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The aim of our study was to compare whole-body MRI (Magnetic Resonance Imaging) with a multi-contrast protocol including a DW (Diffusion Weighted) sequence to PET-CT (Positron Emission Tomography) using (18)FDG (18F-fluoroDeoxyGlucose) for staging advanced melanoma. In a first part, we compared the respective overall accuracy of each modality. We analyzed in a second part the benefits of a DW sequence added to the standard whole-body MRI protocol. Among the population of the 35 patients who experienced the two examinations of our prospective blinded study, we were able to detect 120 lesions and 70 of them were found malignant. The sensitivity and specificity for whole-body MRI were respectively 82% and 97%, while PET-CT reached 72.8% and 92.7%. DW sequence allowed the detection of 14 supplementary malignant lesions (20%) in comparison with standard MRI protocol. Moreover, this technique has been shown to be the most accurate for detecting metastases in the liver, bone, subcutaneous and intra-peritoneal sites. Consequently, a DW sequence should be added systematically to the standard whole-body MRI oncologic protocol because of its high added-value for metastasis detection., (Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.)

Mangafodipir trisodium (Teslascan) is a hepatobiliary contrast agent that provides noninvasive opacification of the bile ducts. Using this contrast medium combined with a T1-weighted gradient echo enhanced sequence provides functional imaging of the bile ducts. Second-intention MRI was obtained after the usual morphological study of the bile ducts using heavily T2-weighted sequences (SS-FSE Te eff long and SS FSE Te eff short). This method can detect many biliary duct anomalies: biliary leakage in the postoperative context, mapping of bile ducts and the gallbladder in the search for anatomical variants, analysis of biliodigestive or biliobiliary anastomoses, or a dynamic study of bile secretion and excretion. Opacification of the bile ducts has only been possible until now with invasive tests aggravated by a certain co-morbidity rate and their functional study using biliary scintigraphy limited by mediocre spatial resolution. This new possibility provides access not only to morphological imaging, but also to functional imaging with excellent spatial resolution.

Purpose: To evaluate the accuracy of dynamic, contrast material-enhanced computed tomography (CT) in the diagnosis of acute mesenteric ischemia., Materials and Methods: Reviewers blinded to patient diagnoses retrospectively compared the CT scans in a study group with those in a control group. The study group comprised 39 consecutive patients (23 men, 16 women; aged 55-88 years) with surgically proved acute mesenteric ischemia. The control group comprised 24 patients (13 men, 11 women; aged 50-82 years) with suspected acute mesenteric ischemia that was disproved at surgery., Results: For the diagnosis of acute mesenteric ischemia, each of the following findings had a specificity of more than 95% and a sensitivity of less than 30%: arterial or venous thrombosis, intramural gas, portal venous gas, focal lack of bowel-wall enhancement, and liver or splenic infarcts. When CT was used in the diagnosis of suspected acute mesenteric ischemia, the detection of at least one of these signs resulted in a sensitivity of 64% (25 of 39; confidence interval, 0.49, 0.79), a specificity of 92% (22 of 24; confidence interval, 0.81, 1.00), and an accuracy of 75% (47 of 63; confidence interval, 0.64, 0.86)., Conclusion: Dynamic, contrast-enhanced CT is a valuable tool in the diagnosis of and determination of prognosis in acute mesenteric ischemia.