Acute intestinal anisakiasis: CT findings

Small bowel anisakiasis is a relatively uncommon disease that results from consumption of raw or insufficiently pickled, salted, smoked, or cooked wild marine fish infected with Anisakis larvae. We report a case of intestinal anisakiasis in a 63-year-old woman presenting with acute onset of abdominal complaints one day after ingestion of raw wild-caught herring from the Northsea. Computed tomography (CT) scanning demonstrated thickening of the distal small bowel wall, mucosa with hyperenhancement, mural stratification, fluid accumulation within dilated small-bowel loops and hyperemia of mesenteric vessels. In patients with a recent history of eating raw marine fish presenting with acute onset of abdominal complaints and CT features of acute small bowel inflammation the possibility of anisakiasis should be considered in the differential diagnosis of acute abdominal syndromes.

Noninvasive multidetector computed tomography enterography in patients with small-bowel Crohn's disease: is a 40-second delay better than 70 seconds?

BACKGROUND

Multidetector computed tomography (MDCT) enterography combines neutral enteric contrast with intravenously administered contrast material. The optimal intravenous (IV) contrast material protocol has still not been established.

PURPOSE

To determine the optimal delay time to image patients with small-bowel Crohn's disease during MDCT enterography.

MATERIAL AND METHODS

After oral administration of 1350 ml of neutral contrast medium, 26 patients with small-bowel Crohn's disease underwent MDCT enterography;scans were obtained 40 s (enteric phase) and 70 s (parenchymal phase) after IV administration of 100 ml of iodinated contrast material. Three radiologists, blinded to clinical and pathological findings, independently and retrospectively evaluated each scan in two separate reading sessions for the presence or absence of CT features of Crohn's disease activity. The interobserver agreement was evaluated, and the efficacy of each phase in detecting active disease in the terminal ileum for each reader was determined. The gold standard was pathology (n=13), endoscopy (n=3), and clinical evaluation (n=10).

RESULTS

No statistically significant difference was present between the enteric and the parenchymal phase for each reader in each segment regarding the presence or absence of CT features of Crohn's disease. The interobserver agreement for the presence of five main features of active Crohn's disease in the terminal ileum ranged from poor to excellent.The sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for active Crohn's disease in the terminal ileum ranged from 40 to 90%, 88 to 100%, 70 to 94%, 44 to 100%, and 69 to 96%, respectively. There was no statistical difference between the two phases for each reader.

CONCLUSION

MDCT enterography in patients with suspected active Crohn's disease can be obtained at either 40 s or 70 s after IV contrast material.

Tuberculous adenitis: comparison of CT and MRI findings with histopathological features

Our aim was to investigate the relationship between the various histopathological features and the CT and MRI findings in routinely submitted histopathological specimens for the diagnosis of tuberculous lymphadenopathy. Twelve formalin-fixed, paraffin-embedded tissue blocks from ten patients who were clinically suspected of having tuberculous lymphadenopathy were evaluated. We assessed the presence of histopathological features including granuloma formation, caseous necrosis, and presence of Langhans-type giant cells, calcifications, fibrosis or normal lymphoid tissue. We performed polymerase chain reaction (PCR)-based assay for mycobacterial DNA and Ziehl-Neelsen staining for acid-fast bacilli (AFB). Findings were compared with those of CT and MRI, including signal intensities on unenhanced MR images, lymph node homogeneity, attenuation values on contrast-enhanced CT and enhancement patterns on MRI. Based on CT and MRI findings, four lymph node types could be defined: (1) homogeneous nodes, visible on both pre- and post-contrast images and corresponding histopathologically to granulation tissue without or with minimal caseation necrosis (n = 2); (2) heterogeneous nodes, showing heterogeneous enhancement patterns with central non-enhancing areas and corresponding to minor or moderate intranodal caseation/liquefaction necrosis (n = 3); (3) nodes showing peripheral rim enhancement and corresponding to moderate or extensive intranodal caseation/liquefaction necrosis (n = 5); (4) heterogeneous nodes showing intranodal hyperdensities on CT and hypointense areas on T1- and T2-weighted images and corresponding to fibrosis and calcifications (n = 2). On CT and MRI, the findings reflect different stages of the tuberculous process. Imaging findings depend on the presence and the degree of granuloma formation, caseation/liquefaction necrosis, fibrosis and calcifications.

Tuberculosis: epidemiology, manifestations, and the value of medical imaging in diagnosis

Mycobacterial infections have been shown to be increasing in number worldwide, mainly due a global increase in developing countries, the increased number of patients with HIV infection and AIDS disease worldwide, an increasing number of elderly patients and the emergence of multidrug resistant tuberculosis. Inhalation is the predominant pathway of Mycobacterium tuberculosis (M. tuberculosis) infection, making pulmonary tuberculosis the most common form of tuberculosis. Tuberculosis may arise either from a recent infection with M. tuberculosis, or from the reactivation of dormant bacilli, years or decades after initial infection. Extrapulmonary tuberculosis mainly results from reactivation of a tuberculous focus after hematogenous dissemination or lymphogenous spread from a primary, usually pulmonary focus. Tuberculosis may demonstrate a variety of radiological features depending on the organ site involved and may mimick other pathologies. The final diagnosis of tuberculous disease mainly depends on the detection of the causative organism on histopathological examination, culture and polymerase chain reaction-based assay for mycobacterial DNA on material obtained during bronchoscopic washings, fine needle aspiration cytology (FNAC) or biopsy.

