MR imaging features of primary sclerosing cholangitis: patterns of cirrhosis in relationship to clinical severity of disease

PURPOSE: To evaluate the spectrum of magnetic resonance (MR) imaging appearances of the liver in primary sclerosing cholangitis (PSC) and to examine their correlation with clinical stage of disease. MATERIALS AND METHODS: Fifty-two patients (25 female, 27 male; mean age, 43 years; age range, 11-87 years) with PSC underwent nonenhanced and gadolinium-enhanced MR imaging. Two abdominal radiologists retrospectively reviewed all images (independently and then in consensus) for the imaging pattern of the liver parenchyma, presence and grade of intrahepatic biliary ductal dilatation, and presence of areas of parenchymal atrophy or abnormal signal intensity and/or gadolinium enhancement. Imaging findings were correlated with Child class, Child-Turcotte-Pugh score, and Mayo end-stage liver disease (MELD) score. Statistical analyses (kappa scoring for interobserver agreement, McNemar test, Mann-Whitney U test, multiple regression analysis, Spearman correlation) were performed. RESULTS: Of 52 patients, seven (13%) had no imaging findings of cirrhosis, 17 (33%) had a diffuse pattern of cirrhosis, and 28 (54%) had a large macronodular pattern (with nodules >or=3 cm) (kappa = 0.84). Intrahepatic biliary ductal dilatation was observed in 44 (85%) patients and was general in 18 (35%) and segmental in 26 (50%). Peripheral wedge-shaped areas of parenchyma were observed with atrophy in 23 (44%) and 25 (48%) patients by the two readers (kappa = 0.76) and without atrophy in 18 (35%) patients by both readers (kappa = 1.00). No correlation was found between imaging findings and clinical scores (P >.05, multiple regression analysis; P =.25-.75, Mann-Whitney U test; Spearman correlation coefficients between -0.33 and 0.33). CONCLUSION: The spectrum of MR imaging appearances of PSC is diverse and comprises distinct patterns that do not appear to correlate with severity of disease. Large regenerative nodules are a frequent finding and may help to establish the diagnosis.     

Bone marrow edema and associated pain in early stage osteonecrosis of the femoral head: prospective study with serial MR images

PURPOSE: To determine the accuracy of magnetic resonance (MR) cholangiography for demonstration of the biliary tract and detection of biliary complications in patients who have undergone orthotopic liver transplantation. MATERIALS AND METHODS: Breath-hold half-Fourier rapid acquisition with relaxation enhancement MR cholangiography was performed in 25 patients who had undergone orthotopic liver transplantation. MR cholangiograms were prospectively and independently interpreted by two radiologists for depiction of the biliary tract and ductal anastomosis and for complications (eg, biliary dilatation, stricture, stones). MR cholangiographic findings were correlated with findings from direct cholangiography (n = 24) and surgery (n = 1). RESULTS: MR cholangiography completely demonstrated first-order intrahepatic bile ducts in 23 (92%) patients, the donor extrahepatic bile duct in 25 (100%), the recipient extrahepatic bile duct in 17 of 18 (94%), and the anastomosis in 24 (96%). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of biliary dilatation and stricture were each 100%. Complete interobserver agreement occurred in the detection of biliary dilatation and stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of stones were 100% for one radiologist and 86%, 100%, 96%, 100%, and 95%, respectively, for the other. Both radiologists agreed on the diagnosis of bile duct stones in six of seven cases (kappa = 0.90). CONCLUSION: MR cholangiography enables accurate depiction of the biliary tract and detection of biliary complications in patients with an orthotopic liver transplant.     

