Gd-DTPA增强在MRCP图像质量控制中的作用及临床应用

目的:评价静脉注射钆喷酸葡胺(Gd-DTPA)增强在抑制影响磁共振胰胆管成像(MRCP)图像质量的腹部小血管高信号中的作用。方法:选择临床可疑有胰胆管病变并准备行MRI检查患者31例做为研究对象,所有病人分别行Gd-DTPA增强前及增强后1~5min、5~10min1、0~15min MRCP扫描,测量并比较增强前后MRCP图像上肝脏、胰腺、胆总管、胰管的信噪比(SNR)以及胆总管与肝实质、胰管与胰腺的信号强度比(SIR)。结果:静脉注射Gd-DTPA增强后1~5min、5~10min及10~15min图像上胰胆管树各解剖结构显示情况和平均等级分数均无统计学差异(P>0.05);Gd-DTPA增强后的MRCP图像胰胆管树解剖结构显示情况和平均等级分数与增强前比较有显著性差异(P=0.000)。Gd-DTPA增强后MRCP图像上来自肠系膜上静脉及其分支与胰管重叠的血管信号、左右门静脉及其分支与肝内二级胆管重叠的血管信号被明显抑制,肝脏及胰腺信号强度降低,胰胆管树对比度提高,肝内2级胆管、肝总管、胆总管和胰管显示更加清楚。结论:MRCP成像中,静脉注射Gd-DTPA增强能抑制来自左右门静脉和肠系膜上静脉及其分支等血管的高信号,提高胰胆管树的对比度,明显改善MRCP图像质量。     

MRI增强扫描对脑转移瘤的诊断价值

目的 总结磁共振增强扫描在脑转移瘤诊断中的重要价值。方法 脑转移瘤32例，均经病理和临床证实，全部病例均做了Gd-DTPA增强前后扫描。结果 脑转移瘤单发15例，多发17例，发生在幕上26例，幕下6例，幕上幕下并存4例。病灶最大径在0．5cm～6cm，平均2．4cm。发现病灶数：T1WI40个，T2WI56个，增强后发现116个。结论 增强扫描发现的脑转移瘤病灶明显多于平扫，并且能分清病灶与瘤周水肿的界限，从而明确其发生的部位、数目、形态、和大小，结合临床和影像学特征，容易作出正确诊断。     

2种磁共振对比剂动态增强扫描对肝内结节的鉴别诊断价值

目的：探讨钆喷酸葡胺(Gd-DTPA)及钆塞酸二钠(Gd-EOB-DTPA)的磁共振动态增强扫描对肝脏结节的鉴别诊断价值。方法回顾性分析60例经 Gd-DTPA 及 Gd-EOB-DTPA 增强的肝内结节磁共振平扫、多时相动态增强扫描图像。结果所有入组病例经 Gd-DTPA 动态增强扫描后,19例患者诊断为原发性肝细胞癌,并经病理证实;8例确诊为肝转移瘤;18例诊断为肝内良性结节,随访3~6个月结节大小无明显变化。15例鉴别诊断困难的患者行 Gd-EOB-DTPA 多时相动态增强扫描,4例动脉期明显强化,门脉期强化程度迅速下降,平衡期轻度强化,肝特异性期与正常肝实质比较呈等信号,后证实为肝腺瘤;7例动脉期轻到中度强化,门脉期强化程度下降,平衡期强化不明显,肝特异性期与正常肝实质比较呈低信号,经随访或病理确诊为肝细胞癌;3例动脉期表现为轻度强化,门脉期及平衡期略强化,肝特异性期与正常肝实质比较呈低信号,根据其病史诊断为转移瘤;1例动脉期病变周边明显强化,门脉期强化程度迅速下降,平衡期轻度强化,肝特异性期与正常肝实质比较呈等信号,病变中心始终呈低信号,经复查诊断为肝良性病变。结论Gd-DTPA 动态增强 MRI 扫描对诊断肝内结节性病灶具有重要作用,Gd-EOB-DTPA 在鉴别结节的良恶性方面具有较大优势。     

