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Purpose The purpose of this study was to compare the diagnostic accuracy and inter-reader agreement of unenhanced computed tomography (CT) to those of contrast-enhanced CT for triage of patients older than 75 years admitted to emergency department (ED) with acute abdominal pain (AAP). Patients and methods Two hundred and eight consecutive patients presenting with AAP to the ED who underwent CT with unenhanced and contrast-enhanced images were retrospectively included. There were 90 men and 118 women with a mean age of 85.4 ± 4.9 (SD) (range: 75–101.4 years). Three readers reviewed unenhanced CT images first, and then unenhanced and contrast-enhanced CT images as a single set. Diagnostic accuracy was compared to the standard of reference defined as the final diagnosis obtained after complete clinico-biological and radiological evaluation. Correctness of the working diagnosis proposed by the ED physician was evaluated. Intra- and inter-reader agreements were calculated using the kappa test and interclass correlation. Subgroup analyses were performed for patients requiring only conservative management and for those requiring intervention. Results Diagnostic accuracy ranged from 64% (95% CI: 62–66%) to 68% (95% CI: 66–70%) for unenhanced CT, and from 68% (95% CI: 66–70%) to 71% (95% CI: 69–73%) for both unenhanced and contrast-enhanced CT. Contrast-enhanced CT did not significantly improve the diagnostic accuracy (P = 0.973–0.979). CT corrected the working diagnosis proposed by the ED physician in 59.1% (range: 58.1–60.0%) and 61.2% (range: 57.6–65.5%) of patients before and after contrast injection (P > 0.05). Intra-observer agreement was moderate to substantial (k = 0.513–0.711). Inter-reader agreement was substantial for unenhanced (kappa = 0.745–0.789) and combined unenhanced and contrast-enhanced CT (kappa = 0.745–0.799). Results were similar in subgroup analyses. Conclusion Unenhanced CT alone is accurate and associated with high degrees of inter-reader agreement for clinical triage of patients older than 75 years with AAP in the emergency setting.

Liver diseases have been known to induce changes in systemic hemodynamics and to modify the liver-heart-lung balance. Severe or chronic liver disease may result in several heart or pulmonary complications independently of any other existing cardiac or lung disease. The main liver diseases causing

Liver perfusion imaging is a quantitative functional investigation. Liver perfusion imaging is complicated because of the liver's dual vascular supply, artefacts due to respiratory movements and the fenestrated sinusoidal capillaries which allow the contrast medium to diffuse out. Liver perfusion can be examined by ultrasound, CT or MRI: each technique has its limitations and specific features. The major indications in hepatology are oncology (detection, characterization and tumor response) and non-invasive investigation of patients with chronic liver disease. Work is needed to standardize acquisition and modeling methods to allow wider use of results and more widespread use of the technique.

Background Visual semi-quantitative assessment of liver tumour burden for neuroendocrine tumour liver metastases is often used in patient management and outcome. However, published data on the reproducibility of these evaluations are lacking. Objective The aim of this study was to evaluate the interobserver and intraobserver agreement of a visual semi-quantitative assessment of liver tumour burden using CT scan. Methods Fifty consecutive patients (24 men and 26 women, mean aged 54 years) were retrospectively reviewed by four readers (two senior radiologists, one junior radiologist and one gastroenterologist) who assessed the liver tumour burden based on a visual semi-quantitative method with four classes (0–10, 11–25, 26–50 and ≥50%). Interobserver and intraobserver agreement were assessed by weighted kappa coefficient and percentage of agreement. The intraclass correlation was calculated. Results Agreement among the four observers for the evaluation of liver tumour burden was substantial, ranging from 0.62 to 0.73 (P P Conclusion Reproducibility of the visual semi-quantitative evaluation of liver tumour burden is good and is independent of the level of experience of the readers. We therefore suggest that clinical studies in patients with neuroendocrine liver metastases use this method to categorise liver tumour burden.

Early detection of pancreatic adenocarcinoma is the goal of imaging, enabling curative surgery. The identification of high-grade dysplastic precursor lesions is even more beneficial. Two forms are now better known: pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasm (IPMN). To detect these lesions with imaging, we need to know the patterns associated with them. A screening program could then be used to pinpoint them. This program could not be applied to the entire population. Identifying patients with an increased risk of pancreas adenocarcinoma is the first step of such screening.

