Gallbladder Metastasis of Renal Cell Carcinoma: A Case Report

The gallbladder (GB) is a rare site of renal cell carcinoma (RCC) metastasis. To the best of our knowledge, only a few reports of CT findings of GB metastasis exist in the literature. Herein, we report a case of histologically proven GB metastasis of RCC in a 55-year-old male who underwent CT for an intraluminal polypoid mass simulating a primary GB lesion.

Gallbladder Metastasis of Renal Cell Carcinoma: A Case Report

The gallbladder (GB) is a rare site of renal cell carcinoma (RCC) metastasis. To the best of our knowledge, only a few reports of CT findings of GB metastasis exist in the literature. Herein, we report a case of histologically proven GB metastasis of RCC in a 55-year-old male who underwent CT for an intraluminal polypoid mass simulating a primary GB lesion.

Transpedal lymphatic embolization for lymphorrhea at the graft harvest site after coronary artery bypass grafting / 영남의대학술지

Lymphorrhea is a rare but potentially severe complication that occurs after various surgical procedures. Untreated lymphorrhea may lead to wound dehiscence, infection, and prolonged hospital stay. Currently, there is no standard effective treatment. Early management usually includes leg elevation, drainage, and pressure dressing. However, these methods are associated with prolonged recovery and high recurrence rates. We report a case of lymphorrhea from a calf wound after endoscopic great saphenous vein (GSV) harvesting for coronary artery bypass grafting (CABG). The patient presented with intractable oozing from the postoperative wound on the right calf. Lymphorrhea perGsisted for 6 weeks despite negative-pressure wound therapy with a long-acting somatostatin. We performed unilateral pedal lymphangiography that confirmed wound lymphorrhea, followed by glue embolization. No recurrence was observed after 8 months of follow-up. This case report demonstrates the successful use of lymphangiography with glue embolization in the control of lymphorrhea after GSV harvesting for CABG.

A Case of Pancreatic Pseudocyst with an Atypical Multilocular Appearance on Endoscopic Ultrasound

Pancreatic pseudocysts are focal fluid collections that develop as a result of inflammatory diseases of the pancreas. They are managed conservatively or with a drainage procedure. Their radiological appearance can mimic cystic neoplasms of the pancreas. Pancreatic cystic neoplasms include various neoplasms with a wide range of malignant potential. Here, we report a patient with a pancreatic pseudocyst that presented with macrocystic attributes on endoscopic ultrasound.

Detection of the Transition Zone and Adhesions in the Diagnosis of Adhesive Small-bowel Obstruction: the Added Value of Ultrasonography (US) in Comparison with Only CT Imaging

PURPOSE: We aimed to assess retrospectively the benefit of the use of ultrasonography (US) in comparison with the use of only CT imaging for the detection of the transition zone and adhesions to determine a diagnosis of adhesive small-bowel obstruction (SBO). MATERIALS AND METHODS: Thirty-five patients underwent an additional US examination after CT imaging to determine a diagnosis of SBO. All of the patients were surgically confirmed as having adhesive SBO. The CT images were interpreted for the location of the transition zone, the location and shape of adhesions and for other SBO findings. All of the additional US scans were performed with reference to the CT findings. The standard of reference for the diagnosis was the surgical findings. The diagnostic accuracy and mean confidence score of the transition zone location and the detection rate of adhesions were evaluated for both CT imaging alone and for CT imaging with additional US. RESULTS: The diagnostic accuracy to locate the transition zone was significantly increased with the use of additional US with CT imaging (94.6%, 33/35) as compared to 65.7% (23/35) with the use of only CT imaging (p = 0.01). The mean confidence score was significantly increased (by 0.95) with the use of an additional US examination (p < 0.01). The detection rate for adhesions was 20% (7/35) with the use of only CT imaging and the detection rate was 68.6% (24/35) with the use of an additional US examination. CONCLUSION: The use of a US examination in addition to CT imaging can increase the accuracy and confidence to locate the transition zone and can increase the rate to detect adhesions in patients with adhesive SBO. An additional US examination may be especially helpful when the CT findings are equivocal.

