Search results for "Imagerie médicale"
showing 7 items of 7 documents
Development of functionalizable azaBODIPYs for the conception of theranostic agents and bimodal probes for imaging uses
2020
The in vivo use of optical imaging is still limited by the lack of near infrared emitting probes. This thesis work focuses on the optimization and valorization of a water-soluble fluorescent platform whose optical properties enable an in vivo use. Two distinct applications were investigated for this WazaBY (Water-soluble azaBODIPY) platform: use as a PET (or SPECT) / optical bimodal probe, and as a theranostic agent. Concerning the first project, we were able to develop a targetted SPECT/optical bimodal probe, which was radiometallated with indium 111. Using xenografted murine models, we were able to show a clear accumulation of the probe in the tumor 24 hours after injection. Moreover, the…
ESGAR consensus statement on liver MR imaging and clinical use of liver-specific contrast agents
2016
Objectives: To develop a consensus and provide updated recommendations on liver MR imaging and the clinical use of liver-specific contrast agents. Methods: The European Society of Gastrointestinal and Abdominal Radiology (ESGAR) formed a multinational European panel of experts, selected on the basis of a literature review and their leadership in the field of liver MR imaging. A modified Delphi process was adopted to draft a list of statements. Descriptive and Cronbach’s statistics were used to rate levels of agreement and internal reliability of the consensus. Results: Three Delphi rounds were conducted and 76 statements composed on MR technique (n = 17), clinical application of liver-speci…
Segmentation automatique et analyse de forme d'hippocampes humains dans l'étude de la maladie d'Alzheimer
2011
The aim of this thesis is to investigate the shape change in hippocampus due to the atrophy in Alzheimer’s disease (AD). To this end, specific algorithms and methodologies were developed to segment the hippocampus from structural magnetic resonance (MR) images and model variations in its shape. We use a multi-atlas based segmentation propagation approach for the segmentation of hippocampus which has been shown to obtain accurate parcellation of brain structures. We developed a supervised method to build a population specific atlas database, by propagating the parcellations from a smaller generic atlas database. Well segmented images are inspected and added to the set of atlases, such that t…
Conceptual graph operations for formal visual reasoning in the medical domain
2014
International audience; Objective - Conceptual graphs (CGs) are used to represent clinical guidelines because they support visual reasoning with a logical background, making them a potentially valuable representation for guidelines.Materials and methods - Conceptual graph formalism has an essential and basic component: a formal vocabulary that drives all of the other mechanisms, notably specialization and projection. The graph's theoretical operations, such as projection, rules, derivation, constraints, probabilities and uncertainty, support diagrammatic reasoning.Results - A conceptual graph's graphical user interface includes a multilingual vocabulary management, some query and decision-m…
Dispositif virtuel d'aide à la chirurgie de l'épaule
2008
The goal of this research is to design a virtual reality prototype to assit an orthopedic surgeon during the replacement of the glenohumeral joint by prosthesis. This system aims to optimize the movements of prosthesized shoulder joint from a choice of various scenarios of pose. These works encompasses several topics such as : orthopedic surgery, image analysis, computer graphics and virtual reality. The chosen process includes a phase of modelling of the bony part of the articulation by simple geometric forms, this model is parameterized from radios or CT scans ; a phase of simulation of the movements of healthy glenohumeral joint ; nally the phase of simulation of cutting and drilling wit…
Etude des propriétés de coordination de nouveaux ligands macrocycliques vis-à-vis de cations métalliques en vue de l'utilisation de leurs complexes p…
2011
Noninvasive medical imaging techniques such as single-photon emission computed tomography (SPECT) or positron emission tomography (PET), are valuable tools for the development and validation of new therapeutic molecules. That approach requires the conjugation of a radioactive source emitting either y-rays or positrons with a biological tracer (e.g. DOTATOC). Among the potentially useful radionuclides available, 111In3+ (SPECT), 64Cu2+, and 68Ga3+ (PET) have attracted increasing attention over the last years for medical applications. To minimize the in vivo release of the radioactive cation by transmetalation or transchelation with biological ligands, it is essential to trap selectively the …
Frontal Electroencephalogram Alpha Asymmetry during Mental Stress Related to Workplace Noise
2021
This study aims to investigate the effects of workplace noise on neural activity and alpha asymmetries of the prefrontal cortex (PFC) during mental stress conditions. Workplace noise exposure is a pervasive environmental pollutant and is negatively linked to cognitive effects and selective attention. Generally, the stress theory is assumed to underlie the impact of noise on health. Evidence for the impacts of workplace noise on mental stress is lacking. Fifteen healthy volunteer subjects performed the Montreal imaging stress task in quiet and noisy workplaces while their brain activity was recorded using electroencephalography. The salivary alpha-amylase (sAA) was measured before and immedi…