Comparison of MR cholangiopancreatographic techniques with contrast-enhanced cholangiography in the evaluation of sclerosing cholangitis.

OBJECTIVE: The purpose of our study was to compare MR cholangiopancreatography and contrast-enhanced cholangiography in patients with sclerosing cholangitis. MATERIALS AND METHODS: Twenty patients with sclerosing cholangitis were evaluated on MR cholangiopancreatography using the single-shot fast spin-echo technique at 1.5 T. A group of 19 healthy volunteers underwent MR cholangiopancreatography as controls. Thick-slab (2-cm sections) coronal oblique and thin-slab (5-mm sections) interleaved straight coronal MR images were obtained. All patients with sclerosing cholangitis had an MR cholangiopancreatogram within 12 months of a contrast-enhanced cholangiogram (mean, 3.8 months). Seventy-five percent of patients had an MR cholangiopancreatogram within 3 months of the contrast-enhanced cholangiogram. The MR cholangiopancreatograms and contrast-enhanced cholangiograms were reviewed independently in a random fashion by two radiologists who were unaware of clinical history for the degree of ductal visualization and for the presence and location of strictures of the intrahepatic and extrahepatic bile ducts. All discrepancies were resolved by a consensus, and the contrast-enhanced cholangiograms were regarded as the gold standard. Statistically significant data were calculated using the signed rank test (p < 0.01), and agreement analysis was calculated using Cohen's kappa. RESULTS: All findings on MR cholangiopancreatograms in healthy subjects were interpreted as normal, and all findings on MR cholangiopancreatograms in patients with sclerosing cholangitis were interpreted as abnormal. When compared with the control group, scans of patients with sclerosing cholangitis usually showed good visualization (>50%) of the intrasegmental (86% vs 9%) and peripheral (67% vs 0%) intrahepatic ducts on thick-slab MR cholangiopancreatography. Thick-slab MR cholangiopancreatography showed good visualization in more ducts than contrast cholangiography (84% vs 70%; p = 0.10) and showed more strictured ducts than contrast cholangiography (47% vs 36%; p = 0.22). When comparing those ducts with good visualization on both MR cholangiopancreatography and contrast cholangiography, we found that disagreement occurred regarding 32% of ducts. Most of the discrepancies (60%) resulted when a stricture was noted on MR cholangiopancreatography but not on contrast-enhanced cholangiography. Good interobserver agreement (kappa > 0.4) was noted for detecting strictures of the extrahepatic, left hepatic, left medial, and right posterior ducts, with the greatest agreement for extrahepatic ductal strictures (kappa = 0.8). CONCLUSION: Thick-slab MR cholangiopancreatography is the best technique for depicting normal and strictured bile ducts and allows the differentiation of healthy patients from patients with sclerosing cholangitis. Although endoscopic retrograde cholangiopancreatography was considered the standard, MR cholangiopancreatography was superior for intrahepatic biliary ductal visualization. Therefore, this technique is of value in the diagnosis and follow-up of patients with sclerosing cholangitis.     

Percutaneous cholecystography in children

Percutaneous cholecystography was performed on 13 children who had biliary system abnormalities: two had biliary hypoplasia, five had sclerosing cholangitis, three had cirrhosis, two had distal choledochal obstruction, and one had an obstructed portoenterostomy. In 12 patients transcholecystic cholangiography showed, without significant complications, the intra-and extrahepatic bile ducts. In one patient with primary sclerosing cholangitis, the intrahepatic bile ducts were not opacified satisfactorily; dilatation of the gallbladder required surgical drainage. The transcholecystic technique is indicated when the intrahepatic bile ducts are either mildly dilated or not dilated.     

