MRCP 3D FRFSE系列对良恶性胰胆管梗阻的诊断价值

目的探讨三维快速恢复快速回波脉冲系列磁共振胰胆管水成像(MRCP 3D FRFSE)对良恶性胰胆管梗阻的临床应用价值。方法对106例临床疑有胰胆管梗阻患者行MRCP 3D FRFSE系列检查,2位高年资放射科医师前瞻性分析图像,结果与手术病理或临床随访结果比较。结果106例MRCP检查均一次性成功,肝内外胆管显示率为100%,主胰管显示率为93.4%,其中80例良性梗阻包括肝内外胆管结石66例,乳头炎6例,十二指肠降段憩室炎2例,十二指肠腺瘤样增生1例,慢性胰腺炎5例;26例恶性梗阻包括肝外胆管癌9例,壶腹癌5例,胆囊癌4例,胰头癌8例。MRCP对胰胆管梗阻的定位诊断准确率为100%,在区分良恶性梗阻中,敏感性92.3%,特异性96.3%,准确性95.3%。结论3D FRFSE系列的MRCP是区分良恶性胰胆道梗阻病变较为理想的技术,在临床上有较大的应用价值。     

MR cholangiopancreatography: technique, potential indications, and diagnostic features of benign, postoperative, and malignant conditions

The objective of this article is to review technical aspects, discuss potential clinical indications for MR cholangiopancreatography (MRCP) and demonstrate the spectrum of diagnostic findings in benign, postoperative, and malignant conditions. We describe our current imaging protocol in comparison with other available techniques. Using a non-breath-hold, heavily T2-weighted fast-spin-echo (FSE) sequence with or without respiratory gating we obtained coronal and axial source images and maximum intensity projections (MIPs) in 102 patients with suspected abnormalities of the biliary or pancreatic ducts. Based on this series we demonstrate the diagnostic appearance of a variety of benign, postoperative, and malignant conditions of the biliary and pancreatic ducts and discuss potential clinical indications for MRCP. The non-breath-hold FSE technique enables a consistent image quality even in patients who cannot cooperate well. Respiratory gating increased the rate of diagnostic examinations from 79 to 95 %. Acquisition of coronal and axial source images enables detection of bile duct stones as small as 2 mm, although calculi that are impacted and not surrounded by hyperintense bile may sometimes be difficult to detect. The MIP reconstructions help to determine the level of obstruction in malignant jaundice, delineate anatomical variants and malformations, and to diagnose inflammatory conditions, e. g., sclerosing cholangitis, the Mirizzi syndrome and inflammatory changes in the main pancreatic duct. The MRCP technique also correctly demonstrates the morphology of bilio-enteric or bilio-biliary anastomoses. Because MRCP provides sufficient diagnostic information in a wide range of benign and malignant biliary and pancreatic disorders, it could obviate diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in many clinical settings. The ERCP technique may be increasingly reserved for patients in whom nonsurgical interventional procedures are anticipated. Received 25 July 1996; Revision received 1 October 1996; Accepted 5 November 1996     

单次激发磁共振胰胆管造影的临床应用

目的：探讨单次激发快速自旋回波（ＳＳＦＳＥ）序列磁共振胰胆管造影的临床应用价值。方法：采用屏气、重Ｔ２ 加权、单次激发快速自旋回波（ＳＳＦＳＥ）序列、二维多平面成像技术做ＭＲ胰胆管造影８０ 例,其中３０ 例为正常者,５０例疑为胰胆系疾病的病人。结果：３０例正常者的胰胆管和胆囊的显示率为１００％ 。５０例疑为胰胆系疾病的病人,ＭＲＣＰ良好显示胰胆系病变部位及扩张的胰胆管,结合腹部常规ＭＲ,获得理想的综合影像诊断。结论：ＳＳＦＳＥ序列ＭＲＣＰ是一种安全简便、无创伤性的胰胆管影像学检查新技术,快速成像,图像清晰,具有重要的临床应用价值。     

