Marc Zins

Preoperative cyst fluid analysis is useful for the differential diagnosis of cystic lesions of the pancreas.

BACKGROUND/AIMS It has been suggested that activity of pancreatic enzymes and concentrations of tumoral markers in cyst fluid may help to distinguish pseudocyst, serous, and mucinous cystadenomas. The aim of this study was to prospectively assess the reliability of preoperative biochemical and tumor marker analysis in cyst fluids obtained by fine-needle aspiration for pathological diagnosis. METHODS Cyst fluid was obtained preoperatively by fine-needle aspiration, and biochemical and tumoral marker values were measured. The diagnosis of cystic tumors (7 serous cystadenomas and 12 mucinous tumors) was established by surgical specimen analysis. Thirty-one pancreatic pseudocysts complicating well-documented chronic pancreatitis were also studied. RESULTS Carbohydrate antigen 19.9 levels of > 50,000 U/mL had a 75% sensitivity and a 90% specificity for distinguishing mucinous tumors from other cystic lesions. Carcinoembryonic antigen levels of < 5 ng/mL had a 100% sensitivity and an 86% specificity for distinguishing serous cystadenomas from other cystic lesions. Amylase levels of > 5000 U/mL had a 94% sensitivity and a 74% specificity for distinguishing pseudocysts from other cystic lesions. CONCLUSIONS High carbohydrate antigen 19.9, low carcinoembryonic antigen, and high amylase levels in cyst fluid are very indicative of mucinous tumors, serous cystadenomas, and pseudocysts, respectively.

Diagnostic Imaging of Solitary Tumors of the Spine: What to Do and Say

Metastatic disease, myeloma, and lymphoma are the most common malignant spinal tumors. Hemangioma is the most common benign tumor of the spine. Other primary osseous lesions of the spine are more unusual but may exhibit characteristic imaging features that can help the radiologist develop a differential diagnosis. Radiologic evaluation of a patient who presents with osseous vertebral lesions often includes radiography, computed tomography (CT), and magnetic resonance (MR) imaging. Because of the complex anatomy of the vertebrae, CT is more useful than conventional radiography for evaluating lesion location and analyzing bone destruction and condensation. The diagnosis of spinal tumors is based on patient age, topographic features of the tumor, and lesion pattern as seen at CT and MR imaging. A systematic approach is useful for recognizing tumors of the spine with characteristic features such as bone island, osteoid osteoma, osteochondroma, chondrosarcoma, vertebral angioma, and aneurysmal bone cyst. In the remaining cases, the differential diagnosis may include other primary spinal tumors, vertebral metastases and major nontumoral lesions simulating a vertebral tumor, Paget disease, spondylitis, echinococcal infection, and aseptic osteitis. In many cases, vertebral biopsy is warranted to guide treatment.

Craniocervical Arterial Dissection: Spectrum of Imaging Findings and Differential Diagnosis

Craniocervical artery dissection is a potentially disabling yet probably underrecognized condition that often occurs in young and middle-aged adults. Accurate and prompt diagnosis of this condition is crucial because timely and appropriate therapy can significantly reduce the risk of stroke and long-term sequelae. Because of the great diversity in the clinical features of craniocervical artery dissection, imaging plays a primary role in its diagnosis. The increased diagnosis of this disorder in the past two decades can be attributed to an increased awareness of the clinical manifestations of internal carotid artery and vertebral artery dissection and to use of noninvasive diagnostic imaging techniques. To achieve an accurate diagnosis of craniocervical artery dissection, it is important to be familiar with its pathologic features (intimal tear, intramural hematoma, and dissecting aneurysm); the spectrum of imaging findings at color duplex ultrasonography, computed tomographic angiography, magnetic resonance (MR) imaging with MR angiography, and conventional angiography; and potential pitfalls in image interpretation.

Cystic dystrophy of the duodenal wall in the heterotopic pancreas: radiopathological correlations.