Role of MR cholangiopancreatography in patients with failed or inadequate ERCP

OBJECTIVE: The purpose of this study was to evaluate the spectrum of MR imaging features of primary sclerosing cholangitis. MATERIALS AND METHODS: A retrospective review was performed of MR imaging findings including MR cholangiography and multiphasic contrast-enhanced dynamic sequences in 22 patients with primary sclerosing cholangitis. MR imaging analysis included abnormalities of intra- and extrahepatic bile ducts, abnormalities of liver parenchyma, changes in liver morphology, and lymphadenopathy. RESULTS: Abnormal findings of bile ducts were seen in all 22 patients; the most common finding was intrahepatic bile duct dilatation (77%), followed by intrahepatic bile duct stenosis (64%), extrahepatic bile duct wall enhancement (67%), extrahepatic bile duct wall thickening (50%), extrahepatic bile duct stenosis (50%), and intrahepatic bile duct beading (36%). Increased enhancement of the liver parenchyma on dynamic arterial-phase images, predominantly in the peripheral areas of the liver, was identified in 56% of patients. Other findings included periportal lymphadenopathy (77%), periportal high signal intensity on T2-weighted images (68%), hypertrophy of the caudate lobe (68%), and abnormal hyperintensity of the liver parenchyma on T1-weighted images (23%). CONCLUSION: On MR imaging, primary sclerosing cholangitis showed several characteristic features, including bile duct abnormalities and increased enhancement of the liver parenchyma. MR cholangiography and contrast-enhanced dynamic MR techniques are useful for revealing intra- and extrahepatic signs of primary sclerosing cholangitis.     

Clinical impact of MR cholangiopancreatography in patients with biliary disease

PURPOSE: To evaluate the role of MR Cholangiopan-creatography (MRCP) as a first imaging modality in patients with suspected biliary tree pathology and indications to endoscopic retrograde cholangiopancreatography (ERCP). MATERIAL AND METHODS: Eighty-eight patients, with clinical signs of biliary tree pathology underwent MRCP, performed with a 1.5 T unit and a phased-array coil. Surgery, intraoperative cholangiography, percutaneous transhepatic cholangiography (PTC) or ERCP were regarded as the gold standard in patients with obstruction; the remaining patients underwent follow-up MRCP examinations at 6-9 months. The MR examination was performed with baseline T1w 2D FLASH and T2w TSE sequences, followed by the MRCP study (single-slab breath-hold RARE and multislice breath-hold HASTE sequences). The MR images were independently evaluated by two radiologists. RESULTS: MRCP showed normal findings in 20 patients; 68 patients had biliary duct dilatation. In 11 out of 68 patients MRCP did not identify any obstruction (9/11 were true negative cases). A diagnosis of benign obstruction was expressed in 36/59 patients (4 chronic pancreatitis, 29 choledocolithiasis, 4 inflammatory obstruction, 2 primary sclerosing cholangitis), with 1 false positive and 5 false negatives (sensitivity, specificity and diagnostic accuracy of 86%, 95% and 90%, respectively). MRCP identified 23 neoplastic stenoses (20/23 were true positives): the sensitivity, specificity and diagnostic accuracy values were 100%, 87% and 95%, respectively. MRCP correctly identified the level of obstruction in 100% of cases. CONCLUSIONS: MRCP may be considered as a first-step imaging method in patients with clinical signs of biliary disease. The workload of ERCP in the diagnostic stage could therefore be reduced and its use be reserved for therapeutic indications.     

MR cholangiopancreatography in patients with primary sclerosing cholangitis: interobserver variability and comparison with endoscopic retrograde cholangiopancreatography

OBJECTIVE: The purpose of our study was to determine the degree of interobserver variability and correlation between MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) for the presence of bile duct strictures in patients with primary sclerosing cholangitis. MATERIALS AND METHODS: For this retrospective study involving 26 patients with primary sclerosing cholangitis, 31 MR cholangiopancreatograms were compared with 30 endoscopic retrograde cholangiopancreatograms. The MR cholangiopancreatograms were independently interpreted by two abdominal radiologists in a blinded, randomized manner for overall image quality, extent of ductal visualization, and the presence and location of bile duct strictures. Unweighted multirater kappa coefficient values were estimated for each comparison. RESULTS: Visualization of more than 50% of the expected ductal length was possible in the extrahepatic, central intrahepatic, and peripheral intrahepatic bile ducts in 99%, 88%, and 69% of the MR cholangiopancreatograms and 100%, 86%, and 52% of the endoscopic retrograde cholangiopancreatograms, respectively. Strictures were detected in the extrahepatic, central, and peripheral ducts in 53%, 68%, and 87% of the MR cholangiopancreatograms and 73%, 67%, and 63% of the endoscopic retrograde cholangiopancreatograms, respectively. The interobserver agreement for stricture detection was 61% for MR cholangiopancreatography and 76% for ERCP. MR cholangiopancreatographic findings were consistent with ERCP findings for the presence of strictures in 69% of the cases. CONCLUSION: In patients with primary sclerosing cholangitis, MR cholangiopancreatography better shows the bile ducts and can depict more strictures, especially of the peripheral intrahepatic ducts, than ERCP. MR cholangiopancreatography can be used to noninvasively diagnose and follow up patients with primary sclerosing cholangitis.     

