What type of imaging technique uses magnetism and radio waves?

Magnetic Resonance Imaging (MRI) is the imaging technique that utilizes magnetism and radio waves to create detailed images of the body’s internal structures. MRI employs strong magnetic fields to align the protons in hydrogen atoms, which are abundant in the human body, especially in water and fat. Once the protons are aligned, radiofrequency pulses are applied, causing the protons to emit signals as they return to their original state. These signals are then translated into images by the MRI system, allowing for high-resolution visualization of soft tissues, organs, and other structures without the use of ionizing radiation, making it a safe option for various diagnostic purposes.

In contrast, computed tomography (CT) uses X-rays to take cross-sectional images of the body, and X-ray imaging itself directly employs X-ray radiation to visualize hard tissues like bones. Ultrasound imaging uses sound waves to produce images and is often employed in obstetrics and other applications but does not involve magnetism or radio waves. This distinctive use of magnetic fields and radiofrequency in MRI distinguishes it from the other imaging techniques listed.