International audience; To compare the value of enhancement and pharmacokinetic parameters measured at dynamic gadoxetate-enhanced magnetic resonance (MR) imaging in determining hepatic organic anion transporter expression in control rats and rats with advanced liver fibrosis.Institutional animal review board approval was received before the study began. Advanced liver fibrosis was created in rats by means of carbon tetrachloride injections over an 8-week period. In 17 rats with liver fibrosis and eight control rats, dynamic gadoxetate-enhanced MR images of the liver were obtained during 1 hour after injection of 0.025 mmol gadoxetate per kilogram of body weight. Enhancement parameters (maximum enhancement [Emax], time to peak [Tmax], and elimination half-life) were measured on enhancement-versus-time curves, and pharmacokinetic parameters (hepatic extraction fraction [HEF] and mean residence time [MRT]) were obtained by means of deconvolution analysis of the concentration-versus-time curves in the liver and the portal vein. The parameters were correlated at simple and multiple regression analysis with the expression of the hepatic anion uptake transporter organic anion-transporting polypeptide 1A1 (Oatp1a1), the hepatobiliary transporter multidrug resistance–associated protein 2 (Mrp2), and the backflux transporter Mrp4, as determined with reverse transcription polymerase chain reaction.In rats with advanced liver fibrosis, the Emax, Tmax, HEF, and MRT decreased significantly relative to those in control rats, whereas the elimination half-life increased significantly. The enhancement and pharmacokinetic parameters correlated significantly with the expression of the transporters at simple regression analysis. At multiple regression analysis, HEF was the only parameter that was significantly associated with the expression of Oatp1a1 and Mrp2 (P < .001, r = 0.74 and P < .001, r = 0.70, respectively).The pharmacokinetic parameter HEF at dynamic gadoxetate-enhanced MR imaging is independently correlated with hepatic organic anion transporter expression.

Our objective was to determine the diagnostic accuracy of a free-breathing diffusion-weighted single-shot echo-planar magnetic resonance imaging (FBDW-SSEPI) technique with parallel imaging and high diffusion factor value (b = 1000 s/mm2) in the detection of primary rectal adenocarcinomas. Thirty-one patients (14M and 17F; mean age 67 years) with histopathologically proven primary rectal adenocarcinomas and 31 patients without rectal malignancies (14M and 17F; mean age 63.6 years) were examined with FBDW-SSEPI (repetition time (TR/echo time (TE) 3900/91 ms, gradient strength 45 mT/m, acquisition time 2 min) at 1.5 T using generalized autocalibrating partially parallel acquisitions (GRAPPA, acceleration factor 2) and a b value of 1000 s/mm2. Apparent diffusion coefficients (ADCs) of rectal adenocarcinomas and normal rectal wall were measured. FBDW-SSEPI images were evaluated for tumour detection by 2 readers. Sensitivity, specificity, accuracy and Youden score for rectal adenocarcinoma detection were calculated with their 95% confidence intervals (CI) for ADC value measurement and visual image analysis. Rectal adenocarcinomas had significantly lower ADCs (mean 1.036 x 10(-3)+/- 0.107 x 10(-3) mm2/s; median 1.015 x 10(-3) mm2/s; range (0.827-1.239) x 10(-3) mm2/s) compared with the rectal wall of control subjects (mean 1.387 x 10(-3)+/- 0.106 x 10(-3) mm2/s; median 1.385 x 10(-3) mm2/s; range (1.176-1.612) x 10(-3) mm2/s) (p < 0.0001). Using a threshold value < or = 1.240 x 10(-3) mm2/s, all rectal adenocarcinomas were correctly categorized and 100% sensitivity (31/31; 95% CI 95-100%), 94% specificity (31/33; 95% CI 88-100%), 97% accuracy (60/62; 95% CI 92-100%) and Youden index 0.94 were obtained for the diagnosis of rectal adenocarcinoma. FBDW-SSEPI image analysis allowed depiction of all rectal adenocarcinomas but resulted in 2 false-positive findings, yielding 100% sensitivity (31/31; 95% CI 95-100%), 94% specificity (31/33; 95% CI 88-100%), 97% accuracy (60/62; 95% CI 92-100%) and Youden index 0.94 for the diagnosis of primary rectal adenocarcinoma. We can conclude that FBDW-SSEPI using parallel imaging and high b value may be helpful in the detection of primary rectal adenocarcinomas.