CT and MR imaging of gastrointestinal tuberculosis

The purpose of this study was to describe the CT and MR imaging findings of tuberculosis of the gastrointestinal tract. Abdominal and pelvic CT scans and MRI studies of 6 patients with histopathological and microbiological proven intestinal tuberculosis were reviewed by two radiologists in consensus. Location and pattern of bowel wall involvement, signal intensities in relation to the normal bowel wall, pattern of enhancement and associated abdominal abnormalities were evaluated. Gastrointestinal tract tuberculosis may be limited to one bowel segment, with the cecum and ileocecal valve as the predominant site of disease, or may involve multiple bowel segments. Asymmetric thickening of the bowel wall is a common finding. Associated findings include pericecal and mesenteric fat stranding, regional lymphadenopathy showing peripheral, heterogeneous and/or homogeneous enhancement patterns and less commonly, tuberculous 'dry plastic' peritonitis. On magnetic resonance (MR) imaging, tuberculous bowel involvement results in intermediate decreased signal intensities on T1-weighted images, and intermediate increased, slight heterogeneous signal intensities on T2-weighted images. On contrast-enhanced images, slight heterogeneous enhancement is seen.

Imaging of extraspinal musculoskeletal tuberculosis

Tuberculosis (TB) is still a major cause of significant morbidity and mortality despite universal availability of effective chemotherapy. The emergence of multidrug-resistant mycobacteria along with a worldwide increase in HIV infection has led to a recent surge in the number of patients with TB. TB involves both pulmonary and extrapulmonary sites. Tuberculous spondylitis is the most common form of musculoskeletal TB and accounts for approximately 50% of cases. Extraspinal musculoskeletal TB is among the least common manifestations of TB. It shows a predilection for joints and para-articular areas while isolated soft tissue TB occurs extremely rare. A non-specific, often indolent clinical presentation in conjunction with its low prevalence constitutes obstacles for diagnosis. The differential diagnosis of extraspinal musculoskeletal TB consists of degenerative processes, inflammatory and infectious conditions, primary neoplasms, and metastatic lesions. Early diagnosis and treatment is of utmost importance to prevent serious joint and bone destruction. Radiological assessment of patients with musculoskeletal TB is often the key to adequate diagnosis and early treatment. The purpose of this manuscript is to review the imaging features of extraspinal musculoskeletal TB and to focus on the magnetic resonance imaging (MRI) characteristics of this pathology.

Vascular involvement secondary to tuberculosis of the abdomen

Although involvement of the abdomen is a common site of extrapulmonary tuberculosis, involvement of abdominal vessels with complications is rare after infections with Mycobacterium tuberculosis (M. tuberculosis). Vascular complications may result from direct involvement by M. tuberculosis of the vascular wall or may occur as a consequence of local spreading from a tuberculous mass. We describe the imaging findings in two patients with proven tuberculosis of the abdomen and significant vascular complications. In one patient, "dry plastic" peritonitis and tuberculous lymphadenopathy at the level of the porta hepatis with subsequent encasement and compression of the portal vein resulted in prestenotic dilatation and varicose formation in the upper abdomen. In the other patient, bulky necrotic tuberculous lymphadenopathy, located at the splenic hilum, resulted in encasement with stenosis of the splenic vessels and subsequent splenic infarction.

Abdominal tuberculous lymphadenopathy: MRI features

The aim of this study was to describe the MRI features of abdominal tuberculous lymphadenopathy. MRI studies of 13 patients with abdominal tuberculous lymphadenopathy were reviewed with regard to anatomic distribution and size. Signal intensities, in relation to abdominal wall muscle, on unenhanced T1- and T2-weighted images and patterns of contrast enhancement of lymphadenopathy were evaluated in each patient. In each patient, the largest lymph node with the same imaging characteristic was evaluated. The upper paraaortic region was the most common site of involvement (n=12 patients), followed by the lesser omentum (n=10 patients), the anterior pararenal space (n=9 patients), the lower paraaortic area (n=8 patients), the small bowel mesentery (n=6 patients), the greater omentum (n=2 patients) and the originating site of the inferior mesenteric artery (n=2 patients). The mean lymph node size was 1.8 cm (range 0.5-5 cm). The overall mean lymph node number per patient was 16 (range 2-50). A total of 41 lymph nodes were evaluated in 13 patients. On T2-weighted images, 40 lesions were hyperintense and one lesion was isointense. Nine hyperintense lesions showed a hypointense peripheral rim and seven internal heterogeneïty. Perinodal T2-hyperintensity was present in 23 lesions. The latter finding was valid for all patients. On T1-weighted images, 30 lesions were hypointense and 11 isointense. Nine hypointense lesions demonstrated a hyperintense peripheral rim, and six were heterogeneous. Contrast-enhanced fat-suppressed T1-weighted images demonstrated predominant peripheral enhancement in 28 lesions: (1) peripheral uniform, thin (n=19); (2) thick irregular, complete (n=3); and (3) conglomerate group of nodes showing peripheral and central areas of rim enhancement (n=6). Heterogeneous and homogeneous enhancement was present in ten and three lesions, respectively. Combinations of enhancing patterns in the same nodal group and different nodal groups were seen in eight and nine patients, respectively. Abdominal tuberculous lymphadenopathy may show a variety of signal intensities and patterns of contrast enhancement on MRI. Lymphadenopathy, hypointense on T1-weighted, hyperintense on T2-weighted images with perinodal hyperintensity, and predominant peripheral rimlike enhancement may suggest the diagnosis of tuberculosis.