静脉注射联合口服钆喷酸葡胺磁共振胆胰管成像在低场强MR的应用

目的分析口服稀释静脉用钆喷酸葡胺溶液作为低场强磁共振胃肠道阴性对比剂及联合静脉注射钆喷酸葡胺磁共振胆胰管成像(MRCP)在低场MR中用于显示胆胰管及疾病的能力。方法 30例临床可疑有胆胰管病变的患者,均有不同程度胆系梗阻、腹痛、不同程度皮肤或巩膜黄染等,部分有腹部肿块,均行MR平扫、Gd-DTPA(钆喷酸葡胺)强化检查,部分同时行超声及CT检查。结果 30例受检者均能清楚显示胆胰管树,并能清晰显示病变位置,其中18例发现肝内胆管占位,10例发现肝内胆管、肝外胆管及(或)胆囊结石,2例胰头占位。结论口服钆喷酸葡胺溶液可抑制胃及十二指肠内潴留液的高信号以及胆胰管树背景的小血管信号,改善MRCP图像的质量,结合肝胆MR平扫、强化应用具有较高的肝内、外胆管显示率及肝内、外胆管病变的显示能力,能为胆胰管病变的诊断及鉴别诊断提供更多帮助。     

低场强磁共振胰胆管成像技术的临床应用

目的：探讨低场强ＭＲ胰胆管成像技术及临床应用价值。材料与方法：以０．３低场强ＭＲ、重Ｔ２ＷＩ ＭＲ水成像技术做胰胆管造影４０例。采用快速自旋回波（ＦＳＥ）非屏气扫描技术,加大ＴＲ／ＴＥ技术参数。图像经计算机叠加重建处理。结果：４０全名有１１例胰胆管正常;２９例患有胰胆疾患,其中１４例经手术病理证实。阳性患者均能显示各类疾病的异常改变,阴性者能展示胆总管、胆囊、肝总管、左右肝管的形态。结论：低场强Ｍ     

改良快速自旋回波在MR胰胆管成像中的应用

目的：探讨改良快速自旋回波在胰胆管ＭＲＩ成像中的临床应用价值。材料与方法：３例胆囊摘除术后，４例胆结石，１例肝硬化并肝功能不全患者以及２名健康志愿者。应用改良快速自旋回波和脂肪抑制序列行ＭＲＩ检查，被检者屏气１８ｓ进行信号采集，经过重建而获得胰胆管成像。结果：胆囊（除３例已摘除外）７例中显示６例，１例胆囊内充满结石而不显示，胆总管，肝总管及左右肝管分别显示９例，主胰腺管显示３例。胆囊结石３例被检出，表现为胆囊内大小不等之圆形低信号区。结论：应用改良快速自旋回波技术，减少信号采集时间，缩短了ＭＲ胰胆管成像中患者的屏气时间，同样能清晰地显示胰胆管系统并对胰胆道疾病作出诊断     

Malignant obstructive jaundice: comparison of MRCP and ERCP in the evaluation of distal lesions

PURPOSE: To compare the diagnostic accuracy of MR cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of malignant stenosis of the distal common bile duct. MATERIALS AND METHODS: Twenty-one patients (12 males and 9 females, mean age 62 years) with a clinical suspicion of malignancy of the distal biliary tract and pancreatic head underwent tomographic RM evaluation and diagnostic MRCP, followed by diagnostic and, where possible, therapeutic ERCP. The images obtained with ERCP and MRCP were reviewed blind by two experts who evaluated the presence, site, signal features and locoregional extension of the tumours. Histology performed by brushing or biopsy during ERCP and after surgical resection provided the standard of reference for all 21 patients. RESULTS: CPRM correctly identified the presence and site of the distal biliary stenosis in 21/21 (100%) cases, as well as allowing evaluation of the upper abdomen by associating it with conventional MRI. ERCP, instead, allowed detection of the presence and site of biliary stenosis in 20/21 (95%) cases. DISCUSSION AND CONCLUSIONS: ERCP may have some limitations as regards identification of distal bile duct stenosis in cases of critical stenosis. The non-invasive nature and panoramic capabilities of MRCP and the fact that no contrast material is needed make MRCP the examination of reference in the diagnosis of malignant stenosis of the distal bile duct, also thanks to its ability to visualise the entire biliary tree in the presence of critical strictures of the common bile duct. The rationale for the use of ERCP lies in the possibility of taking histological samples and performing minimally invasive surgical interventions.     