How reliable is MRCP with an SS-FSE sequence at 3.0 T: comparison between SS-FSE BH and 3D-FSE BH ASSET sequences

PurposeThe purpose of the present study was to evaluate the visibility and the image quality of the biliary and pancreatic duct system on magnetic resonance cholangiopancreatography (MRCP) images based on two breath-hold (BH) methods using array spatial sensitivity technique: a single-shot fast spin-echo (SS-FSE) sequence and a three-dimensional single slab fast spin-echo (3D-FSE) sequence.Materials and methodsIn the present prospective comparative study, 47 patients (22 male and 25 female, mean age=50 years, age range=22–82 years) that were referred for MRCP during a 12-month period are included. All of them were referred with suspected pancreaticobiliary disease. All patients underwent MRCP with both a SS-FSE BH sequence and a 3D-FSE BH sequence. Qualitative evaluation regarding the depiction of three segments of the pancreaticobiliary tree and the frequency of artifacts was performed. Two radiologists graded each sequence of the obtained studies in a blinded fashion. Quantitative evaluation including calculation of relative signal intensity (rSI) and relative contrast (RC) ratios at seven segments of the pancreaticobiliary tree between fluid-filled ductal structures and organ parenchyma at the same ductal segments was performed. In order to evaluate the parameters' differences of the two sequences, either in qualitative or in quantitative analysis, the Wilcoxon paired signed-rank test was performed.ResultsOn quantitative evaluation, both rSI and RC ratios of all segments of the pancreaticobiliary tree at SS-FSE BH sequence were higher than those at 3D-FSE BH sequences. This finding was statistically significant (P< .01). On qualitative evaluation, the two radiologists found intrahepatic ducts and pancreatic ducts to be better visualized with SS-FSE BH than with 3D-FSE BH sequence. This finding was statistically significant (P< .02). One of them found extrahepatic ducts to be significantly better visualized with SS-FSE BH sequence. Moreover, the frequency of artifacts was lower in the SS-FSE sequence, a finding that was of statistical significance. Interobserver agreement analysis found at least substantial agreement (κ>0.60) between the two radiologists.ConclusionThe SS-FSE sequence is performed faster and significantly improves image quality; thus, it should be included into the routine MRCP sequence protocol at 3.0 T. Furthermore, we recommended SS-FSE BH MRCP examination to be applied to uncooperative patients or patients in emergency because of its short acquisition time (1 s).     

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     

Clinical applications of magnetic resonance cholangiopancreatography

Magnetic resonance cholangiopancreatography (MRCP) is the most important diagnostic alternative that has been developed in recent years for the evaluation of the biliary and pancreatic ducts. The advantages of this technique are: it does not use contrast media or ionizing radiation; it is noninvasive and complication free; and, the examination is relatively short (approximately 20 to 30 minutes). MRCP has high sensitivity and specificity for diagnosing biliary dilatation and for determining the site and cause of stenosis. Its diagnostic precision for biliary and pancreatic stones is similar to that of endoscopic retrograde cholangiopancreatography (ERCP). MRCP has replaced ERCP in biliary and pancreatic anatomic variants. In unsuccessful ERCP, MRCP is nearly the only diagnostic modality for the evaluation of the biliary tract. Other applications include primary sclerosing cholangitis, stenosis after liver transplantation, and the evaluation of bilioenteric anastomoses. This article reviews the clinical applications of MRCP in the evaluation of biliopancreatic diseases.     