MRI 增强后扩散加权成像鉴别乳腺良恶性肿瘤临床应用研究

目的：评估乳腺疾病患者中钆对比剂对 MRI 扩散加权成像(DWI)和病变的表观扩散系数(ADC)是否有显著性影响,分析增强前后 ADC 值在乳腺良恶性病变鉴别中的价值。方法收集本院行乳腺 MRI 检查的35例患者共计38个病灶,所有病灶均经病理证实。笔者对比了增强前后正常乳腺组织及病灶的信噪比(SNR)和对比噪声比(CNR),以及病灶增强前后的 ADC 值。结果(1)增强前后 DWI 的 SNR 及 CNR 无统计学差异;(2)恶性病灶增强前后的 ADC 值存在统计学差异,增强前后 ADC 值平均降幅11.6%;良性病灶增强前后的 ADC 值无统计学差异。结论增强后 ADC 值能够更好地反映乳腺病变的恶性潜能。     

钆布醇在心肌梗死伴心力衰竭患者磁共振延迟增强成像中的应用

目的 比较单倍剂量钆布醇和单倍剂量钆喷酸葡胺在心肌梗死伴心力衰竭患者心脏磁共振延迟增强成像中显示梗死心肌的差异.方法 前瞻性纳入42 例有心肌梗死病史合并心力衰竭患者行心脏磁共振延迟增强成像扫描,根据对比剂类型将患者随机分为A组(钆喷酸葡胺)和B组(钆布醇).最终40 例患者的心脏磁共振延迟增强图像用于数据分析:A组20 例,B组20 例.延迟增强图像分别于注射对比剂后5～8 min、9～12 min及13～16 min时完成.比较两组对比剂之间左心室血池的信噪比(SNRLV)、梗死心肌的信噪比(SNRIM)、梗死心肌和正常心肌之间的对比噪声比(CNRIM-RM)及梗死心肌和左心室血池之间的对比噪声比(CNRIM-LV);比较同一组对比剂在三个时间段内左心室梗死心肌体积的差异.结果 5～8min时,两组对比剂在SNRIM、SNRLV、CNRIM-RM和CNRIM-LV之间的差异均无统计学意义(P>0.05),且SNRIM、SNRLV在同一组对比剂内无显著差异(P>0.05);此时无法准确测量左心室梗死心肌体积.9～12 min和13～16 min时,两组对比剂的SNRIM均显著高于SNRLV(P<0.05),B组的SNRIM、SNRLV、CNRIM-RM和CNRIM-LV均显著高于A组(P<0.05).在这两个时间段内,左心室梗死心肌体积在同一组对比剂内差异无统计学意义(P>0.05).结论 由心肌梗死所致心力衰竭患者在延迟时间为 9～12 min、13～16 min行心脏磁共振延迟增强扫描时,单倍剂量钆布醇较单倍剂量钆喷酸葡胺可更好地显示、评估梗死心肌的程度.     

