Spiral CT of the abdomen after distention of small bowel loops with transparent enema in patients with Crohn's disease

Background: To evaluate the capability of a computed tomographic (CT) technique that combines distention of the small bowel loops with a transparent enema with contrast-enhanced spiral CT of the abdomen in patients with Crohn's disease. Methods: We evaluated the abdomen with spiral CT after distention of the small bowel loops with a transparent enema of methylcellulose in 40 patients consecutively referred for radiologic evaluation of Crohn's disease of the small bowel. Fluid was infused through a nasojejunal catheter with a peristaltic pump. Ultrasonography was used to prevent bowel overdistention and detect arrival of methylcellulose to the cecum. Contrast-enhanced spiral CT of the abdomen was then performed, and the degree of contrast enhancement and the thickness of the walls of the involved loops were evaluated. A series of 10 patients with retrograde distention of the last ileal loop from large bowel water enema was used as a control. The results of the CT were compared with those of conventional radiographic small bowel studies. Results: The normal small bowel wall was 1.9–2.5 mm thick (mean = 2.1 mm); density values of the normal enhanced wall varied between 25 and 60 HU (mean = 32 HU) and presented a homogeneous structure. Bowel segments involved by the disease were 4–12.5 mm thick (mean = 9.2 mm), had density values of 75–150 HU (mean = 105 HU), and showed a multilayered appearance. Compared with conventional radiography, CT detected longer lesions or additional segments involved by the disease process in 14 cases, 11 additional fistulas, two abscesses, and mesenteric changes in 21 cases. Conclusions: The small bowel CT enema technique provides good results in the study of patients with Crohn's disease and can be used to evaluate patients with advanced lesions. Received: 24 June 1998/Revision accepted: 27 January 1999     

Enteroclysis findings of intestinal Behcet disease: a comparative study with Crohn disease

Background: The aim of this study was threefold; to define the enteroclysis (EC) findings of intestinal involvement in Behcet disease (BD), to compare these findings with those seen in Crohn disease (CD), and to determine the relation between the duration of BD and severity of the EC findings. Methods: From 1997 to 2000, 17 BD and 50 CD cases were examined by EC examination. EC was performed with a 13-F balloon catheter via transnasal entubation. Mucosal and mural changes were evaluated. Statistical analysis was performed with the Mann-Whitney U test to determine the relation between duration of BD and severity of the EC findings. P ≤ 0.05 was considered statistically significant. Results: In 12 (70.58%) of 17 BD cases, EC demonstrated intestinal pathologic findings such as ulcerations, fold thickening, granular pattern, pseudopolyp formation, and bowel wall thickening. No statistical correlation between the severity of EC findings and the duration of BD was found. Conclusion: EC should be the radiologic method to evaluate the intestinal pathology in symptomatic BD patients. The main EC finding in BD was ulceration mostly in the aphthous form. The EC findings in BD, even in longstanding cases, are usually mild when compared with those seen in CD.     

Primary small bowel tumors: a radiologic-pathologic correlation

Background: Primary small bowel tumors are rare and their preoperative diagnosis is unsatisfactory. The cornerstone of diagnosis remains contrast radiography. The present study was done to evaluate the radiologic findings of primary small bowel tumors as shown on enteroclysis and to correlate these observations with surgical and histopathologic findings. Methods: Seventy two patients with primary small bowel tumors identified by enteroclysis were evaluated. All the patients were subjected to jejunal biopsy or surgery. The diagnosis was established by histopathologic examination in all cases. Results: Radiologic findings were suggestive of benign tumors in 19 patients and malignant tumors in 31 patients. Nonspecific findings in the form of diffuse involvement of the small bowel were noted in 22 patients. There was 100% radiologic–surgical correlation. Leiomyomas and lymphomas were the most common benign and malignant tumors, respectively. Tumor specificities were 89.5% for benign tumors and 41.5% for malignant tumors. Conclusion: Distinctive morphologic patterns as shown on enteroclysis are highly suggestive of specific tumor types in the majority of cases. Received: 25 April 2000/Revision accepted: 20 September 2000     