MR cholangiography in children and young adults with biliary disease

OBJECTIVE: Our objective was to describe the MR cholangiography findings for young patients with suspected biliary disease who underwent half-Fourier acquisition fast spin-echo technique with respiratory triggering. SUBJECTS AND METHODS: Twenty-eight MR cholangiography studies were performed in 22 patients on a 1.5-T MR unit. Ten of these 22 patients had undergone liver transplantation. RESULTS: MR cholangiography revealed abnormalities of both the extrahepatic and the intrahepatic major and minor bile duct systems, despite the small diameter of the duct system in this group of patients. Four patterns of biliary disease were shown: global dilatation of extrahepatic or intrahepatic ducts (n = 7); segmental, uniform dilatation of central or peripheral intrahepatic ducts (n = 9); segmental, nonuniform dilatation of central or peripheral intrahepatic ducts (n = 2); and fusiform ectasia with segmental, irregular intrahepatic dilatation and bile lakes (n = 2). The findings of eight studies were interpreted as normal. The four patterns of abnormalities were correlated with the results from percutaneous transhepatic cholangiography, T-tube cholangiography, and liver biopsy and with clinical and surgical information, as available. CONCLUSION: MR cholangiography is a noninvasive technique for evaluation of biliary disease. The improved resolution afforded by respiratory triggering permits evaluation of both major and minor bile ducts, even in young, uncooperative subjects. Four patterns of abnormalities were prospectively identified, correlated with other information, and used to direct clinical treatment.     

Therapeutic alternatives in the treatment of intrahepatic biliary obstruction

Intrahepatic biliary obstruction was treated in 60 patients (49 with cholangiocarcinoma and 11 with sclerosing cholangitis) who were classified according to the upper limit of their obstruction (Group I, proximal common hepatic duct; Group 2, right and left main hepatic ducts; Group 3, intrahepatic bile ducts). Thirty-six patients underwent percutaneous transhepatic biliary drainage, and 14 underwent catheterization through a T-tube track, Five of this latter group had the T-tube placed to establish a route of access for later interventional radiologic manipulations. Since most diseases that produce intrahepatic biliary obstruction are progressive, the use of any single approach is limited. The advantages of a surgically created route of access combined with the flexibility of interventional radiologic techniques help to maximize the therapy and extend the palliation that many of these patients receive.     

Pancreatic adenocarcinoma: combination of MR imaging, MR angiography and MR cholangiopancreatography for the diagnosis and assessment of resectability

The purpose of this study was to determine the possibility of integrating MR cholangiopancreatography (MRCP) and MR angiography (MRA) to conventional MR images in the diagnosis and assessment of resectability of pancreatic adenocarcinoma. Twenty-three patients with pancreatic adenocarcinoma were prospectively examined with MR. Conventional MR images were acquired in all patients. Three-dimensional MRCP and MRA images were acquired in all patients with suspected biliary and vascular involvement. Acquisition time was less than 45 min in all cases. Images were independently evaluated by two radiologists, with final reading decided by consensus among readers. Diagnosis was confirmed with surgery in 16 patients and with percutaneous biopsy in 7. Concordance among readers was high with a kappa value of 0.83. Pancreatic adenocarcinoma was observed in all patients. Correct assessment of unresectability due to vascular involvement was found in 22 of 23 patients. Biliary obstruction was evident in 13 patients, involving the biliary and pancreatic ducts in 9 and the biliary ducts only in 4. Technical advances permit extensive use of MRI in the evaluation of abdominal pathologies. The combination of MR imaging, MRCP, and MRA can provide sufficient information for the diagnosis and assessment of resectability of pancreatic adenocarcinoma, which otherwise would require three different exams. Received 22 August 1996; Revision received 3 June 1997; Accepted 19 August 1997     

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     

肝吸虫性胆管炎的磁共振胰胆管成像诊断

目的 探讨磁共振胰胆管成像(MRCP)对肝吸虫性胆管炎的诊断价值。方法 使用3D-FASE(三维高级快速自旋回波)重T2加权扫描技术对54例肝吸虫性胆管炎患者进行MRCP检查，并对照内窥镜逆行性胰胆管造影(ERCP)、腹腔镜和手术病理结果。结果 本组54例肝吸虫性胆管炎的MRCP的定性诊断率为88．9％，主要表现为肝内胆管轻度扩张(46例)，末梢胆管囊状扩张(43例)，肝外胆管扩张(15例)和狭窄(19例)，胆总管及胆囊内充盈缺损性低信号(6例)。结论 采用3D FASE重T2WI序列能获得清晰的MRCP图像。肝吸虫性胆管炎的MRCP特征性表现为肝内胆管轻度扩张合并末梢胆管的小囊状扩张，MRCP是诊断肝吸虫性胆管炎较为理想的方法。     