单倍剂量钆布醇与双倍剂量钆喷酸葡胺在心力衰竭患者心脏MR增强评估心肌纤维化与心肌梗死中的对比研究

【摘要】目的：采用MR延迟增强、T1-mapping技术探讨单倍剂量钆布醇和双倍剂量钆喷酸葡胺在心力衰竭患者心肌纤维化与心肌梗死评估中的价值。方法：54例使用钆喷酸葡胺和44例使用钆布醇增强的心力衰竭患者的心脏MR图像用于数据分析。在MR延迟增强、增强后T1-mapping图像上测量左心室血池、正常心肌、延迟强化心肌的信号强度及T1值,计算左心室血池的信噪比（SNRLV）、延迟强化心肌的信噪比（SNRhyper）、延迟强化心肌和正常心肌之间的对比噪声比（CNRhyper-remote）及T1差值（△T1hyper-remote）、延迟强化心肌和左心室血池之间的对比噪声比(CNRhyper-LV）及T1差值（△T1hyper-LV)。结果：钆布醇SNRLV低于钆喷酸葡胺（P<0.001）,钆布醇CNRhyper-LV、T1LV和△T1hyper-LV均高于钆喷酸葡胺(P<0.001),且差异均有统计学意义;但两种对比剂的SNRhyper、CNRhyper-remote、T1hyper和△T1hyper-remote之间差异无统计学意义。结论：心力衰竭患者行心脏MR延迟增强检查时,使用单倍剂量钆布醇可比双倍剂量钆喷酸葡胺更好地评估心肌纤维化与心肌梗死情况。     

计算机辅助分析在MRI乳腺成像中的诊断价值

目的：目的：计算机辅助分析应用于MRI乳腺成像的临床应用价值目前仍有争议。本研究是评价彩色编码计算机辅助诊断系统帮助不同经验水平的放射学者的价值。方法：前瞻性研究48例病人包括88个病变（43个恶性,45个良性）,所有病人均行1．5T磁共振仪扫描并根据体重静脉注射0．1mmol／kg马根维显溶液。三位读片者在没有临床数据的情况下独立分析图像,第1、2位放射学者相比与第三位放射学者对于MRI乳腺成像的解释分析有更多的经验。     

钆塞酸二钠和钆喷酸葡胺肝脏多期动态增强呼吸伪影对比研究

目的:比较静脉注射钆塞酸二钠(Gd-EOB-DTPA)和钆喷酸葡胺(Gd-DTPA)的动脉期呼吸伪影,寻求减少Gd-EOB-DTPA动脉期呼吸伪影的可能方案.方法:搜集在1年内行Gd-EOB-DTPA和Gd-DTPA磁共振动态增强扫描的患者75例,由两位有经验的磁共振医师采用盲法对两种对比剂扫描方案的动脉期、门脉期及延迟期图像采用5分法评分,以≤3分定义为中重度伪影.两种对比剂扫描方案的呼吸伪影比较采用Wilcoxon秩和检验和配对卡方检验.结果:Gd-EOB-DTPA组发生动脉晚期呼吸伪影的比例明显高于Gd-DTPA组(分别为49.3％和6.7％,Z=-5.058,P＜0.001),其中中重度伪影的比例亦明显高于Gd-DTPA(分别为33.33％和2.67％,x2=21.04,P＜0.001);而Gd-EOB-DT-PA组动脉早期出现呼吸伪影和中重度呼吸伪影的比例与Gd-DTPA组差异无统计学意义(Z=-1.513,P=0.130;x2=0.25,P=0.625).结论:静脉注射Gd-EOB-DTPA较Gd-DTPA更易引起动脉期伪影,减少单期屏气时间和采用动脉期监测技术可能提高Gd-EOB-DTPA动脉期采集的图像质量.     

莫迪司MRI增强扫描在周围性胆管细胞癌及肝脓肿鉴别诊断中应用

【摘要】目的：探讨莫迪司MRI增强扫描在周围性胆管细胞癌及肝脓肿鉴别诊断中的价值，以减少误诊。方法：回顾性搜集经病理证实的22例肝脓肿及21例周围性胆管细胞癌，所有病例均行莫迪司MRI平扫和增强扫描，对比分析2组MRI表现差异。结果：周围性胆管细胞癌与肝脓肿在病灶形态、信号均匀性、边缘方面差异无统计学意义（P＞0.05）；2组病灶增强扫描多为渐进性强化，且DWI呈高信号，差异无统计学意义（P＞0.05）；2组病灶伴随征象（邻近胆管扩张、胆管结石、异常灌注及肝包膜回缩）发生率差异无统计学意义（P＞0.05）；肝胆期，周围性胆管细胞癌外周部呈相对低信号18例（18/21），肝脓肿外周部呈均高信号（22/22），二者比较有统计学意义（P＜0.05）。结论：肝胆期，周围性胆管细胞癌外周部强化减低，而肝脓肿外周部呈持续强化，具有重要的诊断价值。     

