Icteric-type hepatoma: magnetic resonance imaging and magnetic resonance cholangiographic features

Background: We evaluated the imaging features of magnetic resonance imaging (MRI) and magnetic resonance cholangiography (MRC) of icteric-type hepatoma and correlated these with the findings of endoscopic retrograde cholangiography (ERC), percutaneous cholangiography, and surgery. Methods: Thirteen patients with viral hepatitis complicated by cirrhosis of the liver and obstructive jaundice underwent MRC and dynamic MRI. Five patients received percutaneous transhepatic cholangiography and drainage; one of these patients also underwent resection of the left hepatic lobe. Another patient received MRC followed by thrombectomy and T-tube insertion. ERC and endoscopic nasobiliary drainage were performed in another patient for bile diversion. Results: Primary liver tumors and dilatation of biliary system were demonstrated in all patients. No capsule formation could be found in any primary liver tumors. MRI showed the simultaneous presence of an intraluminal tumor in the portal trunk and common hepatic duct in eight patients. Three different MRC features were found: (a) an oval defect in the hilar bile duct(s) with dilated intrahepatic ducts (n= 9), (b) dilated intrahepatic ducts with missing major bile ducts (n= 2), and (c) localized stricture of the hilar bile duct(s) (n= 2). Conclusion: The presence of one or more of the following features in multiplanar MRI and MRC help to identify this rare, specific type of hepatocellular carcinoma: (a) the presence of an intraluminal tumor in both the portal trunk and the common hepatic duct, (b) enhancement of the intraluminal tumor in the common hepatic duct on the arterial phase, (c) type I MRC feature, and (d) hemobilia, blood clot within the gallbladder, and/or type II MRC feature. Received: 12 January 2000/Revision accepted: 12 July 2000     

Preoperative evaluation of Klatskin tumor: accuracy of spiral CT in determining vascular invasion as a sign of unresectability

Background: To assess the accuracy of spiral computed tomography (CT) in predicting the resectability of Klatskin tumor as determined by vascular invasion. Methods: Twenty-one consecutive patients with Klatskin tumor who had undergone laparotomy were included in this study. The preoperative thin-section (5-mm-thick) spiral CT scans of these patients were assessed for the surgical resectability of tumor by evaluating the vascular invasion. The criterion for vascular invasion indicating unresectability was the tumoral invasion of the proper hepatic artery or main portal vein or simultaneous invasion of one side of the hepatic artery and the other side of the portal vein. Results: All nine patients with tumors thought to be unresectable on the basis of CT findings had tumors that were unresectable at surgery (positive predictive value, 100%). Of 12 patients with tumors thought to be resectable, six had resectable tumors (negative predictive value, 50%). Spiral CT failed to detect small hepatic metastasis (n= 1), lymph node metastasis (n= 1), extensive tumor (n= 2) and variation of bile duct (n= 2), which precluded surgical resection. Conclusion: Spiral CT is a reliable method for detecting vascular invasion and unresectable tumors. However, it has limitations in detecting variations of the bile duct or the intraductal extent of tumor. Received: 24 November 1999/Accepted: 26 January 2000     

Macrocystic serous cystadenoma of the pancreas:CT and endosonographic features

Recently, the term ``serous cystadenoma' has been adopted in the pathological community to qualify the so-called microcystic adenoma of the pancreas. This change in terminology was based on the emergence of a new type of serous cystadenoma of the pancreas, i.e., the macrocystic variant. We report one case of pathologically proven macrocystic serous cystadenoma of the pancreas for which the diagnosis of mucinous cystadenoma was suggested preoperatively. This rare but benign macrocystic variant exhibits radiological features similar to those of mucinous cystadenoma. In addition, inflammatory changes and foci of hemorrhage within the tumor may simulate mucinous cystadenocarcinoma. RID="ID="<e5>Correspondence to:</e5> P. Soyer Received: 25 August 1997/Accepted: 8 October 1997     

