在胃部螺旋CT三维重建技术中有重要作用,以阳性对比剂为优。     

肝脏局灶性结节增生(FNH)的影像诊断

本文回顾分析了8例FNH的平扫和动态增强CT和MR表现,并复习文献,旨在提高对本病的诊断准确性。1材料与方法1.1一般资料收集我院经临床、病理证实的8例FNH,其中男5例,女3例,年龄22~58岁,平均38岁。4例无任何症状,2例因上腹部隐痛而行影像学检查,1例因肺部病变行胸部CT扫描时偶然发现肝Ⅷ段结节灶。所有病例无肝炎病史,AFP阴性,其它各种肿瘤标志物检查均为阴性。1.2方法7例使用SomatomPlus 4螺旋CT机行CT平扫和动脉期(注射对比剂后25~30s)、门脉期(注射对比剂后50~60s)、延迟期扫描(注射对比剂后3~4min),2例延迟15min扫描。常规层厚5~…     

新型口服磁石MRI对比剂D98A的临床试用

目的评价一种新近由磁石为原料研制成功的超顺磁性口服磁共振对比剂D98A在腹部MRI诊断中的应用价值。方法通过不同场强的MR机，对80例受检者进行了平扫和服用D98A量500～1000ml的MRI检查，扫描序列包括T1WI、T2WI和脂肪抑制，观察该对比剂的对比效果、分布情况及对腹腔脏器轮廓的勾画及副反应。结果D98A对比剂易于受检者接受、安全性好、性能稳定、胃肠道充盈良好，在各种扫描序列下胃肠道均呈低信号对比状态，腹部脏器的勾画较平扫明显提高，使用D98A前后胃肠道显示率由平均约10％，提高到约89％，。受检者均未出现副反应。结论D98A安全有效，有利于腹腔内实质脏器的勾画，可提高胃肠道和腹腔内病变诊断的准确性。     

钆类和氧化铁类MR对比剂在诊断急性脑梗塞中的应用

近十年MR对比剂的发展迅猛,开发了多种顺磁性和超顺磁性对比剂。对比剂的应用进一步拓宽了影像学技术的检查范围的广度和深度,尤其是对超急性期缺血性脑梗塞诊断。本文主要简述与缺血性脑梗塞MR诊断有关的钆类和超顺磁性氧化铁类对比剂的进展概况,和不同MR检查方法诊断缺血性脑梗塞的原理。     

磁共振成像2D-FIESTA序列对婴幼儿胆道病变的诊断价值

目的评价磁共振成像2D-FIESTA序列对婴幼儿胆道病变的诊断价值。方法8例婴幼儿患者行MR检查胆道系统。患儿口服水合氯醛或静注安定镇静。行轴位、冠状和矢状2D-FIESTA扫描。不需屏气。不使用MR对比剂。在ADW工作站上以最大强度投影(M IP)和多平面重建(MPR)方式重建图像。结果3例肝移植术后、2例胆总管囊肿、1例胆胰管合流异常患儿的MR I表现均经手术证实,2例正常婴幼儿经随访证实。MR I的2D-FIESTA序列可清晰显示患儿的肝外胆管及门静脉、肝静脉和下腔静脉,肝动脉显示欠清晰。结论MR I的2D-FIESTA序列可在自由呼吸、不使用对比剂的条件下准确显示婴幼儿的胆道系统病变。     

口服枸橼酸铁铵在梗阻性黄疸MRCP检查中的应用价值评估

目的评价采用枸橼酸铁铵作为胃肠道口服阴性对比剂对提高梗阻性黄疸患者磁共振胰胆管成像(MRCP)检查质量的作用。方法对50例临床怀疑梗阻性黄疸的患者行MRCP检查,将患者随机分为2组:试验组25例患者,在检查前30min时口服枸橼酸铁铵冲剂;对照组25例患者,不服用任何对比剂。观察患者对口服对比剂的耐受性;对所有患者进行冠状位厚层的半傅立叶单次激励快速自旋回波序列(HASTE)和呼吸触发的3D快速自旋回波序列(RT-3D-TSE)扫描。由2位放射科医师单盲阅片,对2组患者MRCP图像的对比效果和图像质量作评估和分级。结果所有患者对枸橼酸铁铵溶液都有很好的耐受性。口服枸橼酸铁铵溶液后所有试验组MRCP图像上的胃肠道高信号都有很大程度的抑制,对比效果和图像质量有明显改善,胆道解剖结构显示的清晰性明显提高。结论口服枸橼酸铁铵溶液作为安全的胃肠道阴性对比剂在梗阻性黄疸患者的MRCP检查中可以有效降低胃肠道高信号所造成的影响及假象,改善胆道系统的显示情况,便于诊断。     

Appearance of Pantopaque on MR images

Pantopaque was shown to be both a radiographic and magnetic resonance (MR) contrast agent in two patients with suspected cord abnormalities who underwent MR examination following myelography. The Pantopaque appeared as a linear band of high signal intensity along the dependent portion of the spinal canal on MR images obtained with a repetition time of 500 msec and an echo time of 30 msec. MR images of two dogs--one injected with Pantopaque in the cervical subarachnoid space and the other with Amipaque--confirmed that the high signal arose from the Pantopaque. This high signal intensity is due to Pantopaque's short T1 relaxation time. Although Pantopaque will probably not be used as an MR contrast agent, it is important to recognize this property so that its high signal is not mistaken for fat or hemorrhage in the subarachnoid space on MR images.     

