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     

Pseudolesion in segment II of the liver observed on CT during arterial portography caused by the aberrant left gastric venous drainage

A rare case with a pseudolesion in segment II of the liver observed on computed tomography (CT) during arterial portography caused by the aberrant left gastric venous drainage is presented. Close observation of the celiac angiography was helpful in recognizing this pseudolesion. Selective catheterization of the left gastric artery and CT during its venous phase confirmed the etiology of the pseudolesion. Received: 11 June 1998/Revision accepted: 9 September 1998     

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     

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     

Gastrointestinal bleeding due to ruptured pseudoaneurysm in patients with pancreatitis

We present the medical imaging results and clinical data of four pancreatitis cases with gastrointestinal bleeding due to rupture of a pseudoaneurysm to determine in which situations a rupture should be suspected. Our observations suggest that the possibility of such a rupture must be kept in mind when encountering not only patients with hematemesis or melena associated with acute severe abdominal symptoms but also patients with severe anemia. Color Doppler sonography and computed tomography are very useful as first-line diagnostic tools and should be performed promptly to prevent a delay in patient management. Received: 25 August 1998/Accepted: 7 October 1998     

Left adrenal vein localization by 3D real-time volume-rendering CTA before laparoscopic nephrectomy in living renal donors

Background: We investigated whether the left adrenal vein could be consistently localized on three-dimensional (3D) real-time volume-rendering computed tomographic angiographic (CTA) mapping in a group of living renal donors before laparoscopic nephrectomy. Methods: Sixty-six consecutive potential renal donors were referred for CTA vascular mapping before laparoscopic donor nephrectomy. Thirty-three patients were examined on a single-detector helical CT scanner and the other 33 were examined on a multidetector unit. In each patient, arterial phase and venous phase volumetric data sets were acquired after the intravenous injection of 150 cc of non-ionic contrast material. Three radiologists reviewed the data sets at a free-standing workstation after the application of 3D volume-rendering software and reached a concensus on whether the left adrenal vein was visualized and, when seen, its position relative to the abdominal aorta. Results: The left adrenal vein was found in 92.5% of the 66 donors (91% in the single-detector group and 94% in the multidetector group). The junction of the left adrenal vein and left renal vein averaged 5.2 mm (range = 0–13 mm) from the left lateral wall of the abdominal aorta. Conclusion: Three-dimensional real-time volume-rendering CTA with single-detector and multidetector scanners permits consistent localization of the left adrenal vein in more than 90 % of prospective living renal donors. Received: 7 September 2000/Accepted: 29 November 2000     

Per-rectal contrast material for abdominal CT: usefulness of administration with an automatic injector

Adequate distention of the gastrointestinal tract is essential for the best quality image in abdominal computed tomography. We introduce a new technique for per-rectal administration of contrast material with the use of an automatic injector. With this technique, more contrast material can be inserted and thus adequately distend the colon, including the proximal colon. Received: 15 September 2000/Revision accepted: 27 December 2000     

Sclerosed hemangioma of the liver

We report the radiologic findings of sclerosed hemangioma (SH), a rare variant of hepatic hemangioma. Dynamic contrast-enhanced computed tomography showed a hypodense mass in the liver with delayed enhancement. T2-weighted magnetic resonance imaging showed the mass as hypointense in relation to cerebrospinal fluid. The final diagnosis of SH was made pathologically. Although SH is rare, understanding its radiologic appearance is important to avoid unnecessary surgery and should be included in the differential diagnoses of hepatic lesion with delayed enhancement. Received: 22 May 2000/Revision accepted: 15 November 2000     

Sonographic diagnosis of intussusceptions in adults

Differentiating bowel intussusception occurring in adults from other bowel diseases represents a diagnostic problem because this condition is not a common finding. Contrast radiography, computed tomography, magnetic resonance imaging, and abdominal ultrasonography are imaging techniques suitable for this diagnosis. Sonography is easy to perform, reproducible, and less invasive than the other techniques. The aim of the present study was to evaluate the diagnostic utility of abdominal sonography in four patients affected by bowel intussusception and to assess the advantages offered by this method. Received: 9 March 1999/Accepted: 7 April 1999     

Gaucher disease of the spleen: CT and MR findings

We present a 26-year-old male patient with Gaucher disease who presented with epigastric pain and a palpable mass in the left abdomen. Ultrasound, abdominal computed tomography, and magnetic resonance imaging showed massive splenomegaly with multiple splenic nodules up to 7 cm in diameter. Splenic nodules should be included in the differential diagnosis of splenic masses. Follow-up is necessary because of the increased incidence of hematologic malignancies in Gaucher disease. Received: 28 September 1999/Accepted: 20 October 1999     