Clinical efficacy of 3D-MR cholangiopancreatography (MRCP) with the T2Plus technique

The T2Plus technique is an MR method in which longitudinal magnetization is recovered by the application of a -90 degrees radiofrequency pulse in the recovery period after data acquisition. The present study was performed to evaluate the efficacy of the 3D-fast advanced spin echo (FASE) sequence with T2Plus technique in improving the image quality of respiratory-triggered 3D-MRCP. We performed a phantom study and clinical study in 60 cases. In the clinical study, ERCP and CT images were used as the gold standard for evaluating visualization of the pancreato-biliary system with the T2Plus technique. In the phantom study, the signal-to-noise ratio (SNR) of distilled water was higher in the shorter TR owing to the effectiveness of the T2Plus technique. The contrast-to-noise ratio (CNR) of the biliary tract and the pancreatic duct to the liver were significantly higher (P<0.05) with the T2Plus technique. On visual evaluation by two experienced abdominal radiologists, the left and right hepatic duct, common hepatic duct, common bile duct, main pancreatic duct, and accessory pancreatic duct were visualized more clearly with the T2Plus technique (P<0.05). Improvement of the image quality of MRCP can be obtained by applying the T2Plus technique.     

磁共振胰胆管成像诊断胰胆管合流异常的价值

目的 探讨磁共振胰胆管成像（MRCP）诊断胰胆管合流异常（APBDU）的价值。资料与方法 分析11例患者的MRCP、轴面T2WI及T1WI。测量共通管长度和胆总管宽度,观察APBDU的形式,以及胆管内有无结石和肿瘤等相关疾病。将观察结果与B超及内镜逆行性胰胆管造影（ERCP）检查和／或外科手术所见对照。结果 10例胆总管囊肿型APBDU包括胆管囊状扩张7例,梭形扩张3例;1例非囊肿型APBDU表现为胆总管轻度扩张。胆总管最大直径范围是12～90mm,平均34mm。APBDU的合流形式包括A型7例,B型4例,在MRCP图像测量的共通管长度范围是18～30mm,平均23mm。轴面T2WI显示胆总管或胰管突然蝌蚪或逗点样增粗5例。APBDU相关疾病包括胆囊／胆管结石6例,胆管肿瘤1例,胰腺炎5例。对7例切除的病变胆管和胆囊标本进行病理组织学检查,均有慢性炎症改变。结论 MRCP检查有助于发现和诊断APBDU,轴面T2WI和B超检查阴性结果不能完全排除本病。     

单次激发磁共振胰胆管成像与常规磁共振胰胆管造影的比较

比较单次激发磁共振胰胆管成像(SSMRCP)和常规磁共振胰胆管造影(CMRCP),评价SSMRCP的临床应用 价值。材料与方法81例梗阻性黄疸、1例胆管-空肠吻合术后及61例无黄疸患者行OMRC、SSMRC单层及多层扫描, 比较两种技术诊断的准确性。结果三个序列均能显示胆管病变部位、疾病特征、近侧扩张胆管以及远侧正常胰胆管;显 示扩张胆管直径三个序列间没有显著性差异;SSMRCP多层显示胆管病变细节较好,而SSMRCP单层显示胰管则明显优 于另两种方法。结论SSSMRCP可代替OMRCP,准确地、更快速地诊断胆管系统疾病,并能更好地显示正常胰管。     

MR cholangiopancreatography versus endoscopic sonography in suspected common bile duct lithiasis: a prospective, comparative study