Contrast-enhanced MR cholangiography with Gd-EOB-DTPA in patients with liver cirrhosis: visualization of the biliary ducts in comparison with patients with normal liver parenchyma

The purpose of this study was to assess the quality of biliary duct visualization using Gd-EOB-DTPA-enhanced magnetic resonance cholangiography (EOB-MRC) in patients with liver cirrhosis. Forty adult patients with liver cirrhosis (cirrhosis group) and 20 adult individuals with normal liver parenchyma (control group) underwent EOB-MRC using T1-weighted GRE imaging up to 180 min after Gd-EOB-DTPA administration. Two observers assessed the visualization of each biliary structure and the overall anatomical visualization of the biliary tree. Child-Pugh, MELD score and laboratory findings were compared. The grade of visualization for each evaluated biliary structure was statistically different in the two groups (P = 0.004 to <0.001). The overall EOB-MRC quality was rated as sufficient for anatomical visualization of the biliary tree in all individuals of the control group 20 min after Gd-EOB-DTPA application, but in only 16/40 patients (40%) of the cirrhosis group within 30 min after application. Analysis of the ROC curves revealed that the cut-off values, for non-sufficient visualization of the biliary tree 20 min after Gd-EOB-DTPA application, were MELD scores > or =11 and total serum bilirubin levels > or =30 micromol/l. Consecutively, EOB-MRC in patients with liver cirrhosis resulted in a decreased or even non-visualization of the biliary tree in a substantial percentage of patients.     

Overlap syndrome of autoimmune chronic liver diseases: MRI findings

Purpose:

To describe the MR findings of overlap syndromes of autoimmune chronic liver diseases.

Methods:

Review of clinical and radiological databases between March 2001 and July 2008 for patients with a clinical diagnosis and liver biopsy features compatible with overlap syndrome who had also undergone an abdominal MRI yielded 15 adult patients. MR features of overlap syndrome were reviewed by two radiologists by consensus. Two radiologists independently reviewed the studies in a blinded fashion for primary sclerosing cholangitis (PSC)‐type or non‐PSC‐type features to assess interobserver agreement.

Results:

PSC‐type and non‐PSC‐type overlap syndrome had distinctive MR features. In the consensus review, all 12 patients with PSC‐type overlap syndrome were correctly identified. Imaging findings included central macroregeneration (N = 9), peripheral atrophy (N = 7), biliary duct beading (N = 12), biliary dilation (N = 10), or a combination of all four findings (N = 7). The presence of any of the first three features had 100% specificity for a PSC‐type overlap syndrome. Patients with non‐PSC‐type overlap (N = 3) showed relatively normal liver morphology (N = 3) and minimal biliary ductal dilatation in one patient. There was good interobserver agreement (kappa = 0.76).

Conclusion:

Patients with serologic or pathologic evidence of AIH or PBC with imaging features of PSC may have PSC‐type overlap syndrome. J. Magn. Reson. Imaging 2010; 31: 383–389. © 2010 Wiley‐Liss, Inc.     

Chemotherapy-induced sclerosing cholangitis

AIM: To review the computed tomography (CT), magnetic resonance imaging (MRI) and cholangiographic findings of chemotherapy-induced sclerosing cholangitis (CISC). METHODS: Between January 1995 and December 2004, 11 patients in the endoscopic retrograde cholangiography database were identified with CISC. Twelve CT, four MRI, 69 endoscopic and nine antegrade cholangiographic studies in these patients were reviewed. Serial change in appearance and response to endoscopic treatment were recorded. RESULTS: CISC showed segmental irregular biliary dilatation with strictures of proximal extrahepatic bile ducts. The distal 5cm of common bile duct was not affected in any patient. CT and MRI findings included altered vascular perfusion of one or more liver segments, liver metastases or peritoneal carcinomatosis. Biliary strictures needed repeated stenting in 10 patients (mean: every 4.7 months). Cirrhosis (n=1) or confluent fibrosis (n=0) were uncommon findings. CONCLUSION: CISC shares similar cholangiographic appearances to primary sclerosing cholangitis (PSC). Unlike PSC, biliary disease primarily involved ducts at the hepatic porta rather than intrahepatic ducts. Multiphasic contrast-enhanced CT or MRI may show evidence of perfusion abnormalities, cavitary liver lesions, or metastatic disease.     

