Search results for "aging"
showing 10 items of 10496 documents
Synthesis of fluorine-18 labeled sulfonureas as ?-cell imaging agents
2001
Tolbutamide (1) and glyburide (7) are hypoglycemic drugs used to stimulate insulin secretion in type 2 diabetic patients. We have synthesized their fluorine-18 labeled analogs, 1-[(4-[ 18 F]fluorobenzenesulfonyl)]-3-butyl]urea (p-[ 18 F]fluorotolbutamide, 3a) and N-{4-[β-(2-[ 18 F]fluoroethoxybenzene carboxamido)ethyl]benzenesulfonyl)-N'-cyclohexylurea (2-[ 18 F]fluoroethoxyglyburide, 6a) as β-cell imaging agents. Compound 3a was synthesized via two approaches: One-step synthesis via nucleophilic substitution of p-nitrotolbutamide (2) with K[ 18 F]/Kryptofix 2.2.2 in either CH 3 CN or DMSO gave a complicated mixture; a two-step synthesis via preparation and reaction of 4-[ 18 F]fluorobenzen…
A boosting approach for prostate cancer detection using multi-parametric MRI
2015
International audience; Prostate cancer has been reported as the second most frequently diagnosed men cancers in the world. In the last decades, new imaging techniques based on MRI have been developed in order to improve the diagnosis task of radiologists. In practise, diagnosis can be affected by multiple factors reducing the chance to detect potential lesions. Computer-aided detection and computer-aided diagnosis have been designed to answer to these needs and provide help to radiologists in their daily duties. In this study, we proposed an automatic method to detect prostate cancer from a per voxel manner using 3T multi-parametric Magnetic Resonance Imaging (MRI) and a gradient boosting …
On the Use of XML in Medical Imaging Web-Based Applications
2016
The rapid growth of digital technology in medical fields over recent years has increased the need for applications able to manage patient medical records, imaging data, and chart information. Web-based applications are implemented with the purpose to link digital databases, storage and transmission protocols, management of large volumes of data and security concepts, allowing the possibility to read, analyze, and even diagnose remotely from the medical center where the information was acquired. The objective of this paper is to analyze the use of the Extensible Markup Language (XML) language in web-based applications that aid in diagnosis or treatment of patients, considering how this proto…
Towards data-driven medical imaging using natural language processing in patients with suspected urolithiasis.
2020
Abstract Objective The majority of radiological reports are still written as free text and lack structure. Further evaluation of free-text reports is difficult to achieve without a great deal of manual effort, and is not possible in everyday clinical practice. This study aims to automatically capture clinical information and positive hit rates from narrative radiological reports of suspected urolithiasis using natural language processing (NLP). Methods Narrative reports of low dose computed tomography (CT) of the retroperitoneum from April 2016 to July 2018 (n = 1714) were analyzed using NLP. These free-text reports were automatically structured based on RadLex concepts. Manual feedback was…
Analysis of in-silico body surface P-wave integral maps show important differences depending on the connections between coronary sinus and left atrium
2016
The electrical connections between the atrial coronary sinus (CS) and the left atrial (LA) myocardium have an effect on the overall atrial activation pattern and the P-wave morphology. In this study, we use our validated multi-scale 3D human atrial-torso model to elucidate which electro-anatomical configuration of connections between CS and LA more accurately reproduces a set of body surface P-wave integral maps (BSPiM) acquired in the clinic. We performed atrial biophysical simulations by pacing in distal and proximal LA sites. The corresponding in-silico BSPiM were then computed and compared with published clinical patterns obtained from patients. Important differences in BSPiM were obser…
Dynamic 4D Blood Flow Representation in the Aorta and Analysis from Cine-MRI in Patients
2007
International audience; Abstract: Natural evolution of aortic disease is characterized by a diameter increase that can result in aortic dissection or rupture. Currently the evaluation of risk of rupture or dissection is based on the size of the aorta. However, this parameter is not always relevant and it appears necessary to define new parameters. In this perspective, 3D velocity imaging acquired with ECG gated velocity-encoded cine-MRI allows the aortic blood flow study. As the acquired images are not directly usable, the present study proposes a 4D-representation Of aortic blood flow in order to optimize the visualization of the particularities of non-laminar flow within the aorta. Image …
Clinical Applications
2020
The study of the diagnostic accuracy of Infrared Thermal Imaging in the diagnosis of orthopaedic injuries in childhood has been motivated by the high incidence of these injuries throughout the world, being one of the most common reasons for urgent medical consultation. Diagnosis of musculoskeletal injuries usually involves radiography, but this exposes children without fractures to unnecessary ionising radiation. This chapter assesses whether infrared thermography could provide a viable alternative in cases of trauma. To evaluate the accuracy of this technique new thermographic variables have been added to those commonly analysed, such as the extent of the injury and the difference in the s…
Multimodality imaging strategies for the assessment of aortic stenosis: Viewpoint of the heart valve clinic international database (HAVEC) group
2016
International audience; Aortic stenosis is the most frequent valvular heart disease. In aortic stenosis, therapeutic decision essentially depends on symptomatic status, stenosis severity, and status of left ventricular systolic function. Surgical aortic valve replacement or transcatheter aortic valve implantation is the sole effective therapy in symptomatic patients with severe aortic stenosis, whereas the management of asymptomatic patients remains controversial and is mainly based on individual risk stratification. Imaging is fundamental for the initial diagnostic work-up, follow-up, and selection of the optimal timing and type of intervention. The present review provides specific recomme…
Walk the Line. The Surgical Highways to the Craniovertebral Junction in Endoscopic Approaches: A Historical Perspective
2018
Background We compiled a comprehensive literature review on the anatomic and clinical results of endoscopic approaches to the craniocervical junction (CVJ) to better contribute to identify the best strategy. Methods An updated literature review was performed in the PubMed, OVID, and Google Scholar medical databases, using the terms “Craniovertebral junction,” “Transoral approach,” “Transnasal approach,” “Transcervical approach,” “Endoscopic endonasal approach,” “Endoscopic transoral approach,” “Endoscopic transcervical approach.” Clinical series, anatomic studies, and comparative studies were reviewed. Results Pure endonasal and cervical endoscopic approaches still have some disadvantages, …
Role of Hemodynamic Forces in Unruptured Intracranial Aneurysms: An Overview of a Complex Scenario.
2017
Background An understanding of the natural history of unruptured intracranial aneurysms (IAs) has always played a critical role in presurgical or endovascular planning, to avoid possibly fatal events. Size, shape, morphology, and location are known risk factors for rupture of an aneurysm, but morphologic parameters alone may not be sufficient to perform proper rupture risk stratification. Methods We performed a systematic PubMed search and focused on hemodynamics forces that may influence aneurysmal initiation, growth, and rupture. Results We included 223 studies describing several hemodynamic parameters related to aneurysm natural history. In these studies, different modalities of aneurysm…