Critical-state parameters of an unsaturated residual clayey soil from Turkey

WOS: 000250657400001This paper deals with the evaluation of the critical-state parameters with respect to the matric suction for saturated and unsaturated undisturbed residual clayey soils from Turkey. In order to conduct the unsaturated triaxial compression testing procedures a conventional triaxial compression apparatus was redesigned. The data for critical-state conditions from these tests are presented with respect to matric suction, based on the critical-state parameters of M, q(0), Gamma, lambda, which is commonly proposed by many authors. The critical state of the unsaturated samples is compared with that of the saturated samples. This experimental study has demonstrated that matric suction has no influence on parameters of M and lambda. The parameters of M and lambda are approximately 0.85 and 0.074 respectively for saturated and unsaturated conditions. The relationships between matric suction (u(a)-u(w)) and the intercepts q(0) and Gamma have been observed as nonlinear, and thus they can be defined as a function of matric suction (u(a)-u(w)). Furthermore, a method is developed to predict the intercepts q(0) according to matric suction for unsaturated clayey soils. (c) 2007 Elsevier B.V. All rights reserved

Magnetic resonance enterography with oral mannitol solution: Diagnostic efficacy and image quality in Crohn disease

Purpose The aim of this study was to investigate the diagnostic efficacy and image quality of magnetic resonance enterography (MRE) using oral mannitol solution for the evaluation Crohn disease (CD). Materials and methods We retrospectively evaluated MRE examinations of 153 patients with an assumed or definitive diagnosis of CD. There were 65 men and 88 women, with a mean age of 35.7 years (range: 6–73 years). MRE findings of the patients were compared to histopathologic results obtained by surgery-fiberoptic endoscopy. The sensitivity, specificity and diagnostic efficacy rate were calculated. Additionally, image quality of MRE was evaluated using a four-point scale (1 = excellent, 4 = poor/non-diagnostic). Results Sensitivity, specificity and diagnostic efficacy were 92.5%, 93% and 92.8%, respectively. Six patients had false-positive and five patients had false-negative findings. Three falsely positive patients had ulcerative colitis and three had non-specific terminal ileitis. A total of 765 small bowel segments were analyzed; 475 (62%) had an image quality score of 1 and 15 (2%), an image quality score of 4. Conclusion MRE using oral mannitol solution provides excellent image quality for MRE and has high degrees of diagnostic efficacy in CD patients. © 2017 Editions françaises de radiologi

Diagnostic accuracy and effective radiation dose of high pitch dual source multidetector computed tomography in evaluation of coronary artery bypass graft patency

Objective: The aim of the study was to evaluate the diagnostic accuracy and effective radiation dose (ERD) of high pitch dual source multidetector computed tomography (MDCT) for coronary artery bypass graft (CABG) patency. Materials and methods: Fourty-five patients who underwent 128 × 2-slice MDCT angiography with a prospective electrocardiogram-triggering, low-dose, high pitch, dual source, flash spiral acquisition mode after CABG surgery were included in the study. The interobserver agreement of the image quality was evaluated with Cohen ? value. The image quality was compared to the heart rates (HRs) using Mann–Whitney U test and to the graft segments using ? 2 test. The findings for the CABG patency on MDCT were compared to those determined on catheter coronary angiography. Dose-length product (DLP) and ERD were compared to the gender, HRs, and body mass index (BMI) of the patients using Kruskall Wallis and Mann–Whitney U tests. Results: A total of 110 grafts and 330 vessel segments were evaluated with a good interobserver agreement (? = 0.80). The image quality was better in proximal and middle graft segments (p < 0.05), as well as in the patients with low HRs (p < 0.05). High pitch MDCT had the following sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for evaluation of graft patency: 92.8, 99.3, 92.8, 99.3 and 98.8 %, respectively. ERD was correlated to the HRs and BMI. Conclusions: High pitch 128 × 2-slice dual source CT angiography is a noninvasive imaging modality, and it can be safely and effectively used in evaluation of CABG patency with lower radiation dose. © 2016, Springer-Verlag Wien