Purpose The purpose of this work was to correlate the CT features of cystic dystrophy in heterotopic pancreas (CDHP) with pathological features. Methods Patients were selected from 190 patients who underwent pancreaticoduodenectomy over a 10 year period in our institution. CT findings were retrospectively analyzed in 20 cases and correlated with pathological findings. Results Lesions were found to be located in the inner part of the second portion of the duodenum in all except one case. In all cases, the duodenal wall was thickened, both at CT and at histopathological examination, and moderate to strong contrast enhancement of the duodenal wall was noted at CT in all cases but one. Cysts were multiple in all cases. No heterotopic pancreas was identified with CT. Inflammatory changes with or without enlarged nodes were detected on CT in 15 of 20 cases. Chronic pancreatitis was present in 10 cases at pathology, including 5 cases with calcifications. The radiopathological correlation was excellent for all criteria but two: the size of the cysts and the extent of pyloric involvement. Conclusion In patients with CDHP, CT features correlate well with pathological results. Multiple cysts located in an enlarged duodenal wall with postcontrast enhancement and inflammatory changes are strongly suggestive of CDHP.

Radiologic features of papillary adenoma and papillomatosis of the biliary tract

Abstract.Background: The purpose of this study was to describe the imaging findings of papillary adenoma of the bile ducts. Methods: Imaging modalities including sonography, computed tomography, cholangiography, and endoscopic sonography obtained in five patients with papillary adenoma of the bile duct were retrospectively reviewed and correlated with pathologic findings. Results: In four cases, imaging findings were a dilatation of the bile ducts due to a protruding mass within the lumen of the common bile duct. In one case, the biliary tract obstruction was not due to the mass but to mucus secretion that was detected at sonography, endoscopic sonography, and cholangiography. Multiple lesions were observed in two cases at pathology and not detected preoperatively. All the lesions contained foci of in situ carcinoma or mild dysplasia. Conclusion: Imaging is useful in detecting bile duct tumors. Hypersecretion of mucus is rare but highly characteristic of bile duct adenoma.

Increased Unenhanced Bowel-Wall Attenuation at Multidetector CT Is Highly Specific of Ischemia Complicating Small-Bowel Obstruction

PURPOSE To evaluate performance of increased bowel-wall attenuation on unenhanced 64-section multidetector computed tomographic (CT) images for diagnosing bowel-wall ischemia in patients with mechanical small-bowel obstruction (SBO) and to evaluate the diagnostic accuracy of multidetector CT in detecting small-bowel ischemia complicating SBO, with surgical and histopathologic findings as reference standard. MATERIALS AND METHODS The local institutional review board approved this retrospective study; informed consent requirement was waived. In 44 patients (10 men, 34 women; age range, 30-100 years) who were admitted because they were suspected of having SBO and treated surgically within the next 7 days, 45 multidetector CT scans were retrospectively reviewed. Two gastrointestinal radiologists performed independent blinded reviews of images to identify specific signs of ischemia; disagreements were resolved in consensus with a third gastrointestinal radiologist. Results were compared with both findings in prospective radiology reports and surgical and histopathologic findings. Fisher exact and χ(2) tests were used to assess associations between CT signs and ischemia, and the κ statistic was used to assess interobserver agreement. RESULTS In 19 of 45 (42%) multidetector CT scans, ischemia was confirmed at surgery and/or histopathologic examination. Increased bowel-wall attenuation on unenhanced images was significantly associated with ischemia (P < .0001); in this highly selected population, this sign had a 100% (24 of 24) specificity and a 56% (10 of 18) sensitivity. Sensitivity and specificity of multidetector CT for ischemia were 63% (12 of 19) and 92% (24 of 26), respectively, for the prospective reports and 84% (16 of 19) and 96% (25 of 26), respectively, for the consensus review. Decreased segmental bowel-wall enhancement was the most accurate 64-section multidetector CT sign for diagnosing ischemia (sensitivity, 78% [14 of 18]; specificity, 96% [24 of 25]; P < .0001). The small-bowel feces sign was significantly associated with ischemia (P = .0308). CONCLUSION Increased bowel-wall attenuation on unenhanced 64-section multidetector CT images is a specific sign for ischemia complicating SBO. Diagnostic accuracy of 64-section multidetector CT for ischemia associated with SBO was excellent.

Helical CT of Pancreatic endocrine tumors

Pancreatic endocrine tumors are rare neoplasms. It is important to distinguish them from the more common ductal adenocarcinoma of the pancreas because they are slowly progressive and specific treatments are available. The CT findings of pancreatic endocrine tumors usually vary according to the functioning or nonfunctioning status. In this article, the authors illustrate typical and atypical CT findings of pancreatic endocrine tumors with radiopathologic correlations and give examples of other pancreatic conditions mimicking pancreatic endocrine tumors.