OBJECTIVE: Our purpose was to compare the accuracy of MR cholangiopancreatography and endoscopic sonography for the diagnosis of common bile duct stones in patients with a mild to moderate clinical suspicion of common bile duct stones. SUBJECTS AND METHODS: Forty-seven patients were prospectively enrolled. Inclusion criteria included acute pancreatitis, subclinical jaundice, and clinical features of common bile duct stone migration. Radial endoscopic sonography and MR cholangiopancreatography with the single-shot fast spin-echo technique were performed a maximum of 48 hr apart. The gold-standard diagnosis was obtained with ERCP (n = 20) or intraoperative cholangiography (n = 14) if the results of endoscopic sonography or MR cholangiopancreatography were abnormal or if a cholecystectomy was performed, or by clinical and biochemical follow-up (n = 11) if the results of endoscopic sonography and MR cholangiopancreatography were normal. RESULTS: The final diagnosis was common bile duct stones in 16 patients, malignant obstructions in four, and another biliary disease in two (lithiasis migration aspect with papillary edema); 23 patients had no biliary disease. The sensitivity and specificity of MR cholangiopancreatography were, respectively, 90.5% and 87.5% for etiologic diagnosis and 87.5% and 96.6% for the detection of common bile duct stones. The corresponding values for endoscopic sonography were 86.4% and 91.3% for etiologic diagnosis and 93.8% and 96.6% for visualization of choledocholithiasis. Accuracy did not significantly differ between the techniques. CONCLUSION: In cases of mild to moderate suspicion of choledocholithiasis, the accuracies of endoscopic sonography and MR cholangiopancreatography are similar. Because MR cholangiopancreatography is noninvasive, it may be preferred for this indication.     

Differential diagnosis of periampullary carcinomas at MR imaging.

Periampullary carcinomas arise within 2 cm of the major duodenal papilla and comprise carcinomas of the ampulla, distal common bile duct, pancreas, and duodenum. Their clinical features and anatomic locations are similar, as are the therapeutic approaches; however, their long-term outcomes vary. Magnetic resonance (MR) images of 89 pathologically proved periampullary carcinomas (29 ampullary carcinomas, 27 distal common bile duct carcinomas, 21 pancreatic carcinomas, six duodenal carcinomas, and six unclassified carcinomas) were reviewed. Ampullary carcinoma manifests as a small mass, periductal thickening, or bulging of the duodenal papilla. Pancreatic carcinoma is characterized by a discrete parenchymal mass, which enhances poorly on dynamic gadolinium-enhanced images. Sometimes, two proximal and two distal pancreatic and biliary ducts appear as four separate ducts (the four-segment sign). Dilatation of side branches of the pancreatic ducts is frequently seen in pancreatic carcinoma but not in other periampullary carcinomas. Distal bile duct carcinoma manifests as luminal obliteration and wall thickening or as an intraductal polypoid mass. A dilated proximal bile duct, a nondilated distal bile duct, and a dilated or nondilated pancreatic duct may form the three-segment sign. MR cholangiopancreatography and sectional MR imaging are useful in determining the origins of periampullary carcinomas.     

Ampullary carcinoma: Demonstration by current MR techniques

The objective of this study was to demonstrate the appearance of ampullary carcinoma using current MR techniques, including fat suppression, gadolinium enhancement, and MR cholangiography. Nine patients with ampullary carcinoma were examined by MRI at 1.5 T. MR examinations included T1-weighted spoiled gradient echo, T1-weighted fat-suppressed, and immediate postgadolinium spoiled gradient echo images for all patients and MR cholangiography for three patients. The imaging features of ampullary carcinomas, including tumor size and morphology, signal intensity, and enhancement characteristics, were determined. Ampullary carcinomas shown on MR images ranged in size from 1.5 to 5.5 cm. Tumors were low in signal intensity on precontrast T1-weighted spoiled gradient echo and T1-weighted fat-suppressed images relative to normal pancreatic tissue and enhanced less than normal pancreas on immediate postgadolinium spoiled gradient echo images. Tumor conspicuity was greatest on immediate postgadolinium spoiled gradient echo images. MR cholangiography demonstrated high grade obstruction of the common bile duct and mild dilatation of the pancreatic duct at the level of the ampulla with abrupt termination of the ducts in two untreated patients and moderate dilatation of the common bile duct in one patient who had a biliary stent. Ampullary carcinomas can be demonstrated on MR images as small masses arising at the ampulla. Tumors are well defined on immediate postgadolinium spoiled gradient echo images.     