Reduction of peristaltic artifacts on magnetic resonance imaging of the abdomen: a comparative evaluation of three drugs

Background: Peristaltic motion is an omnipresent source of degradation in abdominal magnetic resonance (MR) imaging by blurring images and producing ghost artifacts that can mask or mimic lesions. The objective of this study was to select an effective and easy-to-administer drug to provide consistent reduction of peristaltic motion artifacts on MR images. Methods: One hundred forty-eight adult patients with MR examinations of the abdomen were enrolled in a prospective, single-blind comparative study. Four groups were defined: (a) no-drug control group (n = 35), (b) 1 mg of intravenous (IV) glucagon (n = 19), (c) 20 mg of IV butylscopolamine (n = 28), and (d) 20 mg of oral dicyclomine (n = 66). All patients received high-density barium sulphate as a negative oral contrast medium. Quantitative image analysis was performed with operator-defined region-of-interest measurements of signal intensity. Gastrointestinal noise was measured outside the patient at the posterior part of the left hemiabdomen along the phase-encoding direction on a short inversion time inversion recovery (STIR) sequence. Results: Treatment groups showed reduced gastrointestinal noise (p < 0.01). When compared with the control group, IV butylscopolamine (p < 0.05) and oral dicyclomine (p < 0.05) significantly reduced gastrointestinal noise, whereas glucagon did not. Conclusion: Anticholinergic drugs significantly reduced the intensity of ghost artifacts on MR imaging of the abdomen. Twenty milligrams of oral dicyclomine is an effective and safe alternative to more expensive and parenterally administered drugs such as glucagon and butylscopolamine. Received: 22 November 1994/Accepted after revision: 14 March 1995     

Choledochocele: diagnosis by magnetic resonance imaging

The value of magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) is demonstrated in a case of a 22-year-old female with a small choledochocele clinically presenting with acute cholecystitis and pancreatitis. Previous abdominal sonography and computed tomography were not diagnostic. MRI and MRCP showed a cystic dilatation of the distal common bile duct, intramurally located in the second portion of the duodenum and protruding into the duodenal lumen. These findings allowed a confident diagnosis of a choledochocele. Received: 8 December 1999/Accepted: 12 January 2000     

Heterotopic pancreas of the stomach: CT findings correlated with pathologic findings in six patients

Background: The purpose of this study was to characterize the computed tomographic (CT) findings of heterotopic pancreas of the stomach. Methods: CT scans of six surgically proven cases of heterotopic pancreas of the stomach were reviewed. Three were dynamic spiral CT scans, with both arterial dominant and late phase scans. In other three, both unenhanced and contrast-enhanced scans were obtained by using conventional techniques. Particular attention was given to the enhancement of the heterotopic pancreas. Pathologic and surgical findings were correlated with CT findings. Results: The locations were in the gastric antrum in five cases and in the mid-body in one. Size ranged from 1 cm to 3 cm (mean = 2.1 cm). Three cases showed homogeneous, strong enhancement similar to the pancreas and consisted mainly of pancreatic acini with the same histologic features as the normal pancreas. Two cases showed poor enhancement and consisted mainly of ducts and hypertrophied muscle; pancreatic acini were a minor component. In one case appearing as a cystic lesion on CT, a pseudocyst was found with many ducts and some nests of pancreatic acini. Conclusions: Heterotopic pancreas of the stomach showed a diverse spectrum of CT findings. Good understanding of these CT findings may be helpful in making a correct diagnosis. Received: 24 March 1999/Accepted: 19 May 1999     

Lymphoepithelial cysts of the pancreas: CT and sonographic findings

Two cases of rare lymphoepithelial cyst (LEC) of the pancreas are presented. Although the histogenesis of this lesion is not known, it can be histologically differentiated from other pancreatic and retropancreatic cysts. The importance of its recognition is in the distinction from cystic neoplasm of the pancreas. Received: 24 October 1996/Accepted: 27 November 1996     

Isolated ventral pancreatitis in an alcoholic with pancreas divisum

An alcoholic with no history of clinical pancreatitis was found to have pancreas divisum and marked changes of chronic pancreatitis isolated to the ventral pancreas. Pancreas divisum has been suggested to cause recurrent pancreatitis in some patients. Gross and histologic changes of pancreatitis in only the dorsal pancreas of surgically resected specimens from patients with pancreas divisum is thought to support the concept that obstruction at the minor papilla produces dorsal pancreatitis. Alternative explanations for the occurrence of segmental pancreatitis and the possible synergistic role of ethanol and bile are reviewed.     