Contrast-enhanced MRI combined with MR cholangiopancreatography for the evaluation of patients with biliary strictures: differentiation of malignant from benign bile duct strictures

PURPOSE: To determine imaging criteria for the combined use of contrast-enhanced (CE)-MRI and MR cholangiopancreatography (MRCP) to differentiate malignant from benign biliary strictures. MATERIALS AND METHODS: A total of 44 patients with biliary stricture who had undergone unenhanced, MRCP, and dynamic MRI were identified from radiological and surgical databases. Two radiologists analyzed MR features for asymmetry, luminal irregularity, abrupt narrowing, outer margin, signal intensity (SI) on T2-weighted (T2W) images, and hyperenhancement relative to liver parenchyma during portal phase. The wall thickness and length of the narrowed segment were measured. MR findings relevant as predictors were identified using a Chi-square or Fisher's exact test and the odds ratio (OR). RESULTS: The presence of hyperenhancement relative to liver parenchyma, length > 12 mm, wall thickness > 3 mm, indistinct outer margin, luminal irregularity, and asymmetry of strictured bile duct were significant factors for malignancy (P < 0.05). Malignant strictures were significantly thicker (5.0 +/- 2.0 mm) and longer (27.0 +/- 13.6 mm) than benign strictures. When any three or more of these six criteria were used in combination, we could identify 100% of malignant strictures and 87.0% of benign strictures. CONCLUSION: The combined use of CE-MRI and MRCP helped to define the criteria for differentiating malignant from benign biliary strictures in our data.     

Abdominal extrapancreatic lesions associated with autoimmune pancreatitis: radiological findings and changes after therapy

PURPOSE: To evaluate imaging findings of abdominal extrapancreatic lesions associated with autoimmune pancreatitis (AIP) and changes after steroid therapy. METHODS AND MATERIALS: This study included nine AIP patients with abdominal extrapancreatic lesions, which were determined by retrospective radiological review. CT (initial and follow-up, n=9) and MR imaging (initial, n=5) were reviewed by two radiologists in consensus to determine imaging characteristics (i.e., size, number, attenuation or signal intensity, and contrast enhancement of the lesions, and the presence of overlying capsule retraction) and evaluate changes with steroid therapy of abdominal extrapancreatic lesions associated with AIP. RESULTS: The most common abdominal extrapancreatic lesion associated with AIP was retroperitoneal fibrosis (RPF) in six patients. In five patients, CT and MR imaging revealed single or multiple, round- or wedge-shaped, hypoattenuating or hypointense, enhancing lesions in the renal cortex or pelvis. Other lesions included a geographic, ill-defined, hypoattenuating lesion with or without overlying capsule retraction in the liver in two and bile duct dilatation with or without bile duct wall thickening in four. Over a follow-up period of 6-81 months, CT exams of eight patients demonstrated partial or complete improvement of the abdominal extrapancreatic lesions, albeit their improvement in general lagged behind that of the pancreatic lesion. CONCLUSION: On CT or MR imaging, the abdominal extrapancreatic lesions associated with AIP are various in the retroperitoneum, liver, kidneys and bile ducts, and are reversible with steroid therapy.     

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.     

Chronic hypersensitivity pneumonitis: CT features comparison with pathologic evidence of fibrosis and survival

PURPOSE: To retrospectively compare in patients with chronic hypersensitivity pneumonitis (HP) the computed tomographic (CT) imaging features suggestive of fibrosis with pathologic evidence of fibrosis at surgical lung biopsy and to compare a usual interstitial pneumonia (UIP) pattern at CT with survival. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for this study, which was HIPAA compliant. Twenty-six patients (15 women, 11 men; age range, 37-76 years) with chronic HP had their surgical lung biopsy results reviewed by two pathologists for the presence of fibrosis. Two radiologists systematically reviewed the CT scans. The two radiologists were blinded to all clinical information, including pathologic diagnosis, patient information, and outcomes. The combination of a subpleural reticular pattern and lower zone predominance was considered a UIP pattern. CT findings were compared with the histopathologic presence of fibrosis, physiologic parameters, symptoms, and survival. The chi(2) or Fisher exact test (each two-tailed) was used to compare nominal and ordinal variables. A t test (with unequal variances) was used to compare continuous variables. The log-rank procedure was used to compare Kaplan-Meier survival curves. RESULTS: Fifteen patients had fibrotic HP at biopsy, and 11 had nonfibrotic HP. Patients with fibrotic HP had more extensive reticular pattern and were more likely to have traction bronchiectasis, honeycombing, and a UIP pattern than those with nonfibrotic HP (P = .015, P = .007, P = .007, respectively). Although the presence of histologic fibrosis was associated with decreased survival (P = .003), the CT features were not associated with decreased survival. CONCLUSION: CT findings of extensive reticular pattern, traction bronchiectasis, and honeycombing are closely related to the presence of histologic fibrosis in chronic HP.     