Hepatobiliary and pancreatic MRI and MRCP findings in patients with HIV infection

OBJECTIVE: The purpose of this article is to describe the spectrum of MRI and MR cholangiopancreatography (MRCP) findings of hepatic, pancreatic, and biliary manifestations in patients with HIV infection. CONCLUSION: The spectrum of MRI and MRCP findings in HIV-infected patients includes acute or chronic hepatitis (or both), pancreatitis, cholangitis, acalculous cholecystitis, and biliary strictures that may resemble primary sclerosing cholangitis. The presence of segmental extrahepatic biliary strictures is characteristic of AIDS cholangiopathy.     

CT and MR cholangiography: advantages and pitfalls in perioperative evaluation of biliary tree

Recent developments in imaging technology have enabled CT and MR cholangiopancreatography (MRCP) to provide minimally invasive alternatives to endoscopic retrograde cholangiopancreatography for the pre- and post-operative assessment of biliary disease. This article describes anatomical variants of the biliary tree with surgical significance, followed by comparison of CT and MR cholangiographies. Drip infusion cholangiography with CT (DIC-CT) enables high-resolution three-dimensional anatomical representation of very small bile ducts (e.g. aberrant branches, the caudate branch and the cystic duct), which are potential causes of surgical complications. The disadvantages of DIC-CT include the possibility of adverse reactions to biliary contrast media and insufficient depiction of bile ducts caused by liver dysfunction or obstructive jaundice. Conventional MRCP is a standard, non-invasive method for evaluating the biliary tree. MRCP provides useful information, especially regarding the extrahepatic bile ducts and dilated intrahepatic bile ducts. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRCP may facilitate the evaluation of biliary structure and excretory function. Understanding the characteristics of each type of cholangiography is important to ensure sufficient perioperative evaluation of the biliary system.     

低场强磁共振胆胰管成像(MRCP)的技术应用

目的通过调节低场强(0.3T)MRFSE重T2加权扫描参数,改进扫描角度,评估所获MRCP图像质量及对胆系梗阻疾病定性诊断的准确性.方法50例胆系梗阻患者分两种方法进行检查.全部病例先行常规MRI横轴位T1WI、T2WI扫描;20例为FSET2WI固定参数冠状位扫描;30例改变扫描角度,增强扫描层数,减少层间距,减少信号采集(NSA)次数,缩短扫描时间,其成像效果两组进行比较.结果经调节FSET2WI扫描参数后所获MRCP图像清晰,胆胰管显示边缘清楚,胰管显示率由20%提高到83.3%;定性诊断由88.9%提高到93.3%;梗阻定位诊断为100%.结论低场强MRCP可通过调节扫描参数,提高图像质量和梗阻性黄疸定性诊断准确性,为临床治疗提供可靠依据.     

MR characteristics of acute cholangitis

Purpose: To describe the MR appearance of acute cholangitis and discuss the role of MR imaging as a diagnostic method in this disease.Material and Methods: Of 60 patients with clinical acute cholangitis, 12 were examined with MR before endoscopic retrograde pancreatography (ERCP). A retrospective review was performed of MR and ERCP findings. The MR findings registered were presence of biliary duct dilatation, intraluminal filling defects due to stones or sludge, bands of mucosal oedema of the biliary ducts, intra- and retroperitoneal oedema/fluid, and definition of the cause of obstruction, e.g. stones, stenosis or tumour was made.Results: Acute cholangitis was related to obstruction from choledocholithiasis (n=8), pancreatic cancer (n=1), benign biliary duct stricture (n=1), papillary stenosis (n=1) and without evidence of an obstructing cause (n=1). One patient had an acute obstructive suppurative (toxic) cholangitis.Conclusion: MR imaging has a role in the non-invasive radiographic arsenal of techniques to confirm or exclude the diagnosis of acute cholangitis, especially in older patients where the clinical symptoms may be vague.     