An intraperitoneal tuberculous abscess: Computed tomography (CT) findings and clinical course / 대한내과학회지

BACKGROUND/AIMS: Intraperitoneal tuberculous abscesses develop infrequently. Because of overlapping features it is difficult to differentiate a tuberculous abscess from carcinomatosis peritonei. The aim of this study was to define the computed tomography (CT) findings and clinical course of the intraperitoneal tuberculous abscess. METHODS: The study included 11 patients (3 males, 8 females, mean age 34.8 years) with a pathologically proven intraperitoneal tuberculous abscess. We analyzed the CT findings and reviewed the medical records retrospectively. RESULTS: Sixteen abscesses were found in 11 patients. The locations of the abscesses were in the right subphrenic space (n=1), right perihepatic space (n=4), left perihepatic space (n=4), left subphrenic space (n=2), perisplenic space (n=3), right lower abdominal space (n=1), and left lower abdominal space (n=1). Five patients were proven to have abdominal tuberculosis while six patients had paradoxical responses to antituberculosis therapy for tuberculous peritonitis. The abscess lesions presented on the CT scan as thin walled cystic enhancing lesions without calcification (n=16), a septated mass (n=12), with enlargement of lymph nodes (n=2), and peritoneal and omental haziness (n=3). The mean duration from commencement of treatment to onset of a paradoxical response was 88 days. All patients had antituberculosis therapy for 6 to 12 months and five patients underwent surgery. The mean follow-up was 15 months. CONCLUSIONS: The intraperitoneal tuberculous abscess appeared as an ovoid cystic lesion with a slightly enhanced thin wall in the upper abdomen, in the perihepatic space on the CT scan; such as lesion can be the primary lesion of abdominal tuberculosis or associated with the paradoxical response of tuberculous peritonitis.

Localized Intrahepatic Bile Duct Dilatation without a Visible Mass or Stone as depicted on CT Images: Findings of Malignancy Prediction

PURPOSE: This study was performed to evaluate factors that can predict the presence of a malignancy for localized intrahepatic bile duct dilatation without a visible mass or stone as depicted on CT images. MATERIALS AND METHODS: A total of 29 patients (male: 16, female: 13) who had localized intrahepatic bile duct dilatation without a visible mass, stone or injury as depicted on CT images were included in the study. A history of extrahepatic malignancy and biliary stone disease, tumor marker levels, CT findings of the intrahepatic bile duct and associated findings were reviewed. The findings were analyzed between two groups (patients with a malignancy and patients with benign disease) on follow-up. RESULTS: In 29 patients, 11 patients had malignant lesions (four metastases and seven cholangiocarcinomas). The history of an extrahepatic malignancy and the shape of an intrahepatic duct obstruction or stenosis as seen on CT were significantly correlated with the results between the benign and malignant group of patients. The follow-up results of the malignant group of patients indicated that for six patients who had developed a new mass, one patient each showed aggravation of ductal dilatation and thickening of the ductal wall. CONCLUSION: When a patient with localized intrahepatic bile duct dilatation without a definite cause has a history of an extrahepatic malignancy or shows abrupt tapering or irregular narrowing on CT images, short-term follow-up should be performed. The patient should be investigated carefully for mass formation or a change of the dilated bile duct due to a possibility of malignant ductal dilatation.

Current Status of Clinical Image Evaluation of Mammograms: Preliminary Report

PURPOSE: To survey the current overall quality of mammograms and to improve Korean standards in comparison to the American College of Radiology (ACR) standards for clinical image evaluations. MATERIALS AND METHODS: A total of 104 mammograms, collected from 63 hospitals and clinics, were examined following the revised new Korean standards and ACR standards for clinical image evaluation. The pass and failure rates of the mammogram were evaluated according to each of the standards compared. The pass threshold for the Korean standards was analyzed using the ROC (receiver operating characteristic) curve in association with the ACR standards. The categories of the Korean standards were evaluated in association with failure of the ACR standards. RESULTS: Among the 104 mammograms, 99.0% passed the Korean standards, whereas 86.5% passed the ACR standards. A score of 75.5 was the pass threshold for the Korean standards. Moreover, the Korean standards categories associated with the failure of ACR standards included positioning, compression, and contrast/exposure (p < 0.05). CONCLUSION: The pass rate of the image evaluation for each mammogram following the Korean standards was 99%, compared to 86.5% for the ACR standards. Hence, the Korean standards were not as stringent. Consequently, stricter regulations are suggested for improvement in the quality of mammograms.