MR virtual endoscopy of the pancreaticobiliary tract: a feasible technique?

To evaluate the feasibility of magnetic resonance (MR) virtual endoscopy of the pancreaticobiliary tract by using MR cholangiopancreatography (MRCP) data sets as source images, we retrospectively reviewed MRCP data sets of 120 patients with Navigator software (GE/Medical Systems, Milwaukee, WI) that allowed display of inner views by surface rendering the internal wall of the bile ducts with simulated light and shadow. Received: 9 March 1998/Accepted: 8 April 1998     

Hemosuccus pancreaticus: diagnosis with CT and MRI and treatment with transcatheter embolization

We report the case of a 56-year-old woman with a presyncopal episode followed by melena. A sentinel clot sign in the pancreatic duct on precontrast computed tomography and the presence of a splenic artery aneurysm on postcontrast computed tomography strongly suggested a fistula between the aneurysm and the duct, as visualized by magnetic resonance imaging. The patient was treated successfully by complete embolization of the splenic artery aneurysm. Received: 25 January 2000/Accepted: 21 February 2001     

Coexistence of annular pancreas with carcinoma in the dorsal part of pancreas divisum: diagnostic value of magnetic resonance cholangiopancreatography

We report on the incidental observation of a pancreas divisum coexistent with an annular pancreas in a 88-year-old woman presenting with jaundice due to a pancreatic carcinoma. This case report discusses the embryologic hypotheses underlying this peculiar association, highlights the capacities of imaging techniques to depict them, and enhances the performance of magnetic resonance imaging.     

Value of the dynamic and delayed MR sequence with Gd-DTPA in the T-staging of stomach cancer: correlation with the histopathology

Background: To evaluate the usefulness of dynamic and delayed magnetic resonance (MR) imaging in the T-staging of stomach cancer and to compare the enhancement pattern of the cancerous lesion and the normal wall. Methods: We performed MR imaging in 46 patients with stomach cancer (including four early gastric cancers and 42 advanced gastric cancers). Axial, sagittal, or coronal two-dimensional fast low-angle shot) MR images for the water-distended stomach were obtained with dynamic protocol, including precontrast images and images obtained 30, 60, 90, and 240–300 s after intravenous injection of the 0.1 mM Gd-DTPA/kg solution. We evaluated the thickness, interruption (or not) of the low signal intensity bands, and enhancement pattern of the cancerous wall and normal gastric wall. We prospectively evaluated the depth of cancer invasion, perigastric infiltration (extraserosal invasion), perigastric organ invasion, and regional lymph nodes and determined tumor staging on MR images. These MR evaluations including MR-determined staging were correlated with the surgicopathologic findings. Results: Stomach cancer was shown as having a thickened wall with a rapid enhancing pattern after intravenous Gd-DTPA administration. The mucosa (and/or submucosa) affected by stomach cancer showed an early enhancement pattern (30–90 s after Gd-DTPA administration) in 43 of 46 patients (93%). The normal gastric mucosa demonstrated a delayed peak enhancement pattern (>90 s after Gd-DTPA administration) in 29 of 46 patients (63%) and variable enhancement pattern in 17 of 46 patients (37%). An interrupted low signal intensity band or highly enhanced tumorous lesion penetrating through the gastric wall was seen in 17 of 19 pT3 patients (90%). Consistency between MR-determined staging and surgicopathologic staging occurred in three of four pT1 tumors (75%), 10 of 13 pT2 tumors (77%), 17 of 19 pT3 tumors (90%), and eight of 10 pT4 tumors (80%); overall accuracy was 83%. Overall accuracy of regional lymph node involvement, as determined by enhanced MR, was 52%; 24 of 46 node groups were positive. Conclusions: Dynamic and delayed MR imaging can be useful for predicting depth of cancer invasion, perigastric infiltration (extraserosal invasion), and perigastric organ invasion by gastric cancer. Received: 28 July 1998/Revision accepted: 27 January 1999     