Paraumbilical vein in the cirrhotic patient: imaging with 3D CT angiography

The paraumbilical vein is a common venous collateral in patients with cirrhosis and portal hypertension. This pictorial essay demonstrates the use of computed tomographic angiography with three-dimensional volume rendering techniques to visualize the paraumbilical vein and its relationship to abdominal wall collaterals. The unique anatomy and embryology of this vessel is also discussed. Received: 25 March 1997/Accepted: 30 April 1997     

Computed tomography during arterial portography under temporary balloon occlusion of the hepatic artery: evaluation of pseudolesions caused by arterio-portal venous shunts

Background: Computed tomography during arterial portography (CTAP) under temporary balloon occlusion of the hepatic artery (BOHA-CTAP) was introduced to evaluate pseudolesions caused by portal venous impairments such as arterioportal shunt and tumor thrombus. Methods: BOHA-CTAP was performed in seven patients with hepatocellular carcinoma and correlated with clinical outcomes. For patients with wedge-shaped defects suggestive of pseudolesions, BOHA-CTAP was obtained by a 5-F balloon occlusion catheter into the proper hepatic artery through the second 5-F introducer inserted into the common femoral artery a few centimeters below the first 5-F sheath for CTAP. Results: Eight pseudolesions were determined clinically on follow-up CT, ultrasonography, or magnetic resonance imagings. On BOHA-CTAP, five of the eight pseudolesions were eliminated, and two were diminished in comparision with conventional CTAP. One wedge-shaped defect due to tumor thrombus in the portal vein did not show any change. Conclusion: BOHA-CTAP can reduce pseudolesions caused by portal venous impairments and enable the demarcation of the true tumors. RID=" ID=" <E5>Correspondence to:</E5> J. Koizumi Received: 3 August 1999/Revision accepted: 8 March 2000     

Capsular retraction in hepatic giant hemangioma: CT and MR features

We report two cases of hepatic giant hemangiomas with capsular retraction of the liver adjacent to the tumor on computed tomography and magnetic resonance images. Our cases show that the retraction of the liver capsule adjacent to the tumor is not a finding specific to malignant hepatic tumors but can also be observed in benign hepatic tumors. Received: 16 May 2000/Accepted: 14 June 2000     

Annular pancreas in adults: imaging features in seven patients

BACKGROUND: Annular pancreas is a rare congenital abnormality that may be associated with variable degrees of duodenal obstruction. This diagnosis is often overlooked in adult patients who present with symptoms suggestive of duodenal obstruction. Imaging evaluation aids in establishing the diagnosis. We evaluated the imaging findings in seven adult patients with known annular pancreas. METHODS: Seven adult patients with abdominal symptoms had evaluation with one or more of the following imaging studies: upper gastrointestinal (UGI) series, computed tomography (CT), and endoscopic retrograde cholangiopancreatography (ERCP). All patients underwent subsequent laparotomy as a part of routine care. Surgical and imaging findings were correlated in each patient. RESULTS: UGI series is suitable for demonstrating different degrees of duodenal narrowing at the level of pancreatic annulus. Contrast-enhanced abdominal CT is useful in visualizing directly the complete or partial annular pancreatic tissue. ERCP is particularly useful in visualizing the annulus duct coursing around the duodenum. CONCLUSIONS: Imaging plays a pivotal role in the diagnosis of annular pancreas in adult patients avoiding surgery for confirmation with its associated cost and risks.     

CT of small bowel obstruction in adults

The increasing use of computed tomography in evaluating patients with acute abdominal pain has revolutionized the diagnosis of small bowel obstruction in adults. Computed tomography is incontestably the most useful and powerful tool to make positive, topographic, and etiologic diagnoses of small bowel obstruction. Good knowledge of some key signs and rigorous analysis of computed tomographic images by radiologists should lead to improved diagnosis and appropriate treatment.     

