Search results for " tomography"

INVERSION TESTS ON ULTRASONIC TOMOGRAPHY DATA

2010

3D Ultrasonic Tomography for non-destructive test and for diagnostic study works of art is a rather established methodology. This method allow us to locate, within the volume of work of art, areas of structural non homogeneities, areas of decay, fracture or damaged. This work wants to present some tests carried out to optimize these parameters in order to obtain a better anomaly image resolution for the case history presented. The optimization of these parameters allows locating structural non homogeneity areas, fractures or damages, within the volume, according to shape and type of the investigated anomalies.

From Feynman–Kac formulae to numerical stochastic homogenization in electrical impedance tomography

2016

In this paper, we use the theory of symmetric Dirichlet forms to derive Feynman–Kac formulae for the forward problem of electrical impedance tomography with possibly anisotropic, merely measurable conductivities corresponding to different electrode models on bounded Lipschitz domains. Subsequently, we employ these Feynman–Kac formulae to rigorously justify stochastic homogenization in the case of a stochastic boundary value problem arising from an inverse anomaly detection problem. Motivated by this theoretical result, we prove an estimate for the speed of convergence of the projected mean-square displacement of the underlying process which may serve as the theoretical foundation for the de…

CT angiography for the assessment of EVAR complications : a pictorial review

2022

Aortic aneurysm; Blood vessel prosthesis implantation; Endovascular procedures Aneurisma aórtico; Implantación de prótesis de vasos sanguíneos; Procedimientos endovasculares Aneurisma aòrtic; Implantació de pròtesis de vasos sanguinis; Procediments endovasculars Endovascular aneurysm repair (EVAR) is a minimally invasive treatment proposed as an alternative to open repair in patients with abdominal aortic aneurysms. EVAR consists in a stent-graft placement within the aorta in order to exclude the aneurysm from arterial circulation and reduce the risk of rupture. Knowledge of the various types of devices is mandatory because some stents/grafts are more frequently associated with complication…

Binding mode analysis of ABCA7 for the prediction of novel Alzheimer's disease therapeutics

2021

Graphical abstract

Giant hepatocellular adenoma as cause of severe abdominal pain: a case report

2007

Abstract The authors describe the case of a large hepatocellular adenoma diagnosed in a 30-year old woman who came to us complaining of acute pain in the upper abdominal quadrants. The patient had been taking an oral contraceptive pill for the last ten years. We present the clinical features, the diagnostic work-up and the treatment prescribed.

Median arcuate ligament syndrome, a rare case of chronic abdominal pain

2018

The median arcuate ligament syndrome (MALS) is a rare disease characterized by abdominal pain caused by the external compression of the celiac artery by the median arcuate ligament. Surgical treatment is indicated, but given the non-specific symptoms, these patients are often hospitalized in the Departments of Internal Medicine where the diagnosis may be unknown. We present a case of MALS admitted to our Internal Medicine Division. An abdominal ultrasound in a woman with longstanding abdominal pain showed elevated celiac artery velocities during forced expiration. Computed tomography angiography (CTA) of the abdomen showed stenosis of the origin of the celiac artery and confirmed the diagno…

A rare case of acute idiopathic colocolic intussusception in an adult patient

2020

Abstract Adult intussusception is a rare condition that is frequently associated with malignancy and requires surgical approach. Symptoms are often non-specific and of subacute or chronic character. Therefore, computerized tomography (CT) scan is the most commonly used modality for identifying adult intussusception. A 51-year-old female presented with a 1-day history of increasing abdominal pain. Abdominal ultrasound and CT scan revealed intussusception. Intra-operatively, colocolic intussusception was present and laparoscopically reduced. A lead point was found neither intra-operatively nor in post-operative ileocolonoscopy and resection of involved bowel segments was not necessary.

Abel transforms with low regularity with applications to X-ray tomography on spherically symmetric manifolds

2017

We study ray transforms on spherically symmetric manifolds with a piecewise $C^{1,1}$ metric. Assuming the Herglotz condition, the X-ray transform is injective on the space of $L^2$ functions on such manifolds. We also prove injectivity results for broken ray transforms (with and without periodicity) on such manifolds with a $C^{1,1}$ metric. To make these problems tractable in low regularity, we introduce and study a class of generalized Abel transforms and study their properties. This low regularity setting is relevant for geophysical applications.

Odontogenic abscess complicated by descending necrotizing mediastinitis: evidence of medical and dental malpractice

2016

Non-destructive automatic determination of aspect ratio and cross-sectional properties of fibres

2015

A novel method for computerised estimation of the aspect ratio distribution and various cross-sectional geometrical properties of fibres in short-fibre reinforced composites is proposed. The method, based on X-ray micro-computed tomography, is non-destructive and does not require user intervention. Based on results on specially fabricated model material, the accuracy and precision of the method seems adequate. The method is applied in analysing a manufacturing process of wood fibre reinforced thermoplastic composite. The results indicate a significant decrease of the aspect ratio of fibres during the processing steps. Finally, the feasibility of the method is assessed by estimating paramete…