MRI of the biliary and pancreatic ducts

Magnetic resonance Cholangiopancreatography (MRCP) is a non-invasive imaging technique able to provide projectional images of the bile ducts. Different sequences, using both breath-hold and non-breath-hold acquisition techniques, have been employed in order to obtain MRCP images. The authors discuss technical aspects, considering both three-dimensional non-breath-hold techniques and two-dimensional breath-hold, multi-slice and thick slab sequences. Clinical applications of MRCP are evaluated, presenting data from both the literature and personal experience. The main indication for MRCP study is represented by the evaluation of common bile duct obstruction, with the aim of assessing the presence of the obstruction (accuracy 85–100 %) and, subsequently, its level (accuracy 91–100 %) and its cause. The utility of associating conventional MR images to MRCP in malignant strictures, in order to characterize and stage the malignant lesion, is also discussed. Finally, data are presented regarding the indications and the utility of MR-pancreatography in the evaluation of patients with pancreatic duct anomalies and chronic pancreatitis.     

螺旋CT在先天性胆管扩张症中的诊断价值

目的探讨螺旋CT在先天性胆管扩张症的诊断价值。方法回顾性分析6例先天性胆管扩张症息者的CT资料，并和US、ERCP和手术结果进行对比分析。结果所有病例的轴位、MPR和三维图像很好的显示肝内外胆管的解剖形态，清楚地显示扩张的肝内外胆管。其中Ⅰ型单纯性胆总管扩张3倒。Ⅳ肝内外胆管均扩张2例，Ⅴ型肝内胆管扩张（Caroli’s病）1例。结论螺旋CT可以很好的显示扩张的肝内外胆管的形态、部位以及周围组织结构。能为临床提供有价值的诊断信息，为手术提供可靠的依据。     

Hepatobiliary and pancreatic manifestations of cystic fibrosis: MR imaging appearances.

Magnetic resonance (MR) imaging and MR cholangiopancreatography are useful, noninvasive techniques for the assessment of pancreatic and hepatobiliary complications in cystic fibrosis. Abnormalities of the pancreas in cystic fibrosis are typically characterized by fat deposition, which has increased signal intensity on T1-weighted MR images, and pancreatic fibrosis, which has low signal intensity on both T1- and T2-weighted images. Pancreatic cysts are a relatively common finding; these cysts are typically quite small but are well demonstrated at MR imaging and MR cholangiopancreatography. Pancreatic duct abnormalities are also occasionally seen. Hepatic manifestations range from hepatomegaly and diffuse fatty infiltration to severe cirrhosis with fibrotic change, regenerative nodules, and portal hypertension. Splenomegaly is often characterized by siderotic nodules that manifest as multiple focal areas of abnormal low signal intensity within the spleen. Biliary manifestations include cholelithiasis, stricturization, and narrowing or dilatation of intra- and extrahepatic bile ducts. Gallbladder abnormalities including microgallbladder are also readily demonstrated. MR cholangiopancreatography can be used to help determine the presence and severity of biliary complications without resorting to more invasive procedures and, in conjunction with MR imaging, may prove useful in the assessment of patients with cystic fibrosis who present with abdominal symptoms that suggest hepatobiliary involvement.     

Magnetic resonance cholangiopancreatography of biliary system abnormalities in children

OBJECTIVE: The aim of this study was to assess the usefulness of magnetic resonance cholangiopancreatography (MRCP) with a single-shot fast spin-echo sequence as a noninvasive method to evaluate the biliary system in children. METHODS: Twenty-five MRCP examinations of 23 patients were evaluated. On the basis of surgical (n=5), endoscopic retrograde cholangiopancreatography (n=4), liver biopsy (n=4), clinical data, and follow-up observation, 6 children were considered to have no significant abnormality. The other 17 children were found to have pancreaticobiliary disease, including choledochal cyst, biliary system dilatation, choledocholithiasis, biliary atresia, multiseptated gallbladder, anomalous pancreaticobiliary union, ruptured hydatic cyst, and biloma. The findings were correlated with the ultrasonography, computed tomography, surgical, and endoscopic retrograde cholangiopancreatography results. RESULTS: Magnetic resonance cholangiopancreatography showed the first branch of the intrahepatic duct, the common hepatic duct, the gallbladder, and the common bile duct in 14 children. Cystic duct was not seen in infants, but was partially visible in younger children. Although the main pancreatic duct was visible in head and body portions in 65% of the patients, it was visible in 17% of the patients in the tail. The diagnostic accuracy of MRCP was 100% in patients with choledochal cysts and stenoses. In a patient with hydatic cyst, cystobiliary communication was successfully demonstrated. CONCLUSION: Magnetic resonance cholangiopancreatography can be used effectively for the evaluation of the biliary system in children.     