Tuberculosis of the spine: CT and MR imaging features

Tuberculosis (TB) remains endemic in most of the developing countries. However, a resurgence of tuberculosis has also been reported in the past decades in developed countries, not only in the lungs, but also in extrapulmonary sites, e.g. the vertebral column. Vertebral TB is most often found in the lower thoracic and upper lumbar regions. Diagnosis is often difficult; clinical findings are usually non-specific and radiologic features may mimic those of other bacterial, fungal, inflammatory and neoplastic diseases. However, recognition and understanding of the radiological findings may help in diagnosis. Two distinct patterns of vertebral tuberculosis may be seen: the classic finding of spondylodiscitis, characterized by destruction of two or more contiguous vertebrae and opposed end plates, disk infection, and commonly a paraspinal mass or collection. The second pattern, increasing in frequency, is a atypical form of spondylitis without disk involvement.The value of CT and MR imaging are discussed in the diagnostic workup of vertebral tuberculosis. A positive culture or histopathologic analysis of CT-guided needle aspiration or biopsy specimens is required in the absence of pulmonary manifestations of tuberculosis for definitive diagnosis and adequate treatment.

Tuberculosis of the pancreas: MRI features

OBJECTIVE

The purpose of this study was to describe the MRI features of tuberculosis of the pancreas.

CONCLUSION

Pancreatic tuberculosis can be focal or diffuse. If focal, it presents as a sharply delineated mass located in the pancreatic head, showing heterogeneous enhancement. Lesions are hypointense on fat-suppressed T1-weighted images and a mixture of hypo- and hyperintense on T2-weighted images. The appearances of common bile duct and main pancreatic duct are normal. Diffuse involvement is characterized by pancreatic enlargement with narrowing of the main pancreatic duct and heterogeneous enhancement. Signal intensity abnormalities indicating diffuse involvement include hypointensity on fat-suppressed T1-weighted images and hyperintensity on T2-weighted images.

Clinical and radiological deterioration in a patient with AIDS

Paradoxical clinical deterioration of miliary tuberculosis, characterized by pulmonary and abdominal manifestations, is reported in a patient with the acquired immunodeficiency syndrome, after initiation of treatment with highly active antiretroviral therapy. Paradoxical reaction was attributed to partial restoration of cell-mediated immunity related to highly effective antiretroviral therapy. Because tuberculosis has a high prevalence in HIV patients and tuberculosis is often characterized by miliary spreading of disease in these patients, it is important to recognize this phenomenon.

Picture archiving and communication system--part 2 cost-benefit considerations for picture archiving and communication system

Picture archiving and communication system (PACS) has become an important component of many radiology departments. PACS is expected to make the departments more efficient, reduce operating costs, and improve the communication between the radiologist and the referring physician. Even if the cost-savings are not substantial because of the capital expense of PACS, cost justification is very important in demonstrating the substantial advantages of PACS at either little or no additional expense. Some cost-benefit considerations for PACS are discussed in relation to a hospital-wide implementation.

Picture archiving and communication system: the impact of filmless and distance radiology

The progressive spread of Picture Archiving and Communication System (PACS) in medical imaging constitutes some of the major changes in the radiology and hospital environment during the past decade. The major benefit of PACS resides in its ability to communicate images and reports to referring physicians in a timely and reliable fashion. Filmless radiology offers the opportunity to redesign departmental and enterprise-wide workflow with increase in efficiencies of technologists, clerical staff and radiologists. PACS may improve patient care by providing real-time radiology and by enabling teleradiology. These technologies and the changing environment in radiology may force the radiologists to become more directly involved in the triage and management decisions for the patient. Occasional consultations, regularly scheduled consultation services, and multidisciplinary clinical discussions including a radiologist may help directing physicians to the best sequence of examinations to resolve a clinical problem.

Picture archiving and communication system--Part one: Filmless radiology and distance radiology

Picture archiving and communication system (PACS) is a collection of technologies used to carry out digital medical imaging. PACS is used to digitally acquire medical images from the various modalities, such as computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, and digital projection radiography. The image data and pertinent information are transmitted to other and possibly remote locations over networks, where they may be displayed on computer workstations for soft copy viewing in multiple locations, thus permitting simultaneous consultations and almost instant reporting from radiologists at a distance. Data are secured and archived on digital media such as optical disks or tape, and may be automatically retrieved as necessary. Close integration with the hospital information system (HIS)--radiology information system (RIS) is critical for system functionality. Medical image management systems are maturing, providing access outside of the radiology department to images throughout the hospital via the Ethernet, at different hospitals, or from a home workstation if teleradiology has been implemented.

Considerations for planning and implementation

Installing Picture Archiving and Communication System (PACS) has very wide implications on the radiology department and the hospital as a whole. PACS is an entire hospital investment, which will change many professionals' working practices. Its selection and implementation must involve all the groups it will affect and this demands an appropriate approach. Developing processes that establish the needs of the users, support strategic initiatives, and address risk management is not a minor undertaking. The development of a plan that provides PACS selection committees with a step-by-step roadmap to seek and procure PACS best suited to their workflow is a valuable tool. This review considers the process of planning and implementation for PACS.