Current status of small bowel radiography

Background: In the past, small bowel examinations were usually ordered for the sake of ``completeness.' As a result, small bowel radiography was performed casually and without attention to detail. This review examines pertinent clinical issues and the recent contribution of small bowel radiography to the evaluation and management of the patient with suspected small bowel disease. Recommendations for the clinical utilization of small bowel radiography are discussed. Methods: Analysis of pertinent citations addressing valid indications for, and technique of, small bowel radiography from 1980 to July 1995 through a computerized bibliographic search (Medline and Current Contents). Results: Accepted clinical indications for small bowel radiography include (1) unexplained gastrointestinal bleeding, (2) possible small bowel tumor, (3) small bowel obstruction, (4) Crohn disease, and (5) malabsorption. The current literature reflects the limitations of the conventional small bowel follow-through, various modifications to improve its clinical yield, the important contribution of enteroclysis in the workup, and subsequent management of patients with possible small bowel disease. A controversy in the radiology literature exists as to whether to use the small bowel follow-through or enteroclysis as the primary method of examining the small bowel. Conclusion: The thoughtful selection of patients by clinicians for small bowel radiography is essential to make radiologic evaluation cost effective. The incidence of disease of the small intestine is low and is associated with nonspecific symptoms. Because of the inherent difficulty of visualizing numerous loops of an actively peristalsing bowel, a reliable imaging method is needed that not only detects small or early structural abnormality but also accurately documents normalcy. The yield of information provided by enteroclysis and its high negative predictive value suggests that it should be the primary method for small bowel examination. The ``overhead'-based conventional small bowel follow-through should be abandoned. The ``fluoroscopy'-based small bowel follow-through augmented when necessary by the peroral pneumocolon or the gas-enhanced double-contrast follow-through method is an acceptable alternative when enteroclysis is not possible. Received: 0/0/00Accepted: 0/0/00     

Adult Crohn disease: can ileoscopy replace small bowel radiology?

Background: This study aimed to document the radiological features and distribution of small bowel Crohn disease (CD) in adults by using a barium follow-through (BaFT) technique and to determine whether disease would be missed or its distribution underestimated if only colonoscopy with ileoscopy were performed. Methods: The BaFT examinations of 121 adults with proven CD were reviewed retrospectively with respect to the stage and distribution of disease. Colonoscopy with attempted ileoscopy was performed in 37 of these subjects, and the results were compared with radiological findings. Results: A normal villous pattern was visualized in 89 studies (74%). BaFT showed small bowel CD in 71 (59%) of 121 patients studied. The terminal ileum (TI) was the most common site of disease, affecting 62 (87%) of patients with small bowel CD. Forty-six patients (65%) had more proximal small bowel disease, including nine (13%) with a normal TI. BaFT showed early mucosal changes of CD in 52 subjects (73%), which was the sole manifestation in 15 (21%). Ileoscopy was possible in the majority of patients colonoscoped but was not achieved in 14 (38%), nine of whom had CD on BaFT. Of the 23 patients in whom ileoscopy was performed, findings agreed with BaFT assessment of the TI in 22. Conclusion: BaFT adequately demonstrates the stage and extent of small bowel CD. The majority of patients with small bowel CD have disease proximal to the TI, which cannot be diagnosed by ileoscopy. Received: 27 August 1996/Accepted: 16 October 1996     

Pirenzepine versus scopolamine methyl bromide in double-contrast barium enema study of large bowel

To evaluate the usefulness of pirenzepine for diagnostic double-contrast barium enema study of the large bowel, pirenzepine and scopolamine methyl bromide (SMB) were compared in a single, blind, randomized trial. Sixty consecutive patients were enrolled in the study. Quantitative analysis of bowel distention was done by measuring the maximum diameter of the transverse colon before and after drug administration. Four independent observers blindly evaluated distention and mucosal coating of the large bowel and global quality of the images. No differences were found in the diagnostic performance between the two drugs. However, pirenzepine induced a slight but significantly larger distention of the large bowel (68 ± 12 vs. 65 ± 8 mm, p= 0.02). Heart rate and rhythm during the study were recorded by ECG. SMB induced tachycardia in all patients (from 72 ± 15 to 98 ± 24 beats/min, p < 0.01), whereas pirenzepine did not (from 76 ± 13 to 78 ± 20, p= NS). After SMB, one-patient exhibited faintness, and some patients complained of visual accommodation defects, dryness of the mouth, and dizziness. Pirenzepine had a diagnostic performance similar to SMB in avoiding adverse effects elicited by SMB. Received: 14 December 1994/Accepted: 2 February 1995     

Comparison of capsule endoscopy with enteroclysis in the investigation of small bowel disease