硫酸钡混悬剂用作MRI胃肠腔造影剂的研究——Ⅱ、临床试用观察

目的：通过临床志愿者试用观察自行研制的MRI胃肠腔造影用硫酸钡混悬液的安全性和有效性．材料和方法：使用自制MRI胃肠腔造影用硫酸钡混悬液对：100例次的腹部MRI检查进行了胃肠造影，观察该混悬液的造影效果，分布情况，对腹部脏器轮廓显示的影响及副反应。结果：临床试用表明自制硫酸钡混悬液以180%（W／V)浓度口服后使胃肠腔显示明确低信号．有利于腹部器官轮廓的显示，提高了腹部MRI诊断价值，口服后所有病人未出现需对症处理的副反应。结论：我们自行研制的MRI胃肠腔造影用硫酸钡混悬液安全有效，适于临床使用。     

口服磁共振造影剂枸橼酸铁铵的临床应用

目的 探讨枸橼酸铁铵（ferric ammonium citrate，FAC）作为一种口服阴性造影剂在改善磁共振图像质量的应用。方法 共收集患者50例，其中20例磁共振胰胆管水成像（MRCP），20例泌尿系统水成像（MRU），10例为盆腔成像。口服枸橼酸铁铵（3g：600mg／包）前、后以相同采集参数行磁共振成像，均采用GE 1．5T磁共振机。并对口服枸橼酸铁铵前、后的图像质量进行比较。结果 口服枸橼酸铁铵15min后行MRCP成像，可有效消除胃、十二指肠内液体对图像的干扰。40min到lh左右内分2次口服枸橼酸铁铵后行MRU和盆腔成像，可消除部分空肠、回肠、结肠内液体对图像的干扰。结论 枸橼酸铁铵作为一种口服阴性造影剂开始逐步应用于临床工作中，可以改善MRCP、MRU及盆腔的图像质量。     

A multicenter clinical trial of gadolite oral suspension as a contrast agent for MRI

The purpose of this study was to assess the effectiveness and safety of Gadolite Oral Suspension as a gastrointestinal (GI) contrast agent for MRI in a phase II and two phase III multicenter clinical trials. Gadolite was administered to 306 patients with known or suspected abdominal and/or pelvic disease. MRI with T1- and T2-weighted sequences was performed before and after ingestion. Efficacy was evaluated by having two masked readers rate the certainty of their MR diagnosis (0 = uncertain, 1 = probable, 2 = definite) on randomly presented pre- and post-Gadolite Oral Suspension enhanced images. Principal investigators also evaluated the images and established the final diagnosis. Vital signs, clinical chemistries, and adverse events were documented. Blood and urine samples were analyzed for gadolinium content to determine whether Gadolite Oral Suspension was absorbed systemically. Certainty in MR diagnosis increased significantly (P < .001) for both blinded readers between pre- and post-Gadolite images (.49–1.18 for reader 1; .46–1.53 for reader 2). Sensitivity, specificity, and accuracy also increased for both masked readers. No gadolinium was detected in blood or urine samples. There were no serious adverse events and no apparent drug-related trends in mean vital signs or laboratory values. Gadolite is a highly effective, safe, and well tolerated contrast agent for clinical use with MRI.     

MR imaging of the stomach: potential use for mangafodipir trisodium--a study in swine

PURPOSE: To evaluate mangafodipir trisodium as a potential contrast agent at magnetic resonance (MR) imaging of the stomach. MATERIALS AND METHODS: Mangafodipir trisodium was injected intravenously into three swine at a dose of 5 micromol per kilogram of body weight. For comparison, gadopentetate dimeglumine was injected into three other swine at a dose of 0.1 mmol per kilogram of body weight. T1-weighted three-dimensional MR images were acquired in all six swine at 1.5 T before and approximately 10, 15, 20, 25, 30, and 40 minutes after contrast material administration. Extracted stomach specimens were imaged at 3.0 T. In vivo and ex vivo images were evaluated visually and quantitatively for contrast enhancement of the stomach, and in vivo images were evaluated for the presence of reflux from the duodenum. RESULTS: Mangafodipir trisodium produced prolonged and selective enhancement of the inner surface of the stomach, in contrast to the more general enhancement seen with gadopentetate dimeglumine, and reflux from the duodenum could not account for this selective enhancement. Ex vivo images confirmed that T1 enhancement in the stomach wall with mangafodipir trisodium was limited to the inner surface. Gadopentetate dimeglumine did not produce selective enhancement of the inner surface of the stomach. CONCLUSION: Mangafodipir trisodium preferentially enhances the inner surface of the stomach on MR images acquired in swine and, therefore, may have potential for use as a contrast agent at MR imaging of the human stomach.     