Measurement of the Mucosal Surface Distance in the Early Gastric Cancer Using CT Gastrography

PURPOSE: Recently, the incidence of early gastric cancer (EGC) patients is rapidly increased in Korea. However, they're often not perceptible by surgical palpation or inspection. The aim of this study is 1) to develope a software that can locate the tumor and measure the mucosal distance from an anatomic landmark to the tumor using CT gastrography and 2) to compare the distance measured by the developed software with the distance measured by the pathologic findings. MATERIALS AND METHODS: Between January 2004 and September 2005, sixty patients (male=45, female=15, mean 57.8 years old) estimated for EGC with preoperative CT scans and undergone gastrectomies in Kyungpook National University Hospital were enrolled in this study. Preoperative CT scans were performed after insufflations of room air via 5 Fr NG tube. The scans included the following parameters: (slice thickness/reconstruction interval: 0.625 mm, kVp: 120, mAs: 200). 3D volume rendering and measurement of the surface distance from the pylorus to the EGC were performed using the developed software. RESULTS: The average difference between the lesion to pylorus distances measured from pathologic specimens and CT gastrography was 5.3+/-2.9 mm (range 0~23 mm). The lesion to pylorus distance measured from CT gastrography was well correlated with that measured from the pathologic specimens (r=0.9843, P<0.001). CONCLUSION: These results suggest that the surface distance from an anatomic landmark to the EGC can be measured accurately by CT gastrography. This technique could be used for preoperative localization of early gastric carcinomas to determine the optimal extent of surgical resection.

Ultrasound-guided Percutaneous Cholecysto-Cholangiography for the Exclusion of Biliary Atresia in Infants

PURPOSE: The aim of this study is to determine the feasibility and effectiveness of performing an ultrasound-guided percutaneous cholecysto-cholangiogram (PCC) for excluding biliary atresia as the cause of neonatal jaundice. MATERIALS AND METHODS: Between Oct. 2003 and Feb. 2005, six ultrasound-guided PCC procedures were performed to five jaundiced infants (4 females and 1 male; mean age: 60 days old) for whom possibility of biliary atresia could not be ruled out by the DISIDA scan as the cause of their neonatal jaundice. Gallbladder puncture was performed under ultrasound guidance with a 23-gauge needle. Contrast material injection during fluoroscopic examination was performed after dilatation of the gallbladder lumen with normal saline under ultrasound guidance. The criteria used for excluding biliary atresia were complete visualization of the extrahepatic biliary trees and/or contrast excretion into the duodenum. The complications and final diagnosis was assessed according to the clinical and laboratory findings. RESULTS: The procedures were successful in all the patients without any complication. Biliary atresia could be ruled out in all the patients. The final diagnosis was neonatal cytomegalovirus hepatitis in two patients, total parenteral nutrition-associated cholestasis in two patients, and combined cytomegalovirus hepatitis and total parenteral nutrition-associated cholestasis in one patient. CONCLUSION: Ultrasound-guided PCC is a feasible and effective method for the early definitive exclusion of biliary atresia as the cause of neonatal jaundice. By the technique of injecting normal saline before contrast injection, PCC can be done even in a totally collapsed or very small gallbladder.