MR imaging findings of early bile duct cancer

Purpose

To retrospectively evaluate the MR imaging features of early bile duct cancer and to correlate them with the clinicopathologic findings.

Materials and Methods

This retrospective study was approved by our institutional review board, and informed consent was waived. Seventeen patients with surgically proven early bile duct cancer who had undergone preoperative MR cholangiopancreatography with gadolinium‐enhanced MR imaging, were included in this study. Two, experienced radiologists evaluated the MR images in consensus regarding the following findings: tumor number and morphology; signal intensity of the tumor; sharpness of the outer border of the bile duct wall; enhancement pattern of the tumor; and the presence of enlarged peribiliary lymph nodes. Another radiologist measured the SNR of the tumor and bile duct wall on gadolinium‐enhanced MRI during the dynamic phases to evaluate the tumor enhancement degree.

Results

In all patients, MR imaging demonstrated single or multiple intraluminal bile duct masses showing a sharply defined outer margin. The most common enhancement pattern of the biliary lesions showed heterogeneous amorphous enhancement or heterogeneous enhancement with central, dot‐like structures or vascular structures (76.5%, 13/17 patients). The difference of SNR between bile duct and tumor was greatest in the equilibrium phase (P < 0.05).

Conclusion

MRCP combined with dynamic contrast‐enhanced MRI can be useful for detecting early bile duct cancers. Common MR findings of early bile duct cancer include one or more inhomogeneously enhancing intraductal masses with clear outer margins and preservation of the bile duct wall. J. Magn. Reson. Imaging 2008;28:1466–1475. © 2008 Wiley‐Liss, Inc.     

Esophageal varices: diagnosis with gadolinium-enhanced MR imaging of the liver for patients with chronic liver damage

OBJECTIVE: The purpose of our study was to evaluate the value of gadolinium-enhanced MR imaging of the liver in the detection and grading of esophageal varices in patients with chronic liver damage. MATERIALS AND METHODS: Three independent off-site radiologists retrospectively reviewed MR images of the liver obtained in 72 patients with chronic liver damage, including 49 patients with untreated esophageal varices. All patients had undergone gastrointestinal endoscopy within 2 weeks of MR imaging. Both MR and endoscopic images were reviewed to determine whether esophageal varices were present and, if so, to determine the grade of the varices. Observer performances were tested with receiver operating characteristic curve analysis using the jackknife dispersion test. Correlations between the grades of the varices determined using MR images and those determined using endoscopic images were tested. RESULTS: Sensitivity for detection of esophageal varices was significantly (p < 0.01) higher for the combination of unenhanced and gadolinium-enhanced MR images (81%) than for the unenhanced MR images alone (51%). The receiver operating characteristic curve analysis (area under the curve, [A(z)]) showed that performance using the combination of the unenhanced and gadolinium-enhanced MR images (A(z) = 0.641) was superior to that using unenhanced MR images alone (A(z) = 0.586). A statistically significant positive correlation (p < 0.05) was found between the grades determined using MR imaging and the grades determined using endoscopy. CONCLUSION: Our results suggest the potential value of diagnosing the presence and grade of esophageal varices on MR imaging of the liver for patients with chronic liver damage. Gadolinium-enhanced MR imaging may increase the potential value.     

