Final answer:
Multi-row detectors in CT scanners have different sizes along the z-direction, attenuation information can be added together to generate thicker slices, and all detector arrays may or may not be used.
Step-by-step explanation:
Multi-row detectors in CT scanners have several characteristics that are true.
Size of the detector arrays along the z-direction may be different: The detector arrays in a CT scanner can have different sizes along the z-direction, which allows for flexibility in imaging different parts of the body effectively.
The attenuation information from adjacent detector arrays may be added together to generate thicker slices: By adding the attenuation information from adjacent detector arrays, thicker slices can be generated, improving the image quality.
All of the detector arrays may or may not be used: Depending on the specific imaging requirements, all of the detector arrays in a multi-row detector CT scanner may or may not be used.