Which statement correctly pairs PET with its primary measurement?

Which statement correctly pairs PET with its primary measurement?

• A. PET measures brain metabolism
• B. PET measures brain structure
• C. PET measures brain activity
• D. PET measures white matter integrity

Answer: (A)

PET primarily measures metabolic activity in the brain by using radiotracers such as fluorodeoxyglucose (FDG) that mimic glucose and are taken up by metabolically active cells. The amount of tracer that accumulates in a region reflects how much energy that brain tissue is using, giving a map of metabolic demand and function. This is different from measuring brain structure or anatomy, which is what structural MRI or CT do, and from directly recording electrical activity (like EEG) or the diffusion properties that reveal white matter integrity (as seen with diffusion MRI). So, the statement that PET measures brain metabolism best captures what this imaging modality is designed to reveal.

PET primarily measures metabolic activity in the brain by using radiotracers such as fluorodeoxyglucose (FDG) that mimic glucose and are taken up by metabolically active cells. The amount of tracer that accumulates in a region reflects how much energy that brain tissue is using, giving a map of metabolic demand and function. This is different from measuring brain structure or anatomy, which is what structural MRI or CT do, and from directly recording electrical activity (like EEG) or the diffusion properties that reveal white matter integrity (as seen with diffusion MRI). So, the statement that PET measures brain metabolism best captures what this imaging modality is designed to reveal.