Medicinski vjesnik, Vol. 31 No. (1-4), 1999.
Professional paper
Principles of magnetic resonance imaging
Jasminka Brnjas-Kraljević
Maja Balarin
Sanja Dolanski-Babić
Abstract
Nuclear magnetic resonance (NMR) is a phenomenon of absorption and reemission of radio frequency (RF) electromagnetic energy by certain nuclei placed within strong magnetic fields. The NMR frequency, hence the energy of interaction, of the detected electromagnetic radiation from a given nuclear type is dependent critically on the magnetic and molecular environment of the stimulated nuclei. Therefore the NMR parameters bear the structural information on molecular level. The energy exchange mechanisms (relaxation) take place on a microscopic scale and the information about local dynamic properties is acquired by measuring relaxation times. In imaging by NMR, local differences in NMR parameters are used to obtain anatomic data. Magnetic field gradients are used to obtain spatial information. The advantages of MRI include the ability to obtain images in multiple orientations, absence of ionizing radiation and potential to obtain structural and dynamical information about the investigated system.
Keywords
Hrčak ID:
191962
URI
Publication date:
1.12.1999.
Visits: 2.290 *