Detection of pancreatic adenocarcinoma: relative value of arterial and late phases of spiral CT

Background: Spiral computed tomography (CT) allows the pancreas to be imaged during peak contrast levels owing to the capability of fast data acquisition. The objective of this study was to evaluate the relative value of the arterial and late phases of spiral CT for detecting pancreatic adenocarcinomas. Methods: Twenty-two patients with pathologically proved pancreatic adenocarcinomas underwent two-phase spiral CT. The CT scans were performed with 5 mm collimation and 5 mm/s table speed. Images during the arterial and late phases were obtained at 30- and 180-second delays, respectively. The images of the arterial phase were compared with those of the late phase in terms of tumor conspicuity from surrounding pancreatic parenchyma and tumor detectability by means of a 3-point grading system: 1 (poor), 2 (fair), and 3 (good). Results: In terms of tumor conspicuity from surrounding pancreatic parenchyma, 16 lesions (73%) were good, 5 lesions (23%) were fair, and 1 lesion (4%) was poor during the arterial phase, whereas 6 lesions (27%) were good, 9 lesions (41%) were fair, and 7 lesions (32%) were poor during the late phase (p= 0.0007). The arterial phase was superior to the late phase in 16 patients (73%) and equal in 6 patients (27%). For tumor detectability, 18 lesions (82%) were good, 3 lesions (14%) were fair, and 1 lesion (4%) was poor during the arterial phase, whereas 10 lesions (45%) were good, 7 lesions (32%) were fair, and 5 lesions (23%) were poor during the late phase (p= 0.0033). For detectability, the arterial phase was superior to the late phase in 14 patients (64%) and equal in 8 patients (36%). Conclusion: The arterial phase of spiral CT is superior to the late phase, which is equivalent to conventional CT for detecting pancreatic adenocarcinoma. Received: 1 August 1995/Accepted: 12 September 1995     

Carcinosarcoma of the extrahepatic bile ducts: cholangiographic and CT appearance

A case of histologically proven carcinosarcoma arising in the extrahepatic biliary tree is presented. The tumor appeared on cholangiography and computed tomography as a large expansile intraluminal mass causing biliary obstruction. Received: 19 May 1995/Accepted: 24 June 1995     

Thoracic esophageal carcinoma: evaluation in the sagittal section with magnetic resonance imaging

Among 54 patients with thoracic esophageal carcinoma (53 squamous cell carcinoma, 1 adenosquamous carcinoma), the usefulness of MR sagittal imaging for evaluating local extent (T factor) was examined by measuring the anteroposterior (AP) diameter of the tumor. The MR examination was performed using ECG gated scans with a 3 mm slice at 1.5 Tesla. T1-weighted sagittal images were obtained. In 10 patients the appearance of the esophagus was normal, and in 44 patients a tumor was detected in the sagittal section. Thirty-seven lesions were histologically proved (Tis, 1; T1, 3; T2, 3; T3, 15; T4, 15). Lesions classified as <T2 were not visible, and the appearance of the esophagus was normal. The tumors detected in sagittal section were T3 (15 tumors) or T4 (15 tumors). The mean diameter of T4 lesions (34.0 ± 7.9 mm, range 24–57 mm) was larger than that of T3 lesions (25.0 ± 4.4 mm, range 18–33 mm) (p < 0.05). Only two masses with an AP diameter > 30 mm were resected. They were located in the lower esophagus. It is concluded that lesions detected in MR sagittal images might be T3 or T4 tumors, and masses of >30 mm might extend to adjacent organs, although two tumors with an AP diameter < 25 mm also invaded the trachea. Received: 30 August 1995/Accepted: 10 October 1995     