The Value of Doppler-ultrasonography and Laboratory Tests as Non-invasive Predictors of the Presence of Esophageal Varices in Patients with Chronic Liver Disease / 대한소화기학회지

BACKGROUND/AIMS: Upper gastrointestinal endoscopy is usually recommended for the evaluation of esophageal varices in patients with liver cirrhosis. However, the prevalence of varices is extremely variable. We performed this study to determine the predictive values for esophageal varices and to select eligible patients for screening endoscopy. METHODS: Fifty-two patients were enrolled in this study. Laboratory tests including liver biochemistry and complete blood count along with ultrasonography with Doppler measurements and endoscopy were performed. RESULTS: Esophageal varices were present in 25 patients (48%). Variables associated with the presence of esophageal varices on univariate analysis were serum albumin, total bilirubin, prothrombin time and platelet count (p<0.05). Significant variables in ultrasonography with Doppler measurement were diameter of spleen (13.04+/-2.1 cm vs. 10.39+/-1.6 cm, p<0.001), peak velocity of portal vein (30.2+/-7.5 cm/sec vs. 36.1+/-8.0 cm/sec, p<0.01) and portal vein diameter (1.26+/-0.28 cm vs. 1.13+/-0.18 cm, p<0.05). On multivariate analysis, independent variables were platelet count (odds ratio (OR) 0.922; 95% confidence interval (CI), 0.86-0.99), diameter of spleen (OR 5.4; 95% CI, 1.63-17.88) and platelet count/spleen diameter ratio (OR 1.007; 95% CI, 1.01-1.02). The optimal critical value for the diameter of spleen was 11 cm. The sensitivity and specificity with this value were 84% and 63%, respectively. CONCLUSIONS: Doppler measurement was not helpful in distinguishing the presence of varices. However, clinical tests including biochemistry and ultrasonography would be useful in selecting eligible patients for screening endoscopy. Endoscopic screening for esophageal varices is recommended in cirrhotic patients with splenomegaly.

Feasibility of Ultrasonography and MR Arthrography during Evaluation of Rotator Cuff Injury

PURPOSE: To evaluate the feasibility of MR arthrography and ultrasonography in evaluating shoulder pain. MATERIALS AND METHODS: The subject group consisted of all patients who visited our institute complaining of shoulder pain or instability from June 2002 to December 2004. There were a total of 92 patients with a mean age of 48. On the basis of arthroscopic results, the sensitivity, specificity, and accuracy of ultrasonography and MR arthrography were evaluated by comparing them with each other. RESULTS: In the diagnosis of supraspinatus tendon tears, ultrasonography had sensitivity and specificity of 100% and 64%, respectively, whereas MR arthrography had sensitivity and specificity of 80% and 94%, respectively. Ultrasonography also had high sensitivity and specificity in the diagnosis of subscapularis tendon tears (100% and 90%). MR arthrography was appropriate for identifying glenoid labral abnormalities (sensitivity, 95% and specificity, 61%). Similar results from ultrasonography and MR arthrography were obtained in the diagnosis of subscapular tendon tears or full-thickness tears of the rotator cuff tendons (kappa value, 0.644 and 0.911). CONCLUSION: While evaluating rotator cuff abnormalities, ultrasonography was appropriate for screening, whereas MR arthrography was useful to confirm the results of the ultrasonography.

Preoperative Detection of Hepatic Metastases from the colorectal Cancers: Comparison of Dual-phase CT scan, Mn-DPDP enhanced MRI, and combination of CT and MRI

PURPOSE: To determine the usefulness of additional Mn-DPDP MRI for preoperative evaluation of the patients with colorectal cancers by comparison of dual-phase CT scan, Mn-DPDP enhanced MRI and combination of CT and MRI. MATERIALS AND METHODS: Fifty-three colorectal cancer patients with 92 metastatic nodules underwent dualphase (arterial and portal) helical CT scan and Mn-DPDP MRI prior to surgery. The indication of MRI was presence or suspected of having metastatic lesions at CT scan and/or increased serum carcinoembryonic antigen (CEA) levels (10 ng/mL or more). The diagnosis was established by the combination of findings at surgery, intraoperative ultrasonography, and histopathologic examination. Two radiologists interpreted CT, MRI, and combination of CT-MRI at discrete sessions and evaluated each lesion for location, size, and intrinsic characteristics. The lesions were divided into three groups according to their diameter; 1cm 2 cm. Diagnostic accuracy was evaluated using the alternative-free response receiver operating characteristic method. Detection and false positive rate were also evaluated. RESULTS: In the lesions smaller than 1 cm, detection rate of combined CT-MRI was superior to CT or MRI alone (82%, p = 0.036). The mean accuracy (Az values) of combined CT and MRI was significantly higher than that of CT in the lesions smaller than 2 cm (1 cm <, p=0.034; 1-2 cm, p=0.045). However, there was no significant difference between MRI and combined CT-MRI. The false positive rate of CT was higher than those of combined CT-MR in the lesions smaller than 1 cm (28 %, p=0.023). CONCLUSION: Additional MRI using Mn-DPDP besides routine CT scan was helpful in differentiating the hepatic lesions (< 2 cm) and could improve detection of the small hepatic metastases (< 1 cm) from colorectal carcinoma.