Optimization of dosage and exam technique in the use of oral contrast media in magnetic resonance]

PURPOSE: Aim of our study was to optimize the dose, scan delay and sequences for use in MR studies with an oral contrast agent (FerriSeltz, Bracco, Milan, Italy) to obtain positive or negative contrast enhancement in the bowel lumen. MATERIAL AND METHODS: In vitro: 10 mL vials with increasing concentrations (10-100 mg/mL) of the agent, containing 200 mg ferric ammonium citrate/g, were studied with a 1.5 T magnet (Philips NT, The Netherlands), by acquiring T2-weighted STIR and TSE and T1-weighted TFE sequences. Signal intensity was compared by using a ROI. In vivo: 16 volunteers were examined with the same sequences at 20 minutes and 2 hours after the oral administration of 6-27 g of the product diluted in 600 mL water. Images were analyzed by two radiologists and scored on a 4-point scale based on signal intensity; results were compared with Student's "t"-test. RESULTS: In vitro: MR signal was always hyperintense on T1-weighted images, as well as on T2-weighted TSE and SPIR images at concentrations lower than 45 mg/mL. Hypointense signal was seen on T2-weighted TSE and SPIR images at higher concentrations and on STIR sequences at 10-20 mg/mL concentrations. In vivo: the bowel exhibited positive enhancement on T1-weighted TFE and T2-weighted TSE and SPIR images 20 minutes after contrast agent administration at concentrations lower than 45 mg/mL. At 2 hours, bowel loops were hypointense on T2-weighted TSE and SPIR images at 15-20 mg/mL concentrations. STIR images showed hypointense bowel loops at both 20 minutes and 2 hours after 10-20 mg/mL contrast agent administration. Quantitative analysis showed a statistically significant superiority (p < .05) of T2-weighted STIR images in providing negative opacification of the bowel lumen. CONCLUSIONS: Ferric ammonium citrate, being a positive or negative contrast agent according to its dilution, permits to tailor the dose to optimize bowel lumen opacification.     

Blueberry juice used per os in upper abdominal MR imaging: composition and initial clinical data

The aim of this study was to evaluate the use of a commercially available blueberry juice (BJ) both as a positive and negative oral contrast agent and to present the exact contents of paramagnetic ions. The concentration of Mn and Fe were determined in tinned myrtilles in syrup (atomic absorption). Nine healthy volunteers and 12 patients (age range 20–65 years) were examined using a 1-T MR scanner before and after per os administration of 430 ml of BJ. A qualitative analysis of signal alterations in the stomach, duodenum, and proximal small intestine was performed. In addition, a quantitative analysis was assessed in terms of signal-to-noise ratio calculation. The mean concentration ( ×± SD) of the ions found in the content of the three cans were 3.3 ± 0.4 μg/g for iron and 20.6 ± 2.6 μg/g for manganese. Based on the qualitative evaluation, signal alteration on T1-weighted images after administration of BJ was statistically significant in the stomach and duodenum, but not in the proximal small bowel. Signal alteration on T2-weighted images was not statistically significant in any part of the gastrointestinal tract. The quantitative analysis of the T1- and T2 shortening showed that BJ is efficient with only T1-weighted sequences, and this applied to the stomach, duodenum, and proximal small bowel. Blueberry juice can be used as an oral contrast agent in upper abdominal MR for T1-weighted imaging. Received: 7 September 1999; Revised: 29 November 1999; Accepted: 16 February 2000     

黑腔MR胃肠水成像的临床应用

目的:探讨黑腔MR胃肠水成像的临床应用.方法:38例患者(上消化道17例、结肠21例)采用低张力、口服或灌注水作为胃肠对比剂,作MR黑腔水成像.适应证:内窥镜或其它影像检查后需进一步诊断者;内窥镜检查不能完成者(失败).MR扫描用多方位采集,屏气T1WI平扫及增强,依需要加作FSE T2WI.结果:38例患者检查均达到诊断要求,其中除4例阴性外,胃癌7例,胃间质瘤3例,十二指肠癌4例,结肠癌9例,炎性胃肠病5例(过敏性肠病、炎性肠病),阑尾周围脓肿2例,回盲部淋巴肉瘤、大网膜间质瘤、胃周转移瘤(源于胰腺)、胃曼内特尔氏病各1例.结论:黑腔MR水成像作为无创性常规检查,用于胃肠病诊断是一种有价值的方法.