Evaluation of 3D Magnetic Resonance Spirometry : Comparison to Spirometry in Healthy Subjects and Patients With Asthma and COPD

Spirometry is now the gold standard technique for assessing lung function in humans. From the shape of a flow-volume curve measured while the patient, trained by the practitioner, performs forced breaths, the forced vital capacity (FVC) and the forced expiratory volume in one second (FEV1) can be deduced and the pulmonologist is able to detect and characterize respiratory diseases as well as to evaluate current treatments. This technique is non-invasive and simple. It is widely available, robust, reproducible and sensitive to intervention. However, it requires proactive cooperation from the patient and only measures global pulmonary ventilation, without locoregional information.An innovative strategy and an original study framework have been developed in the BioMaps laboratory to establish local maps of flow-volume curves across the lung and to jointly analyze ventilatory function and mechanical behavior at any point in the lung: 3D magnetic resonance spirometry. As respiratory mechanics fundamentally supports ventilatory function, this technique should open a new avenue to non-invasively explore lung function while providing a better diagnosis of regional lung diseases.

Inclusion Criteria:Ability to understand the nature and objectives of the study and to appreciate the risks involvedAbility to stand in an MRI machine without moving in supine and prone positionsInformed and written consentFor healthy subjects:No known diagnosed lung disease such as respiratory failure, COPD, asthma or cancerNon-smokerFor asthmatic subjects:Asthma of varying degrees of severityNon-smoker For COPD subjectsCOPD with different degrees of severityExclusion Criteria:Refusal to sign consentAny pathology or condition (active tumor, pregnancy, breastfeeding) that the investigators believe may compromise the safety of the subject or the objectives of the studyPersons who have had a symptomatic Covid-19 infectionContraindication to performing an MRI examination (claustrophobia, metallic prosthesis, pacemaker, metallic prosthetic heart valve, cochlear implants, vascular clips, insulin pump)Contraindication to spirometry testing (acute myocardial infarction, severe systemic hypotension or hypertension, significant atrial/ventricular arrhythmia, uncompensated heart failure, uncontrolled pulmonary hypertension, pulmonary embolism, history of syncope, cerebral aneurysm, brain surgery (4 weeks), recent concussion, eye surgery (1 week), sinus or middle ear surgery, pneumothorax, thoracic or abdominal surgery (4 weeks)Contraindication to the administration of a short-acting bronchodilator (history of hypersensitivity to the active substance or to one of the excipients, history of intolerance to the product such as the occurrence of cough or bronchospasm after inhalation, pregnancy, thyrotoxicosis, coronary artery disease, hypertrophic obstructive cardiomyopathy, hypertension, tachyarrhythmia, diabetes, association with digitalis, MAO inhibitors, tricyclic antidepressants, known hypokalemia or hypokalemic drugs: diuretics, laxatives, steroids, xanthine).Non-membership in a social security systemProtected persons (guardianship, curatorship) For healthy subjects and asthmatic subjectsTobacco history of more than 5 packs/year