Tuberculous epididymitis associated with abdominal lymphadenopathy (2004:1b)

Although the predominant form of tuberculosis is pulmonary disease, an increasing number of cases with extra-pulmonary involvement have been reported. The diagnosis of extra-pulmonary tuberculosis is often difficult because of its protean clinical manifestations and non-specific laboratory findings. Abdominal lymph node involvement may be present alone or in combination with involvement of the gastrointestinal tract, peritoneum, and solid viscera. Tuberculous epididymitis occurs sporadically and represents a specific secondary subacute or chronic inflammatory process involving the epididymis. We present the imaging findings in a patient with tuberculous epididymitis associated with abdominal tuberculous lymphadenopathy.

Asymptomatic nonspecific serum hyperamylasemia and hyperlipasemia: spectrum of MRCP findings and clinical implications

We assessed the magnetic resonance cholangiopancreatographic (MRCP) findings in patients with asymptomatic, mild elevations of serum amylase and lipase levels to determine whether there might be a pathoanatomic cause for these laboratory abnormalities. MRCP was performed in 633 consecutive patients. Of these, 54 (8.5%) images were obtained in patients with asymptomatic serum hyperamylasemia and hyperlipasemia. MRCP was performed on a 1.0-T MR system; breath-hold gradient-recall, half-Fourier acquisition, and rapid acquisition with relaxation enhancement sequences were obtained. Findings were verified by follow-up, biopsy, or surgery. One-sided, large-sample z tests were used to compare the incidence of abnormalities between the study and control groups (579 patients). The pancreas appeared abnormal on MRCP in 31 patients (57%), including the pancreas divisum in 10 patients (18.5%). Other findings included morphologic changes compatible with chronic pancreatitis in nine patients (16.6%) and a healed pancreatic laceration, juxtapapillary duodenal diverticulum, papillary sclerosis, intraductal pancreatic lithiasis, and hemochromatosis in one patient each (1.9%). Small cystic lesions (< 1 cm) within the pancreas were seen in 15 patients (27.8%). In eight patients, these were associated with other abnormalities (pancreas divisum in three patients, chronic pancreatitis in four, and pancreatic laceration in one). No malignancy was diagnosed. The incidences of normal examination (p = 0.01), pancreas divisum (p < 0.005), and a small cystic lesion (p = 0.01) as solitary findings in this subgroup of patients were significantly higher when compared with the remainder of the studied population. Investigation of asymptomatic patients with nonspecific hyperamylasemia and hyperlipasemia by means of MRCP yielded pancreatic findings in more than 50% of these patients. Pancreas divisum was found more often than expected in the general population.

Usual and unusual causes of extrahepatic cholestasis: assessment with magnetic resonance cholangiography and fast MRI

Cholestasis may result from hepatocellular (intrahepatic) disease or biliary tract (extrahepatic) abnormalities. Etiologies causing extrahepatic cholestasis are extremely diverse and invasive procedures, such as endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC), were previously required to establish the diagnosis. Due to refinements of magnetic resonance imaging (MRI) techniques, the patient with extrahepatic cholestasis currently can be evaluated noninvasively, and the information revealed frequently exceeds the findings obtained by ERCP and PTC. In this essay, we illustrate the classic MR cholangiographic (MRC) and MRI features of a variety of disorders causing extrahepatic cholestasis, including non-neoplastic disorders of the biliary tract (congenital abnormalities, infectious processes, iatrogenic disorders, and postsurgical complications) and neoplastic conditions (e.g., tumors of the pancreas, biliary tree, liver, ampulla, and regional lymph nodes). In most cases, familiarity with the key MRC features in addition to information obtained via cross-sectional MR images provide sufficient information for adequate lesion characterization.

Fulminant herpes hepatitis in an immunocompetent pregnant woman: CT imaging features

Fulminant hepatitis due to herpes simplex virus (HSV) is rare in immunocompetent adults. Most reported cases have clearly established pregnancy as a condition that can predispose to disseminated HSV infection. We report a case of a 25-year-old previously healthy pregnant woman who presented with fatigue, fever, and anicteric hepatitis. Triphasic contrast-enhanced computed tomography demonstrated a miliary pattern of multiple, hypovascular, subcentimeter lesions scattered throughout the liver. Familiarity with the clinical findings and computed tomographic appearance may prompt early recognition of fulminant HSV hepatitis and allow differentiation from other hepatic disease during pregnancy.

Fatal, complete splenic infarction and hepatic infection due to disseminated Trichosporon beigelii infection

We report on a 56-year-old woman with acute lymphocytic leukemia who presented with right upper quadrant pain, fever, nausea, and vomiting. Laboratory studies confirmed fungemia with Trichosporum beigelii, and contrast-enhanced computed tomography of the abdomen demonstrated numerous low-attenuation liver lesions and a hypodense spleen with capsular enhancement suggestive of complete splenic infarction. Subsequent splenectomy confirmed that the spleen was completely infarcted and infiltrated with Trichosporum. The patient had a difficult postoperative course and died despite aggressive antifungal therapy.

Glomerulocystic kidney disease: MRI findings

Glomerulocystic kidney disease (GCKD) is a rare form of renal cystic disease characterized by cystic dilation of Bowman's capsule. The imaging findings of small renal cysts with a predominant cortical and subcapsular distribution allows for distinction from other, more common, polycystic kidney diseases. The appearance and distribution of the renal cysts by magnetic resonance imaging allow for a definitive diagnosis of GCKD.

Chronic pancreatitis: diagnostic role of computed tomography and magnetic resonance imaging

The value of computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis and detection of complications in patients with chronic pancreatitis are reviewed. CT and MRI diagnoses are based on changes in the pancreatic duct and parenchyma and on the detection of ductal calculi. Despite technical refinements of these imaging methods, the diagnosis of chronic pancreatitis remains often difficult because of the complexity of the morphologic changes and the false-negative results in the early stages of the disease. This article describes and illustrates the imaging features of chronic pancreatitis classified according to the underlying etiology.