Congenital and acquired renal arteriovenous malformations: Curative embolization with onyx

Renal arteriovenous malformations are rare, as is their embolization with Onyx. Endovascular curative embolization of renal arteriovenous malformations with Onyx is a relatively new procedure. Herein we present two cases of congenital and one case of acquired renal arteriovenous malformation embolized with Onyx 18 and their good results in the follow-up period. We used detachable microcatheters, which may be more advantageous than the nondetachable ones, during the superselective embolizations. Onyx, as an efficient embolic material, can be commonly used for curative embolization of the renal arteriovenous malformations. © 2016, Tehran University of Medical Sciences and Iranian Society of Radiology

The incidence of contrast medium-induced nephropathy following endovascular aortic aneurysm repair: assessment of risk factors

Purpose: The aim of the study was to investigate the incidence of contrast medium-induced nephropathy (CIN) and risk factors for CIN following endovascular abdominal aortic aneurysm repair or thoracic endovascular aortic aneurysm repair. Materials and methods: After exclusion criteria, 139 (121 males, 18 females) patients aged 20–86 (median 65.5) years who underwent endovascular aortic aneurysm repair between January 2002 and September 2013 were included in this retrospective study. CIN, with ?25 % increase in serum creatinine levels within 3 days after contrast medium administration, was compared to the patients’ demographics, risk factors, type and complexity of the endovascular operation, parameters regarding to the contrast medium, preoperative estimated glomerular filtration rate (eGFR), and preoperative and early postoperative serum parameters. Statistical analyses were performed with Kolmogorov-Smirnov, ?2 and Student’s t tests. Results: CIN, detected in 39 of 139 patients (28 %), was correlated with preoperative eGFR <60 ml/min/1.73 m2 (P = 0.04) and high preoperative and postoperative serum urea and creatinine levels. Postoperative serum urea levels (P < 0.001) were significant in multivariate analysis. Conclusion: In patients undergoing endovascular aortic aneurysm repair, CIN was correlated with preoperative and postoperative renal impairment, while it was not correlated with the contrast medium dose. © 2015, Japan Radiological Society

Imaging findings of pulmonary granulomatosis with polyangiitis (Wegener’s granulomatosis): lesions invading the pulmonary fissure, pleura or diaphragm mimicking malignancy

PubMed ID: 25860849Background: Granulomatosis with polyangiitis (GPA, formerly Wegener’s granulomatosis), in which pulmonary involvement often predominates, is a multisystem granulomatous, necrotizing vasculitis that affects small and medium-sized vessels. In this study we evaluated various radiological findings of pulmonary GPA and focused on spiculated pulmonary lesions invading the pulmonary fissure, pleura or diaphragm mimicking malignancy. Methods: This retrospective study included 48 patients, aged 28–73 (mean, 47.3) years, who showed either histopathological diagnosis of GPA (n = 39) or elevated levels of the cytoplasmic anti-neutrophilic cytoplasmic antibody serum marker (n = 9) between January 2003 and December 2013. All patients received a chest computed tomography (CT), and the types of pulmonary lesions were defined and evaluated. Results: Among the 48 patients, 33 had abnormal pulmonary findings on CT. The most commonly detected pulmonary lesion types were nodules and masses (n = 126) observed in 24 patients. Cavitation, necrosis, spiculation and invasion of the fissure, pleura or diaphragm were observed in 14, 9, 10 and 6 patients, respectively. Consolidation was found in 14 patients and thickening of bronchial wall in 8 patients. Conclusions: Pulmonary lesion types of GPA have a wide spectrum, potentially mimicking a high number of diseases including malignancy, infection and noninfectious inflammatory diseases. A spiculated lung lesion invading the fissure, pleura or diaphragm is mostly present in malignancy, but it can be also seen in GPA. © 2015, Springer-Verlag Wien