A Case of Acute Adrenal Insufficiency with Bilateral Adrenal Hemorrhagic Infarction due to Ebstein-Barr Virus Infection in a Patient with Asymptomatic Chronic Adrenal Insufficiency / 대한내분비학회지

Acute adrenal insufficiency may result from adrenal crisis, hemorrhagic destruction, or the rapid withdrawal of steroids from patient with chronic steroid medication, congenital adrenal hyperplasia or those on other drugs. Acute hemorrhagic destruction of both adrenal glands can occur due to infection, trauma, anticoagulant therapy, antiphospholipid syndrome or a coagulation disorder. However, there have been no reports on acute hemorrhagic adrenal insufficiency due to the Ebstein-Barr virus (EBV). Herein, a case of acute adrenal insufficiency, with bilateral adrenal hemorrhagic infarction, is reported in a patient with asymptomatic chronic adrenal insufficiency. A 42-year-old man presented with general weakness, weight loss and hyperpigmentation of several months duration. He suffered from a sore throat, general myalgia and a headache on admission. The laboratory findings were lymphocytosis, positive EBV IgM antibody, low cortisol level and a high level of adrenocorticotropic hormone (ACTH). Adrenocortical autoantibody and PCR for Mycobacterium tuberculosis showed negative findings. The serologic findings for CMV and HIV were negative. Fine needle aspiration of the adrenal gland revealed a hemorrhagic infarction and positive staining for the anti-EBV antibody. Acute adrenal insufficiency was then diagnosed with a bilateral adrenal hemorrhagic infarction due to the EBV infection in the patient, also with asymptomatic chronic adrenal insufficiency. This is the first case of acute adrenal insufficiency with bilateral hemorrhagic infarction, due to an EBV infection