健康人停经前乳腺动态增强MRI表现

目的评价健康人停经前乳腺动态增强MRI表现,探讨其鉴别健康人停经前乳腺实质内出现的增强灶和良恶性病变的能力.材料和方法对18例健康自愿者和40例乳腺病变患者行3D动态增强MRI检查.分析实质增强灶数量、形态、早期增强率和时间-信号强度曲线形态并与良恶性病变比较.结果55.6%的自愿者乳腺内出现实质增强灶.其表现为片状或结节状,边缘模糊、不规则或光滑,早期增强率小于良恶性病变,与腺体无明显差异,时间-信号强度曲线均为单相型,明显不同于恶性病变.结论停经前妇女乳腺内出现对比增强灶是一种正常表现,时间-信号强度曲线是鉴别实质增强灶与恶性病变的很好方法.     

Gd-BOPTA增强MRI对小肝癌的诊断价值

目的　比较Gd BOPTA增强MRI与MRI平扫、Gd DTPA动态增强MRI在诊断小肝癌 (SHCC)方面的差异 ,进一步提高小肝癌检出率和诊断准确性并观察其不良反应。资料与方法　手术或穿刺病理证实为SHCC患者 2 5例。采用GESigna 1.5T磁共振扫描仪。行SE序列T1WI、FSE序列T2 WI及Gd DTPA快速动态增强多期扫描。Gd BOPTA增强扫描亦采用静脉团注快速动态增强扫描 (同Gd DTPA) ,并在团注后 15min、6 0min行SE序列T1WI和FMPSPGR序列T1WI扫描各 1次。观察MRI平扫、Gd DTPA快速动态增强和Gd BOPTA增强扫描及延迟扫描对病灶的检出率、包膜显示情况以及病灶的强化特征并行统计学分析。观察其不良反应。结果　 2 5例患者共发现病灶4 2个。对SHCC病灶的检出率 ,MRI平扫为 6 9.0 5 % ,Gd DTPA增强为 85 .71% ,Gd BOPTA增强 (动态 延迟 )为95 .2 4 % ,和Gd DTPA增强之间无统计学差异 ,和MRI平扫有统计学意义。病理检查发现 30个病灶有包膜。Gd BOPTA增强对SHCC包膜的显示 ...     

A double-blind,comparative study of gadodiamide injection and gadopentetate dimeglumine in MRI of the central nervous system

Summary Seventy-nine patients with known or suspected central nervous system lesions were studied with MRI in a phase III double-blind study. Forty were given gadopentetate dimeglumine (Gd-DTPA) and 39 gadodiamide injection (Gd-DTPA BMA), a new low-osmolar nonionic contrast enhancing medium. The dosage was 0.1 mmol/kg body weight, corresponding to 0.2 ml/kg. Spin-echo sequences were performed before and immediately after injection. The safety and efficacy of the two contrast media were assessed. No changes were observed in blood pressure, heart rate or neurological status. Five adverse effects (two episodes of headaches, two of nausea and one of dizziness) were reported by 2 patients who received gadodiamide injection and 1 who received gadopentetate dimeglumine. All events were mild and their relationship to the contrast media was uncertain. For both contrast media statistically significant changes in serum iron were observed 24 h after injection. More than 70% of the patients had abnormal findings on MRI, and in 56% of these contrast enhancement of the abnormal structure or lesion was seen. Contrast enhancement provided the diagnosis in about 50%, changed it in 40% and increased diagnostic confidence in 95%.     