Abdominal tuberculous lymphadenopathy: MR imaging findings

Background: The purpose of this study was to evaluate the utility of magnetic resonance imaging (MRI) as a diagnostic tool in abdominal tuberculous lymphadenopathy. Methods: MRI studies of 11 patients with histologically proven abdominal tuberculous lymphadenopathy were reviewed with regard to anatomic distribution, size, shape, degree, and pattern of enhancement and relation of the lesions to adjacent structures. Results: The most common site of involvement was the periportal area (n= 6), followed by the peripancreatic (n= 5), mesenteric (n= 1), and paraaortic (n= 1) areas. Eight patients were readily diagnosed as having tuberculous lymphadenopathy on abdominal computed tomography. Three patients had a heterogeneously enhancing masslike lesion adjacent to the pancreas and were initially diagnosed as having cystic tumor of the pancreas. On MRI, 11 lesions showed T1 iso- or hypointensity and central T2 hyperintensity. Two lesions showed T1 iso- or hypointensity and central T2 hypointensity. The lesions with different T2 signal intensities showed different patterns of enhancement on contrast-enhanced dynamic studies. The relations between the enlarged lymph nodes and adjacent bile ducts or vascular structrues were well depicted on MRI. Conclusion: MRI was useful in differentiating enlarged lymph nodes abutting the pancreas initially diagnosed as cystic neoplasms on abdominal computed tomography. RID=" ID=" <E5>Correspondence to:</E5> M.-J. Kim Received: 9 May 2000/Accepted: 14 June 2000     

Diagnostic pitfalls in the cholangiographic diagnosis of choledochoceles: cholangiographic quality and its effect on visualization

Background: We wanted to establish reasonable cholangiographic diagnostic criteria by determining the sensitivity of cholangiography in detecting choledochoceles and those factors that could compromise visualization of choledochoceles. Methods: Over 4 years, 21 patients (seven male, 14 female; mean age = 67 years) were confirmed as having choledochoceles on endoscopic retrograde cholangiopancreatography (ERCP). Cholangiographic diagnosis was made by following three criteria: a radiolucent halo around the distal common bile duct (CBD), bulbous dilatation of the distal CBD, and the presence of sequential morphologic changes on serial cholangiography. Any two or more combinations of these three criteria were considered enough to diagnose a choledochocele on cholangiography. We compared cholangiographic imaging findings with the ERCP results. Results: Of 21 patients with choledochoceles, nine (43%) were correctly diagnosed on cholangiography. A radiolucent halo was present in six (28%) patients; four of these cases showed optimal duodenal filling, one showed faint duodenal filling, and one showed poor duodenal filling. The shapes of the distal CBD were bulbous, conelike, and blunt. Morphologic changes such as collapsing and bulging of the choledochocele could be seen in 12 (57%) patients on serial cholangiography. Waists were seen in 11 (52%), pseudowebs in four (19%), and wrinkling of the distal CBD in seven (33%). Conclusion: Cholangiography should be obtained with optimal timing and adequate conditions to diagnose choledochocele correctly. Received: 20 January 2000/Revision accepted: 31 May 2000     

Pancreatic pleural effusion with a pancreaticopleural fistula diagnosed by magnetic resonance cholangiopancreatography and cured by somatostatin analogue treatment

A 69-year-old man with chronic alcoholic pancreatitis developed a left-sided massive pleural effusion. Magnetic resonance cholangiopancreatography clearly demonstrated the pancreatic cyst and the fistula connecting the cyst with the left pleural cavity, resulting in the diagnosis of pancreatic pleural effusion with a pancreaticopleural fistula. Conservative somatostatin analogue treatment completely eradicated the pancreatic pleural effusion and closed the pancreaticopleural fistula.     