Quantitative Evaluation of Liver Function with MRI Using Gd-EOB-DTPA

OBJECTIVE: Gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) is a newly developed MR contrast agent. After intravenous injection, Gd-EOB-DTPA is gradually taken up by the hepatocytes and eventually excreted via the biliary pathway without any change to its chemical structure. Because of these characteristics, it can be used as a tracer for quantitative liver function testing. The purpose of this study is to develop a noninvasive method of quantitation of the hepatic function using Gd-EOB-DTPA through the deconvolution analysis. MATERIALS AND METHODS: Adult New Zealand white rabbits (n = 10, average body weight = 3.5 kg) were used in the present study. Hepatic injury was induced to by the intragastric administration of carbon tetrachloride (CCl4) three times a week for three weeks. Liver enzyme (aspartate aminotransferase, AST; alanine aminotransferase, ALT) levels and the plasma indocyanine green (ICG) retention rate 15 minutes after an intravenous injection of ICG (ICG R15), was checked before and after the three-week administration of CCl4. At the end of experimental period, an observer "blinded" to the treatment given the rabbits performed the histological examination. MRI studies were performed before and after the three-week administration of CCl4 on a 1.5 T scanner using a human extremity coil. After intravenous bolus injection of Gd-EOB-DTPA (0.3 mL of Gd-EOB-DTPA freshly prepared in 2.7 mL of normal saline) through the ear vein, the 250 axial single level dynamic MR images were obtained using a fast low angle shot (FLASH, TR/TE = 11/4.2 msec, flip angle = 15, acquisition time 1 second, slice thickness = 5 mm, matrix = 128x128, field of view = 120 mm) sequence with 1.5 sec time intervals. The time-intensity curves were obtained at the abdominal aorta and the liver parenchyma that was devoid of blood vessels. Deconvolution analysis of the aortic (input function) and hepatic parenchymal (output function) time-intensity curves was performed with a modified Fourier transform technique to calculate the hepatic extraction fraction (HEF). The presence and type of hepatic injury were determined by the histopathologic examination and statistical analysis of the changes of the hepatic enzyme levels, the ICG R15 and Gd-EOB-DTPA HEF values between the time before and after CCl4 administration with Wicoxon signed rank test. Correlation between the Gd-EOB-DTPA HEF and the change of the ICG R15 were analyzed with Pearson's correlation coefficient. RESULTS: Histopathologic examination showed findings that were compatible with hepatic fibrosis caused by chronic liver injury. The initial blood biochemical studies before the administration of carbon tetrachloride showed that the mean AST and ALT levels were 39.8+/-5.2 IU/L and 59.1+/-11.7 IU/L, respectively. The AST and ALT levels increased to 138.4+/-50.5 IU and 172.0+/-71.6 IU/L, respectively, after the three week administration of CCl4. The ALT and AST levels were significantly increased after the three weeks of CCl4 administration (p=0.018). The ICG R15 values were 4.47+/-2.08% and 19.43+/-3.98% before and after three-week administration of CCl4, respectively. The ICG R15 values were significantly increased after hepatic injury (p=0.018). After normalizing the HEF as 100% in each rabbit before CCl4 administration, the deconvoluted curve after CCl4 administration revealed less hepatocyte extraction efficiency with a mean value of 77.7+/-3.6. There was a significant correlation between the HEF and changes of the ICG R15 by the Pearson correlation coefficient assessment (correlation coefficient = -0.965, p=0.000). CONCLUSION: The Gd-EOB-DTPA HEF could be calculated from deconvolution analysis of aortic and hepatic parenchymal time-intensity curves obtained by dynamic MRI. The Gd-EOB-DTPA HEF was well correlated with changes of the ICG R15, which is the most common parameter used in the quantitative estimation of the hepatic function. The Gd-EOB-DTPA HEF is a direct, noninvasive technique for the quantitative evaluation of liver function. It could be a promising alternative for the determination of noninvasive hepatic function in those patients with liver disease.

Extragastrointestinal Stromal Tumor Presenting a Large Multilocular Cystic Mass Arising from the Greater Omentum: A Case Report

Extragastrointestinal stromal tumor (EGIST) has been reported to occur only rarely, and the cases of this disease appearing as cystic masses are also known to be very infrequent. Along with a review of the related articles, we report here on a case of EGIST arising from the omentum that was seen as a multiloculated large cystic mass with multiple thick septa and a solid component.

The Effect of Nuclear Overhauser Enhancement in Liver and Heart 31P NMR Spectra Localized by 2D Chemical Shift Technique

PURPOSE: To investigate the signal enhancement ratio by NOE effect on in vivo 31P MRS in human heart muscle and liver. we also evaluated the enhancement ratios of different phosphorus metabolites, which are important in 31P MRS for each organ. MATERIALS AND METHODS: Ten normal subjects (M: F = 8: 2, age range = 24-32 yrs) were included for in vivo 31P MRS measurements on a 1.5 T whole-body MRI/MRS system using 1H-31P dual tuned surface coil. Two-dimensional Chemical Shift Imaging (2D CSI) pulse sequence for 31P MRS was employed in all 31P MRS measurements. First, 31P MRS performed without NOE effect and then the same 2D CSI data acquisitions were repeated with NOE effect. After postprocessing the MRS raw data in the time domain, the signal enhancements in percent were estimated from the major metabolites. RESULTS: The calculated NOE enhancement for liver 31P MRS were: alpha-ATP (7%), beta- ATP (9%), gamma-ATP (17%), Pi (1%), PDE (19%), and PME (31%). Because there is no creatine kinase activity in liver, PCr signal is absent. For cardiac 31P MRS, whole body coil gave better scout images and thus better localization than surface coil. In 31P cardiac multi-voxel spectra, DPG signal increased from left to right according to the amount of blood included. The calculated enhancement for cardiac 31P MRS were: alpha -ATP (12%), beta-ATP (19%), gamma-ATP (30%), PCr (34%), Pi (20%), PDE (51%), and DPG (72%). CONCLUSION: Our results revealed that the NOE effect was more pronounced in heart muscle than in liver with different coupling to 1H spin system and thus different heteronuclear cross-relaxation.