Purpose  To compare results of capsule endoscopy with those of barium enteroclysis or CT enteroclysis. Methods  Retrospective review of hospital records revealed 65 patients who had an enteroclysis and small bowel capsule endoscopy. The diagnostic yield of capsule endoscopy was compared with the enteroclysis using Fisher’s exact test. Results  The main indications were obscure gastrointestinal bleeding (n = 37) and suspected Crohn disease (n = 17). Radiologic studies included CT enteroclysis (n = 30), and fluoroscopic barium enteroclysis with carbon dioxide (n = 18) or with methylcellulose (n = 17). Capsule endoscopy had a higher diagnostic yield (8/17) compared to barium–methylcellulose cellulose enteroclysis (1/17) (P = 0.02). The diagnostic yield of capsule endoscopy was not significantly different compared with barium–carbon dioxide (12/18 vs. 10/18) enteroclysis or with CT enteroclysis (9/30 vs. 8/30). Vascular lesions were better assessed with capsule endoscopy. However, the CT enteroclysis found more lesions in patients with chronic abdominal pain. Conclusion  Barium–carbon dioxide enteroclysis and CT enteroclysis have similar diagnostic yields for small bowel disease compared to capsule endoscopy. Barium methylcellulose has an inferior diagnostic yield.     

Amyloidosis of the alimentary canal: radiologic–pathologic correlation of CT findings

Background: The purpose of the study was to describe the computed tomographic (CT) findings of the alimentary canal and mesentery in amyloid infiltration of the gastrointestinal (GI) tract and to correlate the CT findings with histologic extent and distribution and with amyloid subtype. Methods: Abdominal CT scans performed between 1988 and 1997 on patients with pathologically proven amyloidosis of the alimentary canal were reviewed for abnormalities of the alimentary canal and mesentery. Histology was graded for extent of mucosal, submucosal, and muscularis propria involvement and for degree of interstitial and vascular distribution. CT findings were correlated with histologic extent, histologic distribution, and amyloid histochemical type. Results: Twenty-three patients were included. Four (17%) had bowel wall thickening, which was associated with a higher submucosal extent and interstitial distribution than in patients with normal bowel by CT. Four (17%) patients had bowel wall dilatation without thickening, which was not associated with statistically significantly different histology than in patients with normal bowel by CT. There was no statistically significant correlation between CT findings and histochemical subtype. Mesenteric soft tissue infiltration was seen in two patients, and mesenteric adenopathy was seen in one patient. Conclusions: Normal bowel is a common abdominal CT finding in amyloidosis of the alimentary canal. When findings are present, GI wall thickening and/or bowel wall dilatation without wall thickening may be seen. Bowel wall thickening on CT correlates with submucosal extent and interstitial distribution of disease. Soft tissue infiltration and adenopathy are also occasionally seen. Received: 15 January 1999/Accepted: 10 March 1999     

Urinary excretion of orally ingested gastrografin on CT

Renal excretion of orally ingested gastrografin has rarely been reported on computed tomography (CT). We studied the unenhanced scans of 82 patients with bowel disorders or perforation to assess the prevalence of urinary contrast material (CM) in various bowel diseases. We also assessed the clinical significance of this sign. In addition, we reviewed the unenhanced CT scans of 100 randomly selected patients without bowel diseases as a control group. Twenty-nine of the 58 patients with bowel diseases, six of nine with free perforation, and one of 15 with covered perforation had CM in the urinary tract. None of the 100 without bowel disease showed urinary CM. Statistical analysis was done by using the Fisher's exact test. The prevalence of urinary CM was highest in inflammatory bowel disease, radiation enteritis, and free perforation (p < 0.0001). This study shows that the CT finding of orally ingested gastrografin in the urinary tract differentiates patients with bowel disease from those without. Received: 2/13/97/Accepted: 3/19/97     

Crohn disease of the small bowel: MR enteroclysis versus conventional enteroclysis

Enteroclysis has been suggested as the technique of choice for the evaluation of Crohn disease of the small intestine. Adequate distention of the entire small bowel with barium suspension allows the radiologic demonstration of mucosal abnormalities and provides functional information by defining distensibility or fixation of the small bowel loops. The principal disadvantage of conventional enteroclysis is the limited indirect information on the state of the bowel wall and extramural extension of Crohn disease, and its effectiveness may be hindered owing to overlapping bowel loops. Moreover, the radiation dose administered to patients, mostly at a young age, should be considered. Magnetic resonance (MR) enteroclysis is an emerging technique for small bowel imaging and was introduced to overcome the limitations of conventional enteroclysis and MR cross-sectional imaging by combining the advantages of both into one technique. MR enteroclysis has the potential to change how the small bowel is assessed because of the functional information, soft tissue contrast, direct multiplanar imaging capabilities, and lack of ionizing radiation.     