Gadopentetate-dimeglumine-enhanced MR imaging of osteonecrosis and osteochondritis dissecans of the elbow: initial experience

Magnetic resonance imaging (MRI) was performed on seven patients with aseptic osteonecrosis (n=4) and osteochondritis dissecans (OCD;n=3) of the elbow. Precontrast MRI was superior to plain radiographs, which did not show any abnormality in three cases of osteonecrosis. On gadopentetate-dimeglumine-enhanced T1-weighted images, which were obtained in three patients with osteonecrosis and three patients with OCD, all cases of osteonecrosis demonstrated homogeneous enhancement of the lesions. All cases of OCD were diagnosed on plain radiographs. On MRI one showed significant enhancement of the loose body. In another case an incompletely enhancing loose body was surrounded by a diffusely enhancing region. In the third patient only a small marginal enhancement of the defect was observed. Our results suggest that MRI can improve the accuracy in diagnosis of aseptic osteonecrosis of the elbow. The use of gadopentetate dimeglumine allows the viability of the lesions or the loose bodies to be demonstrated and reparative tissue to be detected.     

MR imaging of orbital mass lesions with contrast agent: A preliminary report

To investigate the advantage and limit of contrast enhancement in the examination of orbital mass lesions, precontrast T1- and T2-weighted, and postcontrast T1-weighted spin-echo images were retrospectively compared by two experienced observers. Using contrast material, intraocular tumors were well detected and characterized, and several orbital tumors were characterized as to whether cystic or necrotic and intracranial involvement was better evaluated. On the other hand, tumor-fat interface lost conspicuity when tumors showed enhancement. We conclude that gadopentetate-dimeglumine-administered T1-weighted images were helpful in detecting, differentiating and characterizing tumors of the orbit. However, the loss of contrast with fatty tissue is a disadvantage to be considered.     

3.0T MR动态增强扫描半定量分析对腮腺肿块鉴别诊断的价值

目的 探讨3.0 TMR动态增强扫描(DCE-MRI)半定量分析对腮腺肿块鉴别诊断的价值.方法 分析43例患者经手术病理证实的63个腮腺肿块的所有MRI平扫及DCE-MRI资料,分析每个肿块内感兴趣区(ROI)的时间-信号曲线(TIC)特点,对所得数据进行统计学分析.结果 63个肿块中,8个恶性肿瘤及3个感染性病变曲线类型均为C型(平稳型,上升后处于平稳状态);7个混合瘤、1个基底细胞腺瘤、2个神经源性肿瘤、1个囊肿曲线类型均为A型(持续上升型);40个腺淋巴瘤中有32例曲线类型为B型(廓清型,上升后快速廓清),8例为C型;1例嗜酸细胞腺瘤亦为B型.良性肿瘤与恶性肿瘤、良性肿瘤与感染性病变的曲线类型差异有统计学意义(P＜0.001);恶性病变与感染性病变曲线类型差异没有统计学意义.恶性肿瘤与腺淋巴瘤、恶性肿瘤与混合瘤、腺淋巴瘤与混合瘤的廓清率(WR)差异均有统计学意义(P＜0.001).结论 DCE-MRI半定量分析有助于腮腺肿块的鉴别诊断.     

乳腺癌MRI强化特征与免疫组织化学相关性分析

目的 探讨乳腺癌MRI强化特征与乳腺免疫组织化学之间的内在联系.方法 搜集经病理及免疫组织化学证实的85例乳腺癌患者,均行乳腺动态增强MRI检查,按照乳腺影像报告和数据系统(BI-RADS)描述病灶MRI强化特征,分析其与ER、PR、Her-2、Ki-67表达的相关性.结果 乳腺癌病灶MRI强化类型、强化形态、强化边缘与ER、PR、Ki-67的表达具有统计学意义,与Her-2的表达无统计学意义;病灶内部强化特征与Ki-67的表达具有统计学意义,与ER、PR、Her-2的表达无统计学意义;病灶时间-信号强度曲线与ER、Ki-67的表达具有统计学意义,与PR、Her-2的表达无统计学意义.结论 乳腺癌的MRI强化特征与免疫组织化学标记物的表达存在一定的关联,从影像角度评估乳腺癌的生物学行为和预后有一定的参考价值.     

