| Abstract [eng] |
The dissertation presents an overview of the possibilities of contrast unenhanced magnetic resonance imaging (MRI) sequences and magnetic resonance angiography with a contrast media for evaluating the aorta and segmental diameters, methods for determining pulse wave velocity in aorta, their advantages and disadvantages, practical application, comparison with ultrasound technique. The goal was to determine the practical application of MRI contrast unenhanced sequences in diagnosis of aortic diseases and to make up a protocol for this study. Data were analysed in population with primary arterial hypertension and healthy persons with tricuspid and bicuspid aortic valves. Following the EU ban on linear contrast media in 2017, contrast unenhanced MRI of aorta gets even more clinical significance. On the basis of our work results, we see real practical benefits and suggest for routine cases to use contrast unenhanced MRI in accordance with the described methodology to be used for evaluation of maximum diameters of aorta. Especially, when cardiovascular diseases in Lithuania and in the world are not decreasing and the ways are sought for the simplest and most economical, but reliable research for aortic pathological changes. It is recommended that the diameters of the bicuspid aortic valve should be evaluated in the images of the short axis of the valve in all imaging techniques, in order to avoid measurement inaccuracy due to congenital sinus asymmetry. We propose the use of non-contrast MRI technique to determine pulse wave velocity in the aortic arch as an alternative for the applanation tonometry. |