Right lobe living donor liver transplantation: preoperative evaluation of the donor with MR imaging

OBJECTIVE: The purpose of this study was to report our experience in preoperative evaluation of right hepatic lobe donors with a comprehensive MR examination and to compare abdominal MR images, MR cholangiograms, and MR angiograms with findings at surgery, intraoperative cholangiography, and digital subtraction angiography. MATERIALS AND METHODS: Twenty-eight right hepatic lobe donors underwent preoperative evaluation with MR imaging, MR cholangiography, and MR angiography. Two abdominal radiologists independently and randomly reviewed these studies. Points of assessment included focal and diffuse liver disease, calculation of right lobe volumes, depiction of the biliary tract and ductal anomalies, and depiction of the liver vasculature and vascular anomalies. Comparison was made with intraoperative cholangiograms (n = 20) and digital subtraction angiograms (n = 28). RESULTS: MR imaging revealed and characterized focal liver lesions in eight of 28 patients. Calculated right lobe volumes agreed with surgically determined volumes within 7% for reviewer 1 and within 15% for reviewer 2. Intrahepatic bile ducts were depicted completely with MR cholangiography in 25 of 28 patients and with intraoperative cholangiography in nine of 20 patients. MR cholangiography revealed ductal anomalies in six patients. MR imaging and MR angiography depicted the portal veins more completely than digital subtraction angiography. MR imaging and MR angiography correctly excluded portal venous anomalies in all patients and revealed surgically confirmed accessory hepatic veins in six of 28 patients. Angiographically confirmed arterial anomalies were correctly detected in three of 28 patients by at least one reviewer on MR imaging and MR angiography. CONCLUSION: MR imaging, MR cholangiography, and MR angiography provide a comprehensive, accurate means of evaluating donors for factors that may preclude or complicate right hepatic lobe donation.     

移植肝排斥反应血管和胆管改变的MR表现

目的：探讨磁共振血管造影（MRA）和胰胆管成像（MRCP）对诊断肝移植术后排斥反应的价值。方法：6例原位肝移植术（OLT）后排斥反应患者均用磁共振（MR）快速自旋回波（TSE）序列及快速小角度激发梯度回波（FLASH）序列常规扫描、磁共振胆管成像（MRCP）、钆喷替酸葡甲胺（Gd-DTPA）动态增强3D MRA检查,分析各序列图像特点。结果：①形态和信号改变：6例患者均有肝脏体积增大,饱满。仅1例重度急性排斥反应患者肝实质信号异常;②血管异常表现：1例急性排斥反应肝左动脉串珠样改变及供体段门静脉明显变细。1例急性排斥反应肝静脉末梢分支杵状扩张而下腔静脉吻合口通畅。其余4例血管无明显异常表现;③胆管异常表现：4例急性排斥反应患者肝内胆管纤细稀疏,1例肝内胆管未显影,1例无明显异常表现。3例慢性排斥反应患者中2例肝内胆管分支稀疏并左肝管串珠样改变;1例胆总管胆泥形成而肝内胆管未见扩张。结论：肝移植术后排斥反应有一些特征性的血管和胆管MR表现。磁共振血管造影和胆管造影作为一种非侵袭性影像检查方法,可以辅助临床诊断肝移植术后排斥反应。     

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 imaging as the sole preoperative imaging modality for right hepatectomy: a prospective study of living adult-to-adult liver donor candidates