Focal nodular hyperplasia of the liver: detection and characterization with plain and dynamic-enhanced MRI

BACKGROUND

We compared nonenhanced and dynamic gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) appearances of hepatic focal nodular hyperplasia (FNH) as depicted with breath-hold MR sequences and assessed the detectability of the individual MR sequences used.

METHODS

We retrospectively reviewed 48 consecutive patients with FNH. All patients underwent nonenhanced (T1 fast low-angle shot [FLASH] and T2 half-Fourier acquisition [HASTE]) and dynamic Gd-enhanced (T1 FLASH) MRI between December 1997 and March 2000. Individual MR sequences were analyzed separately for number of lesions, signal intensity features, dynamic enhancement pattern, and the presence and enhancement profile of a central scar. Ninety-five percent confidence intervals of absolute discrepancy were calculated to define differences in lesion detection.

RESULTS

Seventy-seven lesions were found in 48 patients. Nonenhanced FLASH imaging depicted 59 (76.6%) lesions in 45 patients. HASTE images showed 55 (71.4%) lesions in 44 patients. On T1- and T2-weighted images, lesions appeared predominantly hypointense (69.5%) and hyperintense (72.7%), respectively. Arterial and portal venous dominant phase Gd-enhanced MRI demonstrated all 77 lesions (100%), most of which showed hypervascular (94.8%), homogeneous (97.4%), and incomplete (except the central scar: 58.4%) enhancement in the arterial phase. Portal venous phase images showed lesion isointensity (50.6%) or moderate hyperintensity (46.8%) with complete enhancement (central scar: 94.8%). A central scar was detected on nonenhanced T1-weighted images (hypointense: 100%), T2-weighted images (hyperintense: 100%), arterial phase (hypointense: 59.7%) and portal venous phase (hyperintense: 71.4%) Gd-enhanced images in 78%, 69.1%, 77.9%, and 75.3% of tumors, respectively.

CONCLUSION

Arterial and portal venous phase Gd-enhanced T1-weighted sequences are superior to nonenhanced images in the detection of FNH. Typical MRI appearances include hypointensity on T1-weighted and hyperintensity on nonenhanced T2-weighted images. Most commonly, FNH shows a homogeneous (without scar) and strong enhancement during the arterial phase, with lesion isointensity or slight hyperintensity during the portal venous phase.

Hepatic veno-occlusive disease: MRI findings

We present magnetic resonance imaging findings in a patient with proven hepatic veno-occlusive disease (VOD) caused by the use of "poppers," a recreational drug used during anal intercourse. Although this report emphasizes the differential magnetic resonance imaging features between VOD and Budd-Chiari syndrome, our case is unique because the VOD was induced by unrelated substances.

Extramedullary paraspinal hematopoiesis in hereditary spherocytosis

Extramedullary hematopoiesis is a rare condition, characterized by the appearance of hematopoietic elements outside the bone marrow. It occurs primarily in patients with chronic myeloproliferative disorder or congenital hemolytic anemia. We report on a 60-year-old man with hereditary spherocytosis who presented with an extramedullary paraspinal hematopoietic mass, splenomegaly, and bone marrow expansion in the right distal femur and proximal tibia metaphysis. The diagnosis was established after biopsy of the paravertebral mass. The patient underwent a splenectomy.

Dynamic gadolinium-enhanced MR imaging of pancreatic VIPoma in a patient with Verner-Morrison syndrome

We describe a rare case of a pancreatic VIPoma diagnosed in a patient presenting with watery diarrhea, hypokalemia, and achlorhydria, the so-called WDHA or Verner-Morrison syndrome. Emphasis is placed on the dynamic gadolinium-enhanced MR profile of the tumor, characteristics which have not been illustrated previously, to the best of our knowledge.

Imaging features of pancreatic neoplasms

Pancreatic masses are common in daily imaging practice. The advent of helical CT and breathold MRI has provided a new impetus to the study of the pancreas not only for the potential of characterizing pancreatic masses and pancreatitis but also because of the more accurate staging of pancreatic neoplasms using this technique. Pancreatic tumors are classified according to its histologic origin. Ductal adenocarcinoma is the most common. Regarding ductal adenocarcinoma, despite the fast evolving imaging techniques promising an earlier diagnosis and an accurate staging, still the prognosis is extremely poor. However, new surgical data indicate that long-term survival although rare, occurs on resected tumors less than 2 cm, without vascular encasement or adenopathy. Logically, early detection and accurate staging of tumors has become the main focussing in pancreatic imaging since it may result in an increase in the survival of these patients. In this context, the role of imaging to identify, characterize and stage pancreatic neoplasms will be described. Furthermore, the key radiological features of a gamut of more uncommon pancreatic neoplasms will be illustrated. These include other exocrine epithelial tumors (anaplastic carcinoma, pancreatoblastoma, acinar cell carcinoma serous cystic pancreatic adenoma, mucinous cystic tumors, intraductal mucinous papillary tumor, and solid pseudopapillary neoplasm), endocrine tumors or islet cell tumors (insulinoma, gastrinoma, gluconoma, vipoma, non-functioning tumors), rare non-epithelial tumors (lymphoma, teratoma) and metastases to the pancreas.

