Which statement about CT imaging is true?

Which statement about CT imaging is true?

• A. CT uses no ionizing radiation
• B. CT cannot generate axial images
• C. CT utilizes ionizing radiation
• D. CT is primarily used for functional imaging

Answer: (C)

CT imaging relies on ionizing radiation from X-ray beams. As these rays pass through the body, tissues attenuate the photons to varying degrees. Detectors capture the transmitted X-rays, and computers reconstruct the data into cross-sectional images, or slices. By default, these slices are axial, though they can be reformatted into coronal or sagittal views and rendered in 3D. This combination of attenuation measurement and reconstruction is why CT is excellent for detailed structural anatomy. The statement that CT uses no ionizing radiation is incorrect because the imaging mechanism depends on X-rays, which are ionizing. The claim that CT cannot generate axial images is incorrect because axial slices are the standard output, with the ability to reformat. The idea that CT is primarily used for functional imaging is also not accurate—CT is mainly a structural imaging modality, with some perfusion or enhancement studies possible, but not true functional imaging like PET or fMRI.

CT imaging relies on ionizing radiation from X-ray beams. As these rays pass through the body, tissues attenuate the photons to varying degrees. Detectors capture the transmitted X-rays, and computers reconstruct the data into cross-sectional images, or slices. By default, these slices are axial, though they can be reformatted into coronal or sagittal views and rendered in 3D. This combination of attenuation measurement and reconstruction is why CT is excellent for detailed structural anatomy.

The statement that CT uses no ionizing radiation is incorrect because the imaging mechanism depends on X-rays, which are ionizing. The claim that CT cannot generate axial images is incorrect because axial slices are the standard output, with the ability to reformat. The idea that CT is primarily used for functional imaging is also not accurate—CT is mainly a structural imaging modality, with some perfusion or enhancement studies possible, but not true functional imaging like PET or fMRI.