Which imaging modality uses strong magnets and radio waves to view three-dimensional images of the body?

Which imaging modality uses strong magnets and radio waves to view three-dimensional images of the body?

• A. Magnetic resonance imaging
• B. X-ray
• C. CT scan
• D. Ultrasound

Answer: (A)

The concept being tested is imaging that uses a strong magnetic field and radio waves to create detailed three‑dimensional body images. Magnetic resonance imaging does this by aligning the body's hydrogen nuclei with a powerful magnet, then using radiofrequency pulses to disturb that alignment. As the nuclei return to their resting state, they emit signals that are encoded to form highly detailed cross‑sections and 3D volumes, with great contrast between soft tissues. This capability to produce multi‑planar and three‑dimensional reconstructions is a hallmark of MRI. X‑ray and CT rely on ionizing radiation from X‑rays to generate images, and while CT can provide 3D reconstructions, it still uses X‑ray attenuation rather than magnets. Ultrasound uses sound waves and echoes, not magnets or radio waves. Hence the modality that uses strong magnets and radio waves to view three‑dimensional images is magnetic resonance imaging.

The concept being tested is imaging that uses a strong magnetic field and radio waves to create detailed three‑dimensional body images. Magnetic resonance imaging does this by aligning the body's hydrogen nuclei with a powerful magnet, then using radiofrequency pulses to disturb that alignment. As the nuclei return to their resting state, they emit signals that are encoded to form highly detailed cross‑sections and 3D volumes, with great contrast between soft tissues. This capability to produce multi‑planar and three‑dimensional reconstructions is a hallmark of MRI.

X‑ray and CT rely on ionizing radiation from X‑rays to generate images, and while CT can provide 3D reconstructions, it still uses X‑ray attenuation rather than magnets. Ultrasound uses sound waves and echoes, not magnets or radio waves. Hence the modality that uses strong magnets and radio waves to view three‑dimensional images is magnetic resonance imaging.