Late-phase enhancement of the upstream portion of pancreatic adenocarcinoma on dual-phase helical CT

Background: Late-phase enhancement of pancreatic parenchyma upstream (tail side) of pancreatic adenocarcinoma is found frequently on dual-phase helical computed tomography (CT). We measured the frequency of late-phase enhancement of the upstream portion of pancreatic adenocarcinoma and normal pancreatic parenchyma using dual-phase helical CT. Methods: Twenty-one patients with pancreatic adenocarcinoma and nontumorous pancreas upstream of tumors were compared with 100 control patients without pancreatic disease. Early and late scans started at 25 and 75 s, respectively, after intravenous injection of contrast material. The attenuation values of normal and nontumorous pancreas upstream of tumors were assessed in three phases: precontrast, early, and late enhanced. Enhancement ratio (ER) was calculated as ER = (late phase − precontrast)/(early phase − precontrast). Results: Late-phase enhancements (ER > 1.0) were seen in 86% of upstream pancreas and 10% of normal pancreas. The mean ER of upstream pancreas was significantly higher than that of normal pancreas (p < 0.01). Conclusion: Late-phase enhancement of the pancreas upstream of the tumor is frequently observed in patients with pancreatic adenocarcinoma. Late-phase enhancement and histology showed a correlation for chronic obstructing pancreatitis in five patients. Received: 30 October 2000/Revision accepted: 7 February 2001     

Evaluation of pancreatic carcinoma with FDG PET

Background: To assess the diagnostic usefulness and clinical impact of positron emission tomography with [F-18]fluorodeoxyglucose (FDG PET) on the management of patients with known or suspected pancreatic carcinoma. Methods: Attenuation-corrected FDG PET was performed in 20 patients (12 male, eight female) with pancreatic carcinoma at the time of initial diagnosis (n = 7), for tumor surveillance after Whipple surgery (n = 11), and for reevaluation after chemoradiation therapy (n = 2). Visual analysis of PET images were correlated with the results of abdominal computed tomography (CT) and carbohydrate antigen (CA) 19-9 serum tumor marker level that were obtained within 1 month of the PET study. Diagnostic validation was by histology in nine patients and by clinical or radiologic follow-up (5–48 months) in 11 patients. Changes in therapeutic management that were prompted by PET were tabulated. Results: PET was concordant with the findings of abdominal CT in 14 patients (13 true positive, 1 true negative). PET detected clinically unsuspected lung lesions, confirmed subsequently by a chest CT, in one of these 14 patients. PET was discordant with CT in six patients. PET detected tumor recurrence in three patients in this group (15% of total) with nondiagnostic CT findings and elevated CA 19-9 serology. In two of these three patients, chemotherapy with gemcitabine was initiated based on PET localization of disease. Tumor was confirmed in the remaining one of the three patients at autopsy shortly after the PET study. FDG localization in a displaced loop of bowel resulted in an apparent false-positive hepatic lesion in one of six patients in the discordant group. PET underestimated the extent of metastatic disease in the remaining two of six patients due to hyperglycemia. Conclusion: In patients with suspected pancreatic carcinoma at the time of initial presentation, PET is complementary to abdominal CT and allows detection of unsuspected distant metastases. In patients with suspected recurrent pancreatic carcinoma, based on elevated or rising CA 19-9 serology, PET can localize the disease when abdominal CT is nondiagnostic as a result of posttherapy anatomic alteration. Imaging evaluation with PET may impact the clinical management of patients with pancreatic carcinoma. Received: 1 August 2000/Accepted: 20 September 2000     

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     

Role of duplex color Doppler ultrasound, computed tomography, and MR angiography in the diagnosis of septic puerperal ovarian vein thrombosis

