Which imaging modality is described as using magnetic fields and radio waves to generate images of soft tissues?

Which imaging modality is described as using magnetic fields and radio waves to generate images of soft tissues?

• A. Radiography
• B. CT Scan
• C. MRI (magnetic resonance imaging)
• D. Ultrasound

Answer: (C)

Magnetic resonance imaging uses magnetic fields and radio waves to create images of soft tissues. In MRI, a strong external magnetic field aligns the hydrogen nuclei (protons) in the body's water and fat. A radiofrequency pulse then tips these protons away from alignment. When the pulse ends, the protons realign and emit signals that are detected by sensors and processed into images. Because different tissues have distinct relaxation properties, MRI provides excellent contrast between soft tissues like brain, spinal cord, muscles, and ligaments. It also avoids ionizing radiation, unlike X-ray or CT. Ultrasound relies on sound waves, so it produces a different type of image. This description matches MRI.

Magnetic resonance imaging uses magnetic fields and radio waves to create images of soft tissues. In MRI, a strong external magnetic field aligns the hydrogen nuclei (protons) in the body's water and fat. A radiofrequency pulse then tips these protons away from alignment. When the pulse ends, the protons realign and emit signals that are detected by sensors and processed into images. Because different tissues have distinct relaxation properties, MRI provides excellent contrast between soft tissues like brain, spinal cord, muscles, and ligaments. It also avoids ionizing radiation, unlike X-ray or CT. Ultrasound relies on sound waves, so it produces a different type of image. This description matches MRI.