Imaging Findings of Acute Torsion of the Gallbladder: Case Report

Torsion of the gallbladder is a rare and acute abdominal condition. Even with the recent advances in radiologic imaging modalities, it is difficult to make a correct preoperative diagnosis of gallbladder torsion. We recently experienced a case of gallbladder torsion at the body portion in which an accurate preoperative diagnosis could be made on the gray scale and by using color Doppler ultrasonography. We report the imaging and operative findings with particular emphasis on the ultrasonographic "whirlpool sign".

Bezoar Associated with Small Bowel Obstruction: Comparison of CT and US

PURPOSE: To compare the accuracy of computed tomography (CT) and ultrasound (US) in the diagnosis of bezoars in small bowel obstruction. MATERIALS AND METHODS: During a recent eight-year period, 23 patients underwent surgery due to small bowel obstruction caused by bezoars, and 14 who underwent both CT and US were included in this study. The scans obtained were retrospectively reviewed by two radiologists working independently, and the usefulness of each modality in terms of diagnostic capacity, determination of the level of obstruction and detection of additional bezoars was assessed. RESULTS: At surgery, a total of 22 bezoars were removed: 19 from the small intestine and three from the stomach; multiple bezoars were found in five of the 14 patients. The presence of bezoars was demonstrated by CT in all patients, and by US in ten (71%) (p=0.125). The level of obstruction was correctly predicted in 57% of cases at US and in 100% at CT (p=0.03). Overall sensitivity was 55% for US (12/22) and 96% for CT (21/22) (p<0.01). In three patients with associated gastric bezoars, US revealed only one, whereas all were demonstrated by CT. In five with multiple lesions, only five (39%) of 13 were apparent at US, but 12 (92%) were revealed by CT. CONCLUSION: Both US and CT were useful for the diagnosis of small bowel obstruction caused by bezoars. CT however, was more accurate in determining the level of obstruction and in revealing additional bezoars in the small bowel and stomach.

Usefulness of Digital Subtraction Technique in the Contrast-enhanced Multi-phasic Abdominal MR angiography

PURPOSE: To assess the usefulness of digital subtraction contrast-enhanced multi-phase magnetic resonance angiography (MRA) for evaluation of the vessels of the gastrointestinal system. MATERIALS AND METHODS: Twenty-five patients who underwent abdominal MRA for evaluation of the vessels of the gastrointestinal system were included in this study. MRA was performed using a 1.5-T scanner and the 3-D turbo-FLASH sequence. Subtraction images of the arterial and portal venous phases were obtained by subtracting arterial phase images from mask images and portal venous phase images from arterial phase images, respectively. Each set of images was processed using a maximum-intensity projection (MIP) algorithm to produce three-dimensional angiograms. We compared overall image quality and the visibility of normal and abnormal vessels between subtraction and non-subtraction MRA. RESULTS: In terms of subjective image quality, subtraction and non-subtraction MRA was similar both the arterial and portal venous phases (p>0.05). During the arterial phase, subtraction MRA visualized more peripheral branches of the left gastric and superior mesenteric arteries than non-subtraction MRA (p<0.05), and during the portal venous phase, subtraction MRA demonstrated more peripheral branches of the superior mesenteric (p<0.01), splenic (p<0.05) and left portal vein (p<0.05) than non-subtraction MRA. In addition, overall visibility of the arterial and portal venous branches was superior with subtraction MRAs than with non-subtraction MRA. Both of these detected all anomalous arterial branching (n=5) and abnormal (encased or obstructed) portal veins (n=5). Subtraction MRA visualized 17 portal venous collaterals in six patients, whereas non-subtraction MRA visualized only seven collateral veins. CONCLUSION: In contrast-enhanced abdominal MRA, the digital subtraction technique permits visualization of more distal branches of the vessels of both the arterial and portal venous systems without significant degradation of image quality. The technique is particularly useful for the detection of portal venous collaterals in patients with portal hypertension.