Background: Septic puerperal ovarian vein thrombosis (SPOVT) is one of the underlying etiologies of puerperal fever. A correct diagnosis of this condition is important because adequate treatment requires additional administration of anticoagulants. The purpose of this study was to evaluate the role of duplex color Doppler ultrasound (CDUS), computed tomography (CT), and magnetic resonance angiography (MRA) in the detection of SPOVT. Methods: Twenty-six patients with puerperal fever suspected to be due to SPOVT and unresponsive to broad antibiotic treatment for at least 48 h were included in a prospective study using CDUS, CT, and MR imaging including MRA. Examinations were analyzed and then correlated to a standard of reference gathered from surgical and clinical follow-up data and from results of imaging. Results: SPOVT was present in nine patients (right side n = 8, bilateral n = 1). CDUS was inconclusive due to gaseous distention of the bowel or obesity in 13 of 26 cases. After counting inconclusive findings as wrong results for statistical purposes, sensitivity, specificity, and accuracy for CDUS were 55.6%, 41.2%, and 46.2%, respectively. CT had a sensitivity of 77.8% with a specificity of 62.5%; accuracy was 68.0%. MRA rendered conclusive results in all evaluated patients, resulting in a sensitivity and specificity of 100%. Conclusion: MRA is recommended in all patients with inconclusive CDUS findings and persistent suspicion for SPOVT. CT has the advantage of more rapid access and lower cost and thus will probably remain a sufficiently accurate alternative. Received 29 July 1997/Accepted 24 September 1997     

Pericaval fat collection mimicking an intracaval lesion on CT in patients with chronic liver disease

Background: Localized fat collections, which mimic fat-containing lesions of the inferior vena cava (IVC) on computed tomographic (CT) images, have been reported as rare incidental findings. Our goal was to evaluate the association of this CT finding with chronic liver disease. Methods: Sixty-one patients with chronic liver disease were prospectively studied with contrast-enhanced abdominal CT. The prevalence, attenuation, location, shape, and size of the pericaval fat collections were assessed. Multidirectional reformatted CT images were obtained from helical CT data to identify origins of the pericaval fat collections. Sixty-one patients without chronic liver disease were studied as control subjects. Results: Pericaval fat collections were seen on abdominal CT in 16 (26.2%) of the 61 patients. On the reformatted images, the fat collections were contiguous to the fat tissue around the subdiaphragmatic esophagus in all 16 patients. The fat collections were located at the posterior aspect of the IVC in 12 patients. In the control group, pericaval fat collection mimicking an intracaval lesion was not seen. Conclusion: In patients with chronic liver disease, pericaval fat collections are not rare CT findings and their characteristic location is considered to be posterior to the IVC. It is important not to misinterpret such CT findings as abnormalities of the IVC, such as thrombus or tumors. Received: 18 October 2000/Accepted: 15 November 2000     

Perforations of the rectosigmoid colon induced by cleansing enema: CT findings in 14 patients

Background: We report the computed tomographic (CT) features of colorectal perforations caused by cleansing enema. Methods: We reviewed the medical records and CT studies of all patients with colorectal perforations caused by a cleansing enema. Results: Fourteen patients (10 men, four women; average age = 80 years) were included in the study. The most common presenting symptoms were severe abdominal pain and fever. CT was performed within 48 h after the event in most patients. Extraluminal air in the perirectal fat was the most frequent finding on CT and was present in all patients. Additional findings were extraperitoneal (n = 9), intraperitoneal (n = 3) and /or subcutaneous (n = 3) air, free fluid (n = 9), extraluminal feces (n = 8), and focal bowel wall thickening (n = 4). No leak of contrast from the rectum was observed in any patient including the one patient in whom contrast was administered rectally. Ten patients were treated by surgery; five recovered and the other five died. The other four patients were treated conservatively and all four died. Conclusion: The diagnosis of colorectal perforation can be made on CT. Because the diagnosis is not always suspected by the clinician, the radiologist may be the first to suggest it. Therefore, the radiologist should be familiar with the CT features of a potentially lethal, rectally induced perforation. Received: 19 April 2001/Revision accepted: 4 July 2001     

CT differentiation between necrotic and nonnecrotic small bowel in closed loop and strangulating obstruction

Background: The purpose of this study was to evaluate computed tomographic (CT) findings for predicting the presence of intestinal necrosis in patients with closed loop and strangulating obstruction of the small bowel. Methods: Twenty-five patients with surgically confirmed closed loop and strangulating obstruction were divided into two groups with (n= 16) and without (n= 9) intestinal necrosis. By using univariate and multivariate statistical procedures, we evaluated the differences in CT findings between the two groups on the basis of the following six findings: bowel dilatation of strangulated loops (bowel dilatation), wall thickening of strangulated intestines (wall thickening), ascites, vascular dilatation of affected mesenteries (vascular dilatation), elevation of mesenteric attenuation (mesenteric attenuation), and radial distribution of the mesenteric vessels (radial distribution). Results: Of the six findings, ascites, vascular dilatation, mesenteric attenuation, and radial distribution provided significant discriminating findings between the two groups on univariate analysis. On multivariate analysis, mesenteric attenuation was the most important discriminative factor, followed by radial distribution and ascites. Using these three parameters, the CT was correlated with the surgical findings in 15 of the 16 patients in the necrosis group (sensitivity = 93.8%) and in eight of the nine patients in the nonnecrosis group (specificity = 88.9%). The overall accuracy was 92.0%. Conclusions: Mesenteric attenuation, radial distribution, and ascites, depicted on CT differentiate well between necrosis and nonnecrosis of the small bowelin patients with closed loop and strangulating obstruction. Received 5 December 1997/Accepted: 14 January 1998     