MRI of portal cavernoma with biliary involvement

PURPOSE: To assess the value of MRI in the diagnosis of portal cavernoma with biliary obstruction. MATERIAL: and methods: six patients referred for clinical suspicion of biliary obstruction and portal cavernoma were explored with MRI. all patients were explored using a signa 1.5 t GE MR unit, with high gradient field strength and torso phased array coil. Biliary ducts were explored with ss-fse sequences of MR-cholangiopancreatography (MRCP), coronal and oblique coronal 20mm thick slices. Then, coronal T2w with shorter TE eff, MR-angiography and delayed T1w sequences were performed. CT scan and sonographic examinations of the liver were performed in all patients. Two patients were operated on and 2 underwent endoscopic retrograde cholangiography. RESULTS: Three different types of biliary involvement were found: in 3 cases findings that mimic cholangiocarcinoma spreading along the common bile duct and in 3 other cases multiple smooth extrinsic impressions along the common bile duct; in one patient MRCP demonstrated an irregular narrowing of the common bile duct mimicking chronic cholangitis. In all cases, the bile duct varices appeared of low T2W signal; in three cases, fibrosis was identified on delayed sequences. CONCLUSION: MRCP and MR-angiography can be proposed as a first imaging study in patients with portal cavernoma and cholestasis or bile duct dilatation.     

磁共振胰胆管造影临床应用的价值评价

目的：探讨磁共振胰胆管造影（MRCP）在胆胰疾病中的应用价值。方法：采用重T2加权MR水成像技术对73例患者行MRCP检查。图像经三维最大信号强度投影（3D-MIP）及三维表面遮蔽显示技术（3D-SSD）后处理。结果：73例患者,4例为正常胰胆管,69例胆胰疾病中,梗阻性黄疸者58例,其中恶性胆道梗阻43例,良性胆道梗阻15例,非梗阻性病变11例,在梗阻性黄疸病例中,MRCP定位准确率为100%,并清楚显示扩张胆管程度及断端形态,对于恶性胆阻性病变11例,在梗阻性黄疸病例中,MRCP定位准确率为100%,并清楚显示扩张胆管程度及断端形态。对于恶性胆道梗阻。结合常规MRI可明显提高定性准确率83.7%,同时可显示肿块大小、范围及周围脏器侵犯情况。良性梗阻MR-CP检查的定性准确率为92.9%。在非梗阻性病例中,MRCP可清楚描绘胆囊结石、胆系术后改变及含液丰富的病变（胰腺假性囊肿、总胆管囊肿、十二指肠憩室等）与胰胆管之间的毗邻关系。结论：MRCP可准确揭示胆管梗阻部位,明确病变性质,MRCP对于非梗阻性胆胰疾病则有助于了解病变与周围脏器的毗邻关系。但MRCP作为一种影像检查技术。不能脱离常规CT、MRI,而是对常规影像检查的一种有效补充。     

MR平扫及冠状面LAVA技术在低位胆管梗阻中的诊断价值

目的探讨磁共振平扫[包括磁共振胰胆管造影(MRCP)]及冠状面快速三维容积动态增强(liver acqui-sition with volume acceleration,LAVA)在低位胆管梗阻诊断中的应用价值。资料与方法 64例低位胆管梗阻患者进行MR平扫、MRCP及冠状面LAVA检查,并将检查结果按三种方法分组:(1)平扫(包括MRCP);(2)冠状面LA-VA;(3)MR平扫+冠状面LAVA。对检查结果进行判读与分析,包括病变的定位及定性诊断,并与手术病理、经内镜逆行性胰胆管造影术(ERCP)或经皮肝内胆管造影术(PTC)结果对照,诊断结果进行McNemar检验,数据不足时采用精确概率法。结果依据最终诊断结果将所有病例分为三组:(1)肿瘤性低位胆管梗阻;(2)除结石外良性低位胆管梗阻;(3)结石性低位胆管梗阻。第一组病例中三种方法的定位诊断符合率无统计学差异,而MR平扫的定性诊断符合率低于冠状面LAVA及MR平扫+冠状面LAVA两种方法(P值分别为0.039,0.021)。第二组病例定位及定性诊断符合率无明显统计学差异。第三组冠状面LAVA诊断符合率低于其他两种方法(P=0.031)。结论冠状面LAVA对于肿瘤性低位胆管梗阻的定性诊断具有较大优势,MRCP在胆管梗阻疾病中,简便易行,可用于筛选检查,对于胆管结石的诊断有明显优势。