Which imaging modality provides radiographic cross-sectional images using a small beam of radiation?

Which imaging modality provides radiographic cross-sectional images using a small beam of radiation?

• A. Ultrasound
• B. Magnetic Resonance Imaging
• C. Computed Tomography
• D. Mammography

Answer: (C)

Computed tomography is designed to produce radiographic cross-sectional images by using a rotating X-ray beam that is collimated into thin slices. Detectors capture the attenuated X-rays from many angles, and a computer reconstructs the data into axial cross-sections. This creates detailed internal slices that can be viewed individually or compiled into a 3D representation. Ultrasound uses sound waves, not ionizing radiation. MRI relies on magnetic fields and radiofrequency pulses, not X-rays. Mammography uses X-rays for breast imaging, typically as 2D projections (though tomosynthesis exists).

Computed tomography is designed to produce radiographic cross-sectional images by using a rotating X-ray beam that is collimated into thin slices. Detectors capture the attenuated X-rays from many angles, and a computer reconstructs the data into axial cross-sections. This creates detailed internal slices that can be viewed individually or compiled into a 3D representation.

Ultrasound uses sound waves, not ionizing radiation. MRI relies on magnetic fields and radiofrequency pulses, not X-rays. Mammography uses X-rays for breast imaging, typically as 2D projections (though tomosynthesis exists).