Malignant focal hepatic lesions complicating underlying liver disease: dual-phase contrast-enhanced spiral CT sensitivity and specificity in orthotopic liver transplant patients

The aim of this study was to determine the accuracy of contrast-enhanced biphasic spiral CT as a screening tool in the preoperative evaluation of orthotopic liver transplant (OLT) patients. Spiral-CT examinations were performed before liver transplantation in 53 patients. Scans were retrospectively reviewed and compared with pathologic findings in fresh-sectioned livers. When findings between spiral CT and pathology were discordant, formalized livers were reexamined with lesion-by lesion evaluation. Fresh pathologic evaluation revealed 23 liver lesions (16 HCC, 7 macro-regenerative nodules). Malignancy was identified in 13 of 53 patients (24.5%). Pre-transplantation spiral CT depicted 27 liver lesions (23 HCC, 4 macro-regenerative nodules). Malignancy was suspected in 14 patients (26.4%). In 10 of 53 (18.9%), spiral CT and pathologic evaluation were discordant. Subsequent retrospective pathologic evaluation showed malignancy in 4 additional patients. Spiral CT compared with the retrospective pathologic findings revealed 36 real-negative, 14 real-positive, 0 false-positive, and 3 false-negative patients with malignancy. Sensitivity and specificity of spiral CT in detection of malignancy was 82 and 100%, respectively. Contrast-enhanced biphasic spiral CT is an accurate technique in the evaluation of patients preceding OLT. Routine fresh-sectioned liver pathologic findings are not as sensitive as previously estimated.

Pneumatosis intestinalis and portomesenteric venous gas in intestinal ischemia: correlation of CT findings with severity of ischemia and clinical outcome

OBJECTIVE

The purpose of this study was to analyze the correlation between pneumatosis or portomesenteric venous gas, or both, the severity of mural involvement, and the clinical outcome in patients with small- or large-bowel ischemia.

MATERIALS AND METHODS

CT scans of 23 consecutive patients presenting with pneumatosis or portomesenteric venous gas caused by bowel ischemia were reviewed. The presence and extent of both CT findings were compared with the clinical outcome in all patients and with the severity and extent of ischemic bowel wall damage as determined by surgery (15 patients), autopsy (three patients), or follow-up (five patients).

RESULTS

Seven patients showed isolated pneumatosis, and 16 patients showed portomesenteric venous gas with or without pneumatosis (11 and five patients, respectively). Pneumatosis and portomesenteric venous gas were associated with transmural bowel infarction in 14 (78%) of 18 patients and 13 (81%) of 16 patients, respectively. Nine patients (56%) with portomesenteric venous gas died. Of seven patients with infarction limited to one bowel segment (jejunum, ileum, or colon), only one patient (14%) died, whereas of the 10 patients with infarction of two or three bowel segments, eight patients (80%) died.

CONCLUSION

CT findings of pneumatosis intestinalis and portomesenteric venous gas due to bowel ischemia do not generally allow prediction of transmural bowel infarction, because they may be observed in patients with only partial ischemic bowel wall damage. The clinical outcome of patients with bowel ischemia with these CT findings seems to depend mainly on the severity and extent of their underlying disease.

Cystic focal liver lesions in the adult: differential CT and MR imaging features

Cystic lesions of the liver in the adult can be classified as developmental, neoplastic, inflammatory, or miscellaneous. Although in some cases it is difficult to distinguish these entities with imaging criteria alone, certain cystic focal liver lesions have classic computed tomographic (CT) and magnetic resonance (MR) imaging features, which are important for the radiologist to understand and recognize. Lesions with such features include simple (bile duct) cyst, autosomal dominant polycystic liver disease, biliary hamartoma, Caroli disease, undifferentiated (embryonal) sarcoma, biliary cystadenoma and cystadenocarcinoma, cystic subtypes of primary liver neoplasms, cystic metastases, pyogenic and amebic abscesses, intrahepatic hydatid cyst, extrapancreatic pseudocyst, and intrahepatic hematoma and biloma. Specific CT and MR imaging findings that are important to recognize are the size of the lesion; the presence and thickness of a wall; the presence of septa, calcifications, or internal nodules; the enhancement pattern; the MR cholangiographic appearance; and the signal intensity spectrum. In addition, access to critical clinical information remains extremely important. The most important clinical parameters defined include age and gender, clinical history, and symptoms. An understanding of the classic CT and MR imaging appearances of cystic focal liver lesions will allow more definitive diagnosis and shorten the diagnostic work-up.

The Swedish laparoscopic adjustable gastric banding for morbid obesity: radiologic findings in 218 patients

OBJECTIVE

The objective of this study was to determine the prevalence and radiologic features of postoperative complications after Swedish laparoscopic adjustable gastric banding surgery and to emphasize the role of the radiologist in the follow-up of those patients, especially in the treatment of complications.

MATERIALS AND METHODS

We reviewed the radiologic findings in 218 consecutive morbidly obese patients after laparoscopic placement of the Swedish gastric banding system. Radiographic studies of the stomach (obtained with liquid barium sulfate suspension) were performed before surgery and 1 month after band placement in every patient. Additional studies in symptomatic patients were performed when needed.

RESULTS

Surgical complications found included misplacement of the band (five patients, 2.3%), slippage of the band (17 patients, 7.8%), and pouch enlargement (eight patients, 3.7%). Technical problems encountered were inversion of the access port (three patients, 1.4%), leakage of the device (two patients, 0.9%), and spontaneous decrease of the stoma size caused by gastritis (seven patients, 3.2%) or the hyperosmolar properties of the IV contrast material (12 patients, 5.5%). Intrinsic abnormalities of gastroesophageal tract seen included trapping of food in the stoma (four patients, 1.8%) and esophagitis (11 patients, 5%).