胆管磁共振仿真内窥镜的临床应用研究

通过胆管磁共振仿真内窥镜（ＭＲＶＥ）加磁共振胰胆管造影（ＭＲＣＰ）的临床应用,探讨其在胆道方面的诊断价值。方法 １４个月４４例有梗阴性黄疸和有胆道症状的患者行胆管ＭＲＶＥ检查。用呼吸门控快速自旋回波（ＦＳＥ）和屏气多层单次激发快速自旋回波（ＳＳＦＳＥ）序列获得的二维重度Ｔ２ＷＩ传输到计算机工作站,用导航软件显示利用表面应答技术的胰胆管内表面的状态。结果 恶性肿瘤１８例,胆结石１７例、术后胆道并发症     

薄层冠扫SSFSE序列在婴幼儿MR胆道成像中的应用

目的：分析探讨薄层冠扫SSFSE序列在婴幼儿MR胆道成像中的临床应用价值。方法：婴幼儿胆道系统疾病患者24例,包括胆道闭锁7例、胆道扩张症13例、胆系结石4例,均行全腹部薄层冠状面单次激发快速自旋回波（SS-FSE）序列扫描,8例经15～20min延迟后行MRI增强扫描。观察患儿肝内外胆道及其各级分支的解剖全貌、走行分布及通畅情况。结果：所有患儿的MR图像在显示肝胆管解剖方面均可达到质量良好（可显示肝内胆管二级以上分支）。胆道闭锁患儿表现为胆囊形态小或不显影,正常肝外胆道结构消失或显示不完整;胆道扩张症患儿表现为位于胆道走行区的囊性包块,伴或不伴有肝内外胆道不同程度扩张;胆系结石患儿表现为胆道／胆囊内短T2信号充盈缺损,或伴近端胆道扩张。结论：薄层冠扫SSFSE序列具有扫描速度快、呼吸伪影少、无电离辐射、胆道系统与周围背景结构的对比度高等优势,较常规腹部MRI扫描能更细致地观察胆道系统的解剖结构和各级分支的走行、管径,了解病变全貌以及是否合并其它脏器异常,可作为婴幼儿胆道疾病的常规影像学检查手段。     

Evaluation of the pancreas: a comparison of single thick-slice MR cholangiopancreatography with multiple thin-slice volume reconstruction MR cholangiopancreatography

OBJECTIVE: The purpose of this study was to assess abilities of single thick-slice MR cholangiopancreatography and multiple thin-slice multiprojection volume reconstruction (MPVR) MR cholangiopancreatography to evaluate diseases in and around the pancreas. SUBJECTS AND METHODS: Eighty-nine patients underwent both single and MPVR MR cholangiopancreatography using a single-shot fast spin-echo technique. Image quality (five-point scale), visualization of the common bile and pancreatic ducts (three-point scale), stenotic, dilatational, or cystic changes of the pancreatic ducts, and other pathologic findings were evaluated. RESULTS: Image quality was high for single and MPVR MR cholangiopancreatography (4.1+/-0.7 and 4.5+/-0.6, respectively). Misregistration was noted in 19 patients with MPVR MR cholangiopancreatography. Ducts on and around the greater duodenal papilla and the common bile duct were revealed better using MPVR than single MR cholangiopancreatography (p < .05). Overall sensitivity, specificity, and accuracy for detection of stenosis of the main pancreatic ducts were 83.3%, 93.6%, and 88.8%, respectively, using single MR cholangiopancreatography and 76.2%, 97.9%, 87.6%, respectively, using MPVR MR cholangiopancreatography. Dilatation of the pancreatic ducts (100%) and cystic changes (n = 17 and n = 19, respectively) were well seen using either single or MPVR MR cholangiopancreatography. Although stenotic changes of the nondilated main pancreatic ducts and their branches were difficult to evaluate using single (62.5% and 14.3%, respectively) or MPVR (43.8% and 21.4%, respectively) MR cholangiopancreatography, single MR cholangiopancreatography better depicted ductal continuity. CONCLUSION: For evaluation of the pancreas, single and MPVR MR cholangiopancreatography provide complementary data; thus, we recommend using a combination of these two MR cholangiopancreatography techniques.