[Role of angio-MRI in the diagnosis of thoracic aortic diseases].

MRI is a promising method of studying aortic pathology because of its non-invasive nature and the possibility of obtaining morphological (on spin-echo sequences) and functional data (gradient echo with injection of contrast). Sequences sensitive to flow may be used to obtain angiographic-type images of the thoracic aorta. MRI is therefore the investigation of choice in the diagnosis and follow-up of dissections and aneurysms, both pre- and postoperatively. MRI allows differentiation between mural thrombosis and blood flow. The presence of a pleural effusion or of bleeding around the aorta is easily demonstrated. MRI also appears to be valuable in the assessment of aortic arch abnormalities because of its wide field of vision and its different spatial planes.