CONCLUSION

Although, according to the available data, the gastric banding operation with the Swedish band meets the criteria of a low-risk laparoscopic alternative treatment of morbid obesity, the radiologic appearances of various complications may be seen on the images of patients who have undergone the procedure. The radiologist plays a key role in the early detection of those complications and treatment of specific abnormalities.

Pancreatocolonic fistula due to severe acute pancreatitis: imaging findings

Colonic involvement is an uncommon but potentially lethal complication of severe acute pancreatitis. The spectrum of colonic complications includes localized ileus with "pseudo-obstruction", obstruction, necrosis, hemorrhage, fistula, and ischemic colitis. We report on a patient who developed pancreatocolonic fistulization in the course of protracted severe acute pancreatitis. Emphasis is made on the computed tomographic and water soluble contrast enema findings.

Magnetic resonance imaging of the exocrine pancreas

The currently available MRI, techniques that are used to perform imaging of the pancreas are reviewed. A basic pancreas examination includes: fat-suppressed breath-hold T1-weighted and respiratory triggered or breath-hold T2-weighted fast sequences The use of dynamic MRI with both extracellular gadolinium chelates and specific contrast agents is stressed in the evaluation of exocrine pancreatic diseases. It is concluded that an "all-in-one" approach including MR angiography of the pancreatic vessels and MR cholangiopancreatography of the biliopancreatic ductal system, confirmed by further studies, is presumably the most cost-effective imaging technique in the evaluation of a vast array of exocrine pancreatic diseases.

Value of MR cholangiography in the evaluation of postoperative biliary complications following orthotopic liver transplantation

The aim of this study was to describe the spectrum of abnormal biliary findings as seen with magnetic resonance cholangiography (MRC) in symptomatic patients after orthotopic liver transplantation (OLT). In our study we included 12 consecutive patients post-OLT who presented with clinical and/or biochemical suspicion of biliary complications. In all patients MRC was performed on a 1.0-T whole-body magnet and breathhold half-Fourier acquired single-shot turbo spin echo and rapid acquisition with relaxation enhancement sequences were used. Diagnostic confirmation was obtained with percutaneous transhepatic cholangiography (PTC; n = 3 patients), endoscopic retrograde cholangiography (ERC; n = 3 patients), or clinical follow-up. A vast array of biliary abnormalities were detected in 11 of 12 patients: high-grade, obstructive, anastomotic stricture was the most common unique abnormality. Findings consistent with bile duct necrosis, the second most common abnormality, were accompanied by arterial abnormalities in 2 of 5 patients on subsequent MR- and digital subtraction angiography. Compared with the findings obtained with direct cholangiography (n = 5 patients), MRC was highly accurate for the detection and characterization of postoperative biliary complications. Compared with the final diagnosis, which was based on PTC-ERC findings and/or all available clinical data, MRC imaging alone was able to provide a specific diagnosis in 9 of 12 patients. Magnetic resonance cholangiography is an accurate, time-saving, and non-invasive imaging modality in the evaluation of post-OLT patients in whom suspicion of biliary complications exists. Although the precise value of MRA in this patient group requires larger dedicated studies, single session "all-in-one" MR evaluation of both biliary and arterial system in our series proved to be a substantial benefit in obtaining an accurate and complete diagnosis.

Splenic and perisplenic involvement in acute pancreatitis: determination of prevalence and morphologic helical CT features

PURPOSE

The purpose of this work was to determine the prevalence and morphologic helical CT features of splenic and perisplenic involvement in patients with acute pancreatic inflammatory disease in correlation with the severity of the pancreatitis.

METHOD

One hundred fifty-nine contrast-enhanced helical CT scans of 100 consecutive patients with acute pancreatitis were reviewed retrospectively and independently by three observers. CT scans were scored using the CT severity index (CTSI): Pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the CTSI and the presence of splenic and perisplenic involvement was calculated (K statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using the Fisher exact test.

RESULTS

The severity of pancreatitis was graded as mild (n = 59 scans), moderate (n = 82 scans), and severe (n = 18 scans). Splenic and perisplenic abnormalities detected included perisplenic inflammatory fluid collections (95 scans, 58 patients), narrowing of the splenic vein (35 scans, 25 patients), splenic vein thrombosis (31 scans, 19 patients), splenic infarction (10 scans, 7 patients), and subcapsular hemorrhage (2 scans, 2 patients). No cases of splenic artery pseudoaneurysm formation, intrasplenic venous thrombosis, intrasplenic pseudocysts, or abscesses were detected. The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of abnormalities was 75.5-79.2 and 71.7-100%, respectively. A statistically significant difference between the presence of abnormalities and the severity of pancreatitis was observed (p < 0.001).

CONCLUSION

Splenic vein thrombosis (19%) and splenic infarction (7%) are relatively common CT findings in association with acute pancreatitis. The CTSI proves to be accurate in predicting these complications as there is a statistically significant correlation between the prevalence of these complications and the severity of pancreatitis.

Renal and perirenal space involvement in acute pancreatitis: spiral CT findings

BACKGROUND

This study was conducted to estimate the prevalence and morphologic computed tomographic (CT) features of renal and perirenal space abnormalities in acute pancreatitis in correlation with the severity of pancreatitis.

