Tomography

The purpose of this study is to validate the clinical measurement performance of an investigational biometer. Subjects will undergo multiple measurements of the eye, and the agreement, repeatability, and reproducibility of corneal and epithelial thickness maps will be evaluated.

The goal of this clinical trial is to learn how night shift-induced sleep debt affects oculomotor patterns, attentional state, and diagnostic performance in emergency radiologists. The main questions it aims to answer are: * Does sleep debt from a night shift alter oculomotor parameters, as eyes movements (speed and amplitude), fixation duration, pupil size? * Does a night shift impact radiologists' diagnostic accuracy, attentional state, and perceived fatigue? Researchers will compare radiologists after a night shift (sleep-deprived) with the same radiologists after a night of rest (control) to see if fatigue-related changes affect both visual exploration strategies and diagnostic performance. Participants will: * Perform a guided saccade task assessed by eye tracking (primary endpoint), * Read thoracic CT scans (with and without pulmonary embolism cases) to assess diagnostic performance and visual exploration patterns, * Undergo EEG recording to measure attentional state, * Complete self-report questionnaires on sleepiness and fatigue.

Glomerular filtration rate (GFR), which is the main biomarker used in clinical practice to assess kidney function, is usually estimated from the serum concentration of endogenous markers such as creatinine and/or cystatin C. GFR estimation equations all share the disadvantage of imperfect accuracy due to non-GFR-related determinants of creatinine and cystatin C. When knowing the exact GFR value is necessary for clinical decision-making, measurement by clearance of an exogenous tracer is required. Various tracers are available, some of which are radioactive tracers (99mTc-DTPA and 51Cr-EDTA), while others are iodinated contrast agents (iohexol, iothalamate). GFR measurement procedures are time-consuming and require significant human resources (4 to 5 hours, or even 24 hours for plasma clearances at very low GFR values).Urinary clearance methods may be inaccurate in cases of inadequate voiding. Plasma clearance results may be inaccurate in cases of increased (overestimation) or decreased (underestimation) extracellular volume, low GFR (unless late sampling is performed), or glomerular hyperfiltration. Measuring tracers requires either warm labs for measuring radioactive markers or labs with HPLC (High Performance Liquid Chromatography) chains for iohexol, which are part of an external quality assurance program. The complexity and/or length of GFR measurement procedures, their cost, and laboratory constraints explain why measured GFR is underused in routine clinical practice. There is a critical need to develop GFR measurement methods that are simpler to implement, reliable across the entire GFR spectrum, and widely available. We have demonstrated that it is possible to measure GFR using 4-phase CT urography performed as part of the care of living kidney donor candidates (healthy individuals with normal GFR). The examination takes 10 minutes, requires no biological sampling, and is not subject to potential inaccuracies due to sodium overload or poor bladder emptying.

The MOBILE project is part of the dynamic European collaboration of the Human Brain Project (HBP). The overall aim of the project is to characterize brain structure and function in healthy subjects and patients with epilepsy, using a quantitative multimodal approach involving both neuroimaging (MRI, PET) and electrophysiology (EEG/MEG). The project is funded by the European HBP consortium, and the data acquired will ultimately be made available to the scientific community formed by this international collaboration. Several aspects of the project have already been initiated on the basis of extensions to previous authorizations, or as part of care activities. As part of this overall project, the present MOBILE-PET application concerns exclusively the performance of 18F-FDG PET (Positron Emission Tomography) imaging in the 30 healthy adult subjects in the protocol (aged 18 to 65, with inclusion parity for gender). This cerebral examination, performed at rest on a 45-minute 3D volume acquisition, enables quantitative measurement of the metabolic consumption of glucose underlying global synaptic activity, and to determine the associated connectivity. Around 1,500 examinations of this type are carried out each year in our department as part of care for patients with brain pathology, and over 10,000 for patients with cancer. This examination requires intravenous injection of a weakly radioactive tracer corresponding to a radiopharmaceutical which has been approved for marketing for over 20 years. We also carried out and finalized a similar project in 2007 on 60 healthy subjects, using a previous-generation PET camera (NCT00484523). The Nuclear Medicine Department holds clinical research authorizations for imaging in patients and healthy subjects (including early phase and first-in-man, although the present project does not fall into this research categarogy).