Stability of osteochondral fragments of the femoral condyle: magnetic resonance imaging with histopathologic correlation in an animal model

The stability of surgically induced osteochondral fragments of the femoral condyle was examined by magnetic resonance imaging (MRI) using T1- and T2-weighted spin echo sequences in 7 dogs; contrast-enhanced T1-weighted spin-echo sequences were also obtained. Animals were sacrificed between the 34th and 196th day after surgery. MR images were compared with the histopathologic findings. Two loose and five stable fragments were found after injection of contrast medium. With the loose fragments, a well-defined line of high signal intensity between the fragment and the epiphysis showed marked enhancement. Histological examination revealed vascularized granulation tissue at the interface. Stable fragments also showed a similar, but irregularly defined line on plain sequences, but no enhancement after injection of contrast medium; histological examination showed no granulation tissue at the interface but intact bone trabeculae within the completely repaired fracture. Fibrocartilaginous repair at the articular cartilage surface also showed enhancement. Contrast-enhanced MR imaging allowed an exact delineation of the line of separation of unstable osteochondral fragments in this animal model with differentiation from a similar line occurring in stable fragments. However, this interface line in relation to stable fragments could not be explained histologically and probably reflects differences of binding or distribution of protons in healing osteochondral fragments.     

多层螺旋CT与钆贝葡胺增强MRI对肝癌诊断价值比较

目的 比较多层螺旋CT与钆贝葡胺（Gd-BOPTA）增强MRI对肝癌的诊断价值。资料与方法 对19例同组患者依次行多层螺旋CT双期增强扫描、MR平扫及Gd-BOPTA动态、延迟扫描。比较多层螺旋CT动态增强扫描、MR平扫＋Gd-BOPTA动态扫描及联合MRI3种方法病灶检出的敏感性及对肝癌病灶定性诊断的敏感性、特异性和准确性。结果 3组病灶检出的敏感性及对肝癌病灶诊断的准确性以联合MRI组较高,差异有统计学意义。结论 Gd-BOPTA增强MRI对病灶检出的敏感性及肝癌病灶诊断的准确性优于多层螺旋CT。     

Gadobenate dimeglumine-enhanced liver MR imaging: value of dynamic and delayed imaging for the characterization and detection of focal liver lesions

The aim of this study was to determine the value of delayed-phase imaging (DPI) of gadobenate dimeglumine (Gd-BOPTA)-enhanced MR imaging for the evaluation of focal hepatic tumors compared with precontrast imaging and early dynamic phase imaging. The MR images were obtained in 48 patients with 98 focal hepatic tumors. Three-dimensional gradient-echo (GRE) imaging obtained before and 30, 60, and 1 h after administration of 0.1 mmol/kg of gadobenate dimeglumine. Each image set was analyzed qualitatively (lesion detection, conspicuity, delineation, and enhancement pattern on DPI) and quantitatively [signal-to-noise ratio (SNR), tumor–liver contrast-to-noise ratio (CNR)]. Improved lesion-to-liver contrast during the dynamic phase imaging was observed compared with precontrast images. The DPI showed a homogeneous enhancement of liver parenchyma and distinctive enhancement features of focal liver lesions: metastases (85%) showed a target shaped enhancement, and hepatocellular carcinomas (HCCs) showed an inhomogeneous (58%) or homogeneous enhancement (21%). The DPI showed better performance for the detection of metastases than other images by increasing lesion delineation (p<0.05). The absolute CNR of metastasis measured from periphery of the tumors on DPI was greater than precontrast and arterial phase imaging (p<0.05). The Gd-BOPTA during both dynamic and delayed phases provides valuable information for the characterization of focal liver lesions, and furthermore, Gd-BOPTA-enhanced DPI contributed to the improved detection of liver metastasis compared to precontrast and early dynamic imaging.