Evaluation of the permeability of pancreaticogastric anastomoses (PGA) with dynamic magnetic resonance pancreatography after secretin stimulation (secretin MRCP)

Background: Because some investigators have reported the systematic occurrence of exocrine pancreatic insufficiency after pancreaticoduodenectomy with pancreaticogastric anastomosis (PGA), we assessed PGA patency after pancreaticoduodenectomy. Methods: Nineteen patients underwent pancreaticoduodenectomy, and their PGAs were studied prospectively with secretin magnetic resonance cholangiopancreatography (MRCP). After administration of negative bowel contrast agent, single-shot fast spin-echo T2-weighted dynamic MR pancreatograms were obtained before and every minute for 12 min after secretin injection. Morphologic features of the pancreatic parenchymal and pancreatic duct were monitored (diameter and winding aspect of the pancreatic duct, pancreatic thickness, direct visualization of the anastomotic site). PGA permeability was classified into four grades, from 0 (obstruction) to 3 (good permeability). Pancreatic function was assessed by fecal-1 elastase concentration, fasting blood glucose, and fasting serum insulin level. Results: MRCP grades were 0 in two patients, 1 in four, 2 in five, and 3 in eight. The anastomotic site was visualized in 10 patients. Pancreatic parenchymal atrophy was discovered in four patients. There were statistically significant relations between secretin MRCP permeability grade and fecal-1 elastase concentration (p < 0.03) and between secretin MRCP permeability grade and pancreatic atrophy (p < 0.005). In contrast, fecal-1 elastase concentration was lower than the normal value in all but one case. There was no statistically significant relation between fecal-1 elastase concentration and other morphologic data. Conclusion: Secretin MRCP may indicate PGA stenosis or dysfunction, but it is not the only factor suggesting exocrine pancreatic insufficiency. Thus the major role of PGA may be the preservation of long-term endocrine function.     

Evaluation of Crohn disease activity with magnetic resonance imaging

Background: The purpose of this study was to assess the accuracy of magnetic resonance imaging (MRI) in evaluating Crohn disease (CD) activity. The intestinal inflammatory activity is usually present in patients under pharmacologic treatment, despite their clinical remission. Methods: Twenty patients with CD, all under pharmacologic treatment, were prospectively studied by MRI at 1.5 T as a periodic control. Positivity of three acute-phase reactants was considered an index of biologic activity (BA). T2-weighted, T2-weighted fat-suppressed turbo spin-echo, and breath-hold T1-weighted turbo field-echo sequences, before and after gadolinium intravenous injection, were obtained. A negative superparamagnetic contrast agent was orally administered. The following MRI parameters were qualitatively evaluated by three radiologists at the level of the affected bowel and compared with clinical data: wall thickness (WT), wall T2-weighted signal (T2W), wall contrast enhancement (WE), amount of fibrofatty proliferation (FP), and T2-weighted signal of fibrofatty proliferation on fat-suppressed images (T2FP). The κ coefficient of agreement was calculated. The Spearman rank correlation was used for the analysis of clinical and radiologic data. Results: Nineteen of 20 patients were in clinical remission (Crohn Disease Activity Index < 150). On the basis of laboratory tests, nine of 20 patients had biologically active disease. An excellent correlation was found between BA and WE, T2W, and T2FP (0.900, 0.927 and 0.961, respectively; p < 0.0001), and a lower correlation was found between BA and WT and between BA and FP (0.78 and 0.62). Excellent statistical correlation was also found between WE and T2W and between WE and T2FP (0.876 and 0.892). Conclusions: An excellent statistical correlation was found between biologically “active” disease and the following MRI parameters: wall gadolinium enhancement, wall hyperintensity on T2-weighted fat-suppressed images, and hyperintensity of fibrofatty proliferation on T2-weighted fat-suppressed images. Therefore, MRI can be valuable in assessing CD activity. Received: 22 January 1999/Revision accepted: 3 November 1999