OBJECTIVE: Our aim was to investigate the feasibility of MR imaging as a comprehensive preoperative imaging test for examination of liver donor candidates for adult-to-adult right lobe transplantation. SUBJECTS AND METHODS: Twenty-five consecutive donor candidates were examined at 1.5 T using a torso phased array coil with breath-hold T1- and T2-weighted imaging of the abdomen, MR cholangiography using T2-weighted turbo spin-echo imaging, and MR angiography and venography of the liver using two interpolated three-dimensional spoiled gradient-echo sequences (average dose of gadolinium contrast material, 0.17 mmol/kg). Images were interpreted for liver parenchymal and extrahepatic abnormalities; measurements of right and left lobe liver volumes; definition of hepatic arterial, portal venous, and hepatic venous anatomy; and definition of the biliary branching pattern. Findings were compared with those of conventional angiography in 13 patients, 11 of whom also had surgical findings for comparison. RESULTS: Nine patients were excluded as candidates for donation on the basis of MR imaging findings that included parenchymal or extrahepatic abnormalities in five patients, vascular anomalies in two, and biliary anomalies in three. Two patients who did not undergo surgery underwent conventional angiography that confirmed MR angiographic findings except for a small (<2 mm) accessory left hepatic artery missed on MR imaging. Of the nine patients who underwent successful right hepatectomy, all MR imaging findings were corroborated intraoperatively. In two patients, right hepatectomy was aborted at laparotomy because of intraoperative cholangiography findings; in one of them, the biliary finding was unsuspected on MR imaging. CONCLUSION: A comprehensive MR imaging examination has the potential to serve as the sole preoperative imaging modality for living adult-to-adult liver donor candidates provided improvements in definition of intrahepatic biliary anatomy can be achieved.     

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.     

Primary sclerosing cholangitis: MR imaging findings with pathologic correlation.

OBJECTIVE: The purpose of this study was to evaluate MR imaging findings of primary sclerosing cholangitis, to compare them with histopathologic findings, and to determine if these findings help differentiate primary sclerosing cholangitis from other disorders that result in end-stage liver disease. MATERIALS AND METHODS: MR imaging was performed in 40 patients (27 men, 13 women; age range, 13-72 years; mean, 47 years) with primary sclerosing cholangitis over a 9-year period. In 16 patients who underwent orthotopic hepatic transplantation and in seven patients who underwent needle biopsy, correlation was made between MR imaging and pathologic findings. RESULTS: Focal signal changes in the liver parenchyma were seen on T2-weighted images as peripheral wedge-shaped zones of increased signal intensity in 29 patients (72%), as a reticular pattern in 15 patients (38%), and as periportal edema in 16 patients (40%). Lobar atrophy involved the right lobe in three patients (8%) and the left lobe in 11 patients (28%); hypertrophy of the caudate lobe was seen in nine patients (23%). Features of portal hypertension were seen in 14 patients (35%). Histologic assessment showed zones of segmental atrophy and scarring on the periphery of the liver. CONCLUSION: Peripheral wedge-shaped areas of high T2 signal intensity and dilatation of bile ducts are characteristic MR features of primary sclerosing cholangitis. Pathologic correlation suggests that these features may be related to underlying perfusion changes and bile duct inflammation in patients with primary sclerosing cholangitis.     

Biliary tract depiction in living potential liver donors: comparison of conventional MR, mangafodipir trisodium-enhanced excretory MR, and multi-detector row CT cholangiography--initial experience

PURPOSE: To compare biliary tract depiction in living potential liver donors at conventional magnetic resonance (MR), mangafodipir trisodium-enhanced excretory MR, and multi-detector row computed tomographic (CT) cholangiography. MATERIALS AND METHODS: Eight living potential liver donors underwent iodipamide meglumine-enhanced CT cholangiography. Eight different potential liver donors then underwent conventional MR cholangiography and mangafodipir trisodium-enhanced excretory MR cholangiography. Two readers independently scored all first-, second-, and third-order biliary branches with a four-point scale from 0 (not seen) to 3 (excellent visualization). Interobserver agreement was calculated by using the weighted kappa statistic. Scores were compared between imaging modalities by using generalized estimating equations. Imaging findings of second-order biliary tract anatomy were compared with intraoperative findings for nine patients. RESULTS: Interobserver agreement for overall biliary tract visualization was good for CT, conventional MR, and excretory MR cholangiography (with weighted kappa values of 0.76, 0.66, and 0.79, respectively). The mean second-order biliary branch visualization scores for readers 1 and 2, respectively, were significantly higher at CT cholangiography (2.81 and 2.75) than at conventional MR (1.84 and 1.75, P <.001), excretory MR (2.00 and 2.06, P <.001), and combined conventional and excretory MR cholangiography (2.31 and 2.25, P <.01). At CT, conventional MR, and excretory MR cholangiography, respectively, second-order biliary branching anatomy was discernible in eight, five, and seven patients, with second-order biliary branch variants seen in three, two, and two patients. Surgical findings confirmed the pattern of second-order biliary branching seen at CT in five patients, that seen at conventional MR imaging in one patient, and that seen at excretory MR cholangiography in three patients. At surgery, one case of variant biliary anatomy was found to have been missed at CT cholangiography. CONCLUSION: In living potential liver donors, CT cholangiography enables significantly better biliary tract visualization than conventional or excretory MR cholangiography either alone or in combination.     