METHODS

One hundred fifty-nine contrast-enhanced CT scans of 100 consecutive patients with acute pancreatitis were retrospectively and independently reviewed by three observers. All CT images were obtained using contrast-enhanced helical CT (collimation width = 5 mm, table increment = 7 mm/s, reconstruction interval = 5 mm, scan delay time = 30-50 s). Additional maximized images (field of view = 260 mm) of the perirenal space were available for review. All CT scans were scored with the CT Severity Score Index: pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the severity score and the presence of renal and perirenal involvement was calculated. Correlation between the prevalence of complications and the degree of pancreatitis was estimated.

RESULTS

CT scans were graded as mild (n = 59), moderate (n = 82), and severe (n = 18). Abnormalities detected included perirenal stranding (n = 37 patients, 26 bilateral), perirenal fluid collections (n = 10 patients, one bilateral), ureteral encasement (n = 2 patients), renal vein thrombosis (n = 1 patient), and renal parenchymal abnormalities (n = 1 patient). The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of abnormalities was 75.5-79.2% and 59.8-100%, respectively. Except for stranding of the perirenal fat, no statistically significant differences between the presence of abnormalities and the severity of pancreatitis (moderate or severe) was observed with Fisher's exact test. Also, no preferential left-sided localization of complications was observed.

CONCLUSIONS

The incidence of renal and perirenal complications from acute pancreatitis is higher than previously estimated (7%). We found no significant correlation between the prevalence of major complications and the severity of pancreatitis. These findings are important because these complications may have an impact on therapeutic strategy and can affect prognosis.

Giant intraluminal duodenal diverticulum: conventional barium study and computed tomography findings

A case is reported of an asymptomatic intraluminal duodenal diverticulum (IDD) in a 21-year-old male patient with associated congenital abnormalities. During endoscopy for anemia an ostium in the duodenum was visualized, presumed to be the entry to an extraduodenal diverticulum. Upper gastrointestinal (UGI) barium examination showed, however, findings compatible with IDD. This diagnosis was supported by an abdominal computed tomographic (CT) examination. Surgical resection revealed a web in D2 with coexistent large IDD.

Postoperative findings following the Whipple procedure: determination of prevalence and morphologic abdominal CT features

This study was conducted to determine characteristic CT findings following the Whipple procedure and to evaluate the usefulness of CT in predicting tumor recurrence. Eighty-four postoperative abdominal CT scans and medical records of 43 patients were retrospectively reviewed. Perioperative histopathologic examinations revealed malignancy in 32 patients (74.4 %). Time interval between surgery and CT varied from 13 days to 6 years and 7 months. Common postoperative findings were unopacified anastomotic bowel loops in the porta hepatis (n = 69 scans), perivascular cuffing (n = 42 scans), pneumobilia (n = 40 scans), dilated intrahepatic bile ducts (n = 22 scans), reactive lymphadenopathy (n = 21 scans), and transient fluid collections (n = 20 scans). Postoperative complications were detected on 17 CT scans (20.2 %): generalized ascites (n = 8 patients), deep abscesses (n = 3 patients), wound abscess (n = 1 patient), pancreatitis (n = 1 patient), and pseudomembranous colitis (n = 1 patient). Tumor recurrence appeared in 15 patients (46.8 %) after a mean postoperative period of 11 months (1 month to 3 years): local (9 of 15), regional lymph nodes (9 of 15), and liver metastasis (8 of 15). Detection of generalized ascites more than 30 days after surgery was associated with tumor recurrence in 6 of 6 patients (100 %). Diffuse ascites (> 30 days after surgery) behaved as an early predictive sign of tumor recurrence. In our series CT accuracy for detecting recurrent tumor with CT was 93.5 %. No predilection site for disease recurrence could be determined.

Intratumoral steatosis in focal nodular hyperplasia coinciding with diffuse hepatic steatosis: CT and MRI findings with histologic correlation

Focal nodular hyperplasia (FNH) is a benign tumorlike condition that is thought to be a hyperplastic response to increased blood flow in an arterial malformation rather than a true neoplasm. Radiologically, FNH usually shows typical findings on unenhanced and enhanced computed tomography (CT) and magnetic resonance images (MRI), with atypical features being the exception rather than the rule. We report an unusual case of FNH with extensive fatty infiltration of the lesion illustrated on CT and MRI and proven by histopathology.

An undescribed coexistence of a subserosal exophytic gastric leiomyoma with a serous microcystic pancreatic adenoma

We present the case of a 66-year-old woman with complaints of odynophagia but normal gastro-oesophagoscopic findings. On computed tomographic examination, a presumptive diagnosis of a cystic liver tumor and a microcystic pancreatic adenoma was made. Histopathological examination of the hepatic mass, however, revealed a subserosal exophytic gastric leiomyoma. Considerations to avoid the potential pitfall of diagnosing an exogastric leiomyoma as a liver tumor are emphasized. Moreover, the unique association of an exogastric leiomyoma and a serous microcystic pancreatic adenoma is discussed.

Bilateral adrenal cystic lymphangiomas in nevoid basal cell carcinoma (Gorlin-Goltz) syndrome: US, CT, and MR findings

We present a case of bilateral adrenal cystic lymphangioma in a patient with the Gorlin-Goltz syndrome. This case is unique as it is the first illustrated case (US, CT, and MR findings) of a cystic lymphangioma arising within the adrenal gland. In addition, the coexistence of cystic adrenal lymphangioma with the Gorlin-Goltz syndrome has not been described previously.