Magnetresonantsiülekannetes

Magnetresonantsiülekannetes, often referred to as magnetic resonance imaging (MRI) in English, is a non-invasive medical imaging technique that uses strong magnetic fields and radio waves to generate detailed images of organs and tissues within the body. It is based on the principle of nuclear magnetic resonance (NMR), where the nuclei of atoms, particularly hydrogen protons, align with a strong magnetic field. Radiofrequency pulses are then applied, causing these nuclei to absorb and then re-emit energy at specific frequencies. The emitted signals are detected by receiver coils and processed by a computer to create cross-sectional images.

Unlike X-ray based imaging, MRI does not use ionizing radiation, making it a safer option for repeated examinations and for sensitive populations. The contrast in MRI images arises from differences in the relaxation times of protons in various tissues. These relaxation times are influenced by the molecular environment and can be manipulated by adjusting imaging parameters, allowing for differentiation between different tissue types, such as muscle, fat, and fluid.

MRI is widely used to diagnose a broad range of conditions, including tumors, neurological disorders, cardiovascular diseases, and injuries to bones and joints. It excels at visualizing soft tissues, which are often poorly depicted by other imaging modalities. The technique can also be used for functional imaging, such as functional MRI (fMRI), which maps brain activity by detecting changes in blood flow. While highly effective, MRI examinations can be time-consuming, and the strong magnetic field means that patients with certain metallic implants cannot undergo the procedure.