Presacral epidermoid cyst: imaging findings with histopathologic correlation

Background: The aim of this study was to determine the imaging characteristics of presacral epidermoid cysts and correlate the imaging findings with the histopathologic findings. Methods: We retrospectively reviewed sonographic, computed tomographic, and magnetic resonance examinations in four consecutive patients with a pathologically proven presacral epidermoid cyst. Imaging findings of the presacral epidermoid cyst were correlated with the histopathologic findings. Results: In all four patients, sonography showed a presacral mass with a heterogeneous low echogenicity, and computed tomography showed a discrete well-defined hypodense presacral mass with a thin wall. In the three patients who underwent magnetic resonance imaging, the mass showed a heterogeneous low signal intensity on the T1-weighted image and a high signal intensity with multiple small foci of low signal intensity in the nondependent portion of the mass on the T2-weighted image. These imaging findings correlated well with the pathologic results. Aggregates of keratinous material contributed to these imaging findings. Conclusion: In the diagnosis of the presacral epidermoid cyst, sonographic and magnetic resonance imaging findings may be helpful. Received: 16 May 2000/Accepted: 14 June 2000     

Extrahepatic arterioportal venous fistula: multidetector CT and volume-rendered angiographic imaging

We present a case of unsuspected extrahepatic arterial–main portal venous fistula diagnosed by multiphase computed tomography with three-dimensional volume-rendered computed tomographic angiography. To our knowledge, this entity has not been reported previously in the literature, and it represents an example of pathology that may only be detected and clarified with multiphase imaging with three-dimensional rendering. This finding has great clinical importance in patient management. Received: 9 January 2001/Accepted: 24 January 2001     

Primary splenic malignant lymphoma associated with hepatitis C virus infection

We present two cases of primary splenic malignant lymphoma associated with chronic hepatitis C virus infection detected early by routine follow-up imaging studies. Septumlike structures were seen on postcontrast computed tomography or magnetic resonance imaging, which presented characteristic gross findings. These findings may suggest primary splenic malignant lymphoma during the course of chronic hepatitis C. Received: 17 March 2000/Accepted: 19 April 2000     

Cirrhosis: spectrum of findings on unenhanced and dynamic gadolinium-enhanced MR imaging

The appearance of the cirrhotic liver on computed tomography can be difficult to evaluate and can frustrate the radiologist distinguishing benign from malignant lesions. Hepatic edema, fibrosis, atrophy, and vascular abnormalities are common in the cirrhotic liver and produce derangements in morphology, attenuation, and perfusion, limiting the accurate characterization of hepatic masses. With the development of fast magnetic resonance (MR) sequences and dynamic postgadolinium-enhanced imaging, most hepatic lesions with uncertain etiology on computed tomography can be accurately characterized on MR imaging. We describe MR imaging techniques useful for imaging cirrhosis and its complications. We also illustrate the spectrum of findings in the cirrhotic liver on dynamic gadolinium-enhanced MR imaging, including reticular and confluent fibrosis, fatty infiltration, hemochromatosis, regenerating nodules, dysplastic nodules, hepatocellular carcinoma, and sequela of portal hypertension. Received: 16 November 2000/Revision accepted: 7 February 2001     

Intestinal malrotation as an incidental finding on CT in adults

Background:Intestinal malrotation in adults is usually an incidental finding on computed tomography (CT). We present the CT findings of 18 adult patients with malrotation and discuss the clinical implications. Methods: Abdominal scans of 18 patients (12 women, six men; age range = 15–79 years) with intestinal malrotation were reviewed. Special attention was directed to the location of the superior mesenteric vessels, the location of the small and large bowels, the size of the uncinate process, the situs definition, and additional anomalies. Results: The malrotation was an incidental finding in all but one patient. The malrotation was type Ia in 17 patients and IIc in the one symptomatic patient. The superior mesenteric vessels were vertically oriented in 10, inverted in two, normally positioned in four, and mirror imaged in two cases with situs ambiguus. All patients had aplasia of the pancreatic uncinate process, five had a short pancreas, and two had a preduodenal portal vein. Fourteen patients had a normal situs and four had heterotaxia. Seven patients had polysplenia, six of which with associated inferior vena cava anomalies. Conclusions: Intestinal malrotation can be diagnosed on CT by the anatomic location of a right-sided small bowel, left-sided colon, an abnormal relationship of the superior mesenteric vessels, and aplasia of the uncinate process. Awareness of these abnormalities is necessary to diagnose this anomaly. It should be sought in patients with a situs problem, inferior vena cava anomalies, polysplenia, or preduodenal portal vein. Although usually an incidental finding, it is important to diagnose such a malrotation because it may cause abdominal symptoms. Also, knowledge of associated vascular anomalies is important when abdominal surgery is planned. Received: 1 October 1998/Revision accepted: 27 January 1999