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Asynchronous movement of the carotid atheromatous plaque from B-mode ultrasound has been previously reported, and associated with higher risk of stroke, but not quantitatively estimated. Based on the hypothesis that asynchronous plaque motion is associated with vulnerable plaque, in this study, synchronisation patterns of different tissue areas were estimated using cross-correlations of displacement waveforms. In 135 plaques (77 subjects), plaque radial deformation was synchronised by approximately 50% with the arterial diameter, and the mean phase shift was 0.4 s. Within the plaque, the mean phase shifts between the displacements of the top and bottom surfaces were 0.2 s and 0.3 s, in the radial and longitudinal directions, respectively, and the synchronisation about 80% in both directions. Classification of phase-shift-based features using Random Forests yielded Area-Under-the-Curve scores of 0.81, 0.79, 0.89 and 0.90 for echogenicity, symptomaticity, stenosis degree and plaque risk, respectively. Statistical analysis showed that echolucent, high-stenosis and high-risk plaques exhibited higher phase shifts between the radial displacements of their top and bottom surfaces. These findings are useful in the study of plaque kinematics. © 2020, The Author(s).

Background The diagnosis of bacterial infection in cirrhotic patients may be difficult, because of the absence of classical signs such as fever and raised white blood cell count. The role of C-reactive protein (CRP) in this context has not been clearly defined. Methods Clinical and laboratory characteristics of 210 consecutive cirrhotic patients with (n=100) or without (n=110) bacterial infection were compared with a control group of non-cirrhotic patients with infection (n=106). Results Significantly fewer patients with cirrhosis had a body temperature ≥37°C when presenting with bacterial infection (56% cirrhotic vs. 85.5% non-cirrhotic patients, P=0.01). Mean leukocyte count was 6.92 × 103/mm3 in patients with cirrhosis and infection, 5.75 × 103/mm3 (P=0.02) in cirrhotic patients without infection, and 11.28 × 103/mm3 in non-cirrhotic patients with infection (P10 mg/L indicated the presence of infection with a sensitivity of 68%, a specificity of 84.5% and an area under the receiver operating characteristic curve of 0.8197. CRP cutoff level differed according to the severity of the liver disease: Child-Pugh score (CPS) A: 21.3 mg/L, B: 17 mg/L, and C: 5.78 mg/L. Conclusions CRP at admission could help diagnose infection in cirrhotic patients. Since the severity of liver disease seems to affect the CRP values, lower CRP levels might indicate infection. Clinical suspicion is necessary to avoid delay in diagnosis and initiate antibiotic treatment. © 2018 Hellenic Society of Gastroenterology.

In this paper, three multiscale transforms with directional character, namely the dual-tree complex wavelet (DTCWT), the finite ridgelet (FRIT) and the fast discrete curvelet (FDCT) transforms, were comparatively assessed with respect to their ability to characterize carotid atherosclerotic plaque from B-mode ultrasound and discriminate between symptomatic and asymptomatic cases. The standard deviation and entropy of the detail subimages produced for each decomposition scheme were used as texture features. Feature selection included ranking the features according to their highest separability value and the minimum correlation among them. Due to the rather limited size of the sample population, the selected features were resampled 100times by the bootstrap technique and divided into training and test sets. For each pair of sets, a support vector machine classifier was trained on the training set and evaluated on the test set. The average overall classification performance for systole (diastole) was 70% (65.2%), 72.6% (70.4%) and 84.9% (73.6%) for the DTCWT, FRIT and FDCT, respectively. These preliminary results showed the superiority of the curvelet transform, in terms of classification accuracy, being of great importance for the diagnosis and management of plaque instability in carotid atheromatous stenosis. © 2012 IOP Publishing Ltd.