Imagerie de l’adénocarcinome du pancréas

Resume Le cancer du pancreas reste la quatrieme cause de mortalite par cancer. La chirurgie reste le seul traitement permettant une guerison. Un diagnostic et un bilan d’extension precis sont imperatifs pour une prise en charge adaptee des patients ayant un cancer du pancreas. Cet article detaille l’apport de chacune des techniques d’imagerie moderne au diagnostic et au bilan d’extension de l’adenocarcinome pancreatique. Le role central de la TDM s’est renforce avec l’apparition des scanners multicoupes.

Asymptomatic Progressive Multifocal Leukoencephalopathy Associated with Natalizumab: Diagnostic Precision with MR Imaging.

PURPOSE To determine diagnostic precision with magnetic resonance (MR) imaging of the brain, the most predictive MR imaging features, and the added value of comparison with previous data for the diagnosis of asymptomatic progressive multifocal leukoencephalopathy (PML) associated with natalizumab (NTZ). MATERIALS AND METHODS This retrospective study was approved by the institutional review board, and written informed consent was obtained. Eleven consecutive patients with multiple sclerosis (MS) who had received a definitive diagnosis of asymptomatic NTZ-associated PML (NTZ PML, 18 brain lesions) underwent 3-T MR imaging. The control group included 40 patients with MS but without PML who were treated with NTZ. Three readers independently performed blinded analysis of MR images. First, the readers were asked to detect NTZ PML lesions without comparing current images with previously obtained MR imaging data by evaluating MR images for the following features: U fiber and/or cortex involvement, lesion signal intensity and borders, and occurrence of punctate lesions. Second, they reassessed NTZ PML lesions with all the previous MR imaging data available. Diagnostic precision with MR imaging was assessed with and without comparison with previously obtained data. Logistic regression analyses were performed to identify the association of MR imaging features with NTZ PML. RESULTS Overall interobserver agreement was good (κ = 0.76; 95% confidence interval [CI]: 0.71, 0.81). Hyperintensity on diffusion-weighted images and involvement of U fibers were the most predictive features (odds ratio, 33.7; 95% CI: 4.9, 229.7 [P < .0001] and odds ratio, 8.7; 95% CI: 1.2, 61.4 [P = .03], respectively), while punctate lesions were exclusively observed in patients with NTZ PML. Comparison with previous MR imaging data improved specificity of MR imaging for the detection of NTZ PML lesions (from 88% to 100%, P = .05). CONCLUSION Recognition of the most predictive imaging features and comparison with previous MR imaging data may facilitate the detection of asymptomatic NTZ PML.

Punctate pattern A promising imaging marker for the diagnosis of natalizumab-associated PML

Objective: To evaluate the usefulness of the punctate pattern (PP) for the diagnosis and follow-up of patients with progressive multifocal leukoencephalopathy (PML). Methods: A cohort of 20 consecutive patients with PML, related to natalizumab (NTZ) (n = 14) or not (n = 6), underwent 3T MRI (147 MRI examinations). MRI was available at presymptomatic (n = 9 patients), symptomatic (n = 15), immune reconstitution inflammatory syndrome (IRIS), and chronic stages (n = 20). A pathologic control group of patients without PML (n = 80), with clinically definitive multiple sclerosis or a clinically isolated syndrome suggestive of CNS demyelination, underwent the same MRI protocol. Number and appearance of punctate lesions were assessed by 3 blinded readers using T2-weighted, fluid-attenuated inversion recovery (FLAIR), and postcontrast T1-weighted images. Results: Interobserver agreement was good (κ = 0.79) (0.72–0.87). Of the 20 patients with PML, 18 had PP, including the 14 patients with NTZ-PML; none in the pathologic control group. Of the 9 presymptomatic patients with NTZ-PML, PP was observed in 7 (78% sensitive and 100% specific). Nonenhancing PP on T2-weighted/FLAIR images was detected in 13 patients with PML, exclusively at the presymptomatic or symptomatic stages (including 7 NTZ-PML), whereas enhancing PP occurred in 16 patients with PML, including 13 of the 14 patients with NTZ-PML at the IRIS stage. Conclusions: PP is a highly specific feature of PML and may be the first imaging feature at the presymptomatic stage with potential implications in patient care. Classification of evidence: This study provides Class II evidence that a PP on MRI accurately identifies patients with NTZ-PML.