Autoimmune pancreatitis: imaging features

PURPOSE: To retrospectively determine imaging findings in patients with autoimmune pancreatitis. MATERIALS AND METHODS: Twenty-nine patients (25 male and four female; mean age, 56 years; range, 15-82 years) with histopathologic diagnosis of autoimmune pancreatitis were examined. Data were reviewed by two radiologists in consensus. Imaging findings for review included those from helical computed tomography (CT), 25 patients; magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP), four patients; endoscopic ultrasonography (US), 21 patients; endoscopic retrograde cholangiopancreatography (ERCP), 19 patients; and percutaneous transhepatic cholangiography, one patient. Images were analyzed for appearances of pancreas, biliary and pancreatic ducts, and other findings, such as peripancreatic inflammation, encasement of vessels, mass effect, pancreatic calcification, peripancreatic nodes, and peripancreatic fluid collection. Follow-up images were available in nine patients. Serologic markers such as serum immunoglobulin G (IgG) and antinuclear antibody levels were available in 12 patients. RESULTS: CT showed diffuse (n = 14) and focal (n = 7) enlargement of pancreas. Seven patients had minimal peripancreatic stranding, with lack of vascular encasement, calcification, or peripancreatic fluid collection. Nine patients had enlarged peripancreatic lymph nodes. MR imaging showed focal (n = 2) and diffuse (n = 2) enlargement with rimlike enhancement in one. MRCP revealed pancreatic duct strictures in two and sclerosing cholangitis-like appearance in one. Endoscopic US showed diffuse enlargement of pancreas with altered echotexture in 13 patients and focal mass in the head in six. ERCP showed stricture of distal common bile duct in 12 patients, irregular narrowing of intrahepatic ducts in six, diffuse irregular narrowing of pancreatic duct in nine, and focal stricture of proximal pancreatic duct in six. Serologic markers showed increased IgG and antinuclear antibody levels in seven of 12 patients. At follow-up, CT abnormalities and common bile duct strictures resolved after steroid therapy in three patients. CONCLUSION: Features that suggest autoimmune pancreatitis include focal or diffuse pancreatic enlargement, with minimal peripancreatic inflammation and absence of vascular encasement or calcification at CT and endoscopic US, and diffuse irregular narrowing of main pancreatic duct, with associated multiple biliary strictures at ERCP.     

自身免疫性肝病重叠综合征的 MR 表现

目的：探讨自身免疫性肝病重叠综合征的MR表现及其诊断价值。方法收集7例病理确诊的自身免疫性肝病重叠综合征患者,并对其行M R检查,扫描序列包括T1 WI、T2 WI、DWI、M RCP。2位有经验的影像诊断医师单盲方法独立阅读每位患者的影像资料。结果自身免疫性肝炎（AIH）／原发性胆汁性肝炎（PBC）4例、AIH／原发性硬化性胆管炎（PSC）1例、PBC／PSC 1例、AIH／PBC／PSC 1例。AIH／PBC同时具备AIH和PBC的影像学特征,AIH／PSC同时具备AIH和 PSC的影像学特征,PBC／PSC同时具备PBC和PSC的影像学特征,AIH／PBC／PSC同时具备AIH、PBC和PSC的影像学特征。结论当某一种自身免疫性肝病患者同时具有其他类型自身免疫性肝病的影像学特征时,考虑此患者已发展为自身免疫性肝病重叠综合征。