Helical CT anatomy of pancreatic arteries

Background: To assess the frequency of visualization of pancreatic arteries in the arterial phase of helical computed tomography (CT). Methods: The visibility of pancreatic and peripancreatic arteries in helical CT images was evaluated in 20 consecutive patients who had no evidence of pancreatic disease. CT examinations were performed by using a continuously rotating CT scanner and intravenous injection of contrast media. The scans were taken 35 s after the start of injection and with a table speed of 3 mm/s. Images were reconstructed in 3-mm section increments. Results: Frequently visualized arteries were the gastroduodenal, anterior and posterior superior pancreaticoduodenal, and right gastroepiploic arteries. Infrequently visualized arteries were the dorsal pancreatic, pancreatica magna, caudal pancreatic, transverse pancreatic, and common, anterior, and posterior inferior pancreaticoduodenal arteries. Conclusion: Helical CT enabled us to recognize small pancreatic arteries, and the evaluation of these arteries should be considered in the staging of pancreatic carcinoma. Received: 6 June 1995/Accepted: 22 July 1995     

Altered flow dynamics of intravascular contrast material to the liver in superior vena cava syndrome: CT findings

Background: To evaluate the findings of altered flow dynamics in the livers of patients with obstruction of superior vena cava (SVC) on helical computed tomography (CT). Methods: In six patients (age range = 28–80 years) with SVC obstruction, CT findings were retrospectively reviewed to identify the abnormal enhancement patterns of the liver and the relation with the extrahepatic collateral vessels and hepatic vessels. Results: Abnormal hepatic enhancement was observed in the following four (A–D) portions: (A) anterior portion of segment IV (n = 5), (B) subdiaphragmatic portion of the liver (n = 4), (C) posterior portion of the right lobe (bare area; n = 1), and (D) lateral segment of the left lobe (n = 2). Two major collateral pathways to the liver were demonstrated as follows: A and D → from the umbilical vein to the left portal vein, and B and C → from the subcapsular vein to the bare area of the liver or to the hepatic veins. On helical CT, these collateral pathways were also clearly visualized. Conclusion: When these abnormal enhancements of the liver on CT are recognized within the liver, these findings indicate diversion of contrast material into collateral pathways to the liver with SVC obstruction. Received: 31 March 1999/Revision accepted: 25 June 1999     

Three-dimensional spiral CT cholangiography with minimum intensity projection in patients with suspected obstructive biliary disease: comparison with percutaneous transhepatic cholangiography

Background: To evaluate the diagnostic potential of spiral computed tomographic (CT) cholangiography with minimum intensity projection (minIP) in the diagnosis of patients with suspected biliary obstruction. Methods: Nine consecutive patients with obstructive biliary disease were enrolled in this study. Spiral CT data (3-mm slice thickness, pitch 1∼2:1) obtained 65 s after the start of contrast medium injection (150 mL Ultravist 370, 3 mL/s) were reconstructed at 1-mm intervals. Three-dimensional (3D) CT cholangiography with minIP (3D CTC) was generated with a Siemens software package. The quality of 3D CTC in its ability to demonstrate the anatomic detail, the level of obstruction, and the presence or absence of isolated hepatic segments was evaluated using percutaneous transhepatic cholangiography as a gold standard. Results: In all patients, 3D CTC demonstrated dilated intrahepatic ducts up to tertiary branches. 3D CTC correctly diagnosed the level of biliary obstruction and demonstrated isolated segments in all patients. In determining the cause of biliary obstruction, one patient with hilar cholangiocarcinoma was misdiagnosed as having biliary invasion by hepatocellular carcinoma. Conclusion: 3D CTC with minIP can determine the level and cause of biliary obstruction. 3D CTC can be obtained from regular thin-section helical CT data and may be a strong competitor against diagnostic magnetic resonance cholangiography because of its superior resolution and information on adjacent soft tissues and the duct itself. Received: 7 July 2000/Accepted: 23 August 2000