Which imaging technique measures blood flow through radioactive decay?

The correct answer is the PET scan, which stands for Positron Emission Tomography. This imaging technique is unique in its ability to visualize metabolic processes in the body by detecting the radiation emitted from radioactive isotopes. In a PET scan, a radioactive tracer is introduced into the body, typically through an injection. This tracer is often a glucose analog, which gets taken up by cells, especially in areas of high metabolic activity, such as tumors or active brain regions.

As the radioactive isotopes decay, they emit positrons, which interact with electrons in the body, resulting in the emission of gamma rays. These gamma rays are then detected by the PET scanner to create detailed images of blood flow and metabolic activity in various tissues. This makes PET scanning particularly valuable in identifying cancer, monitoring brain activity, and assessing various neurological conditions.

The other imaging techniques do not utilize radioactive decay to measure blood flow. MRI, or Magnetic Resonance Imaging, uses strong magnetic fields and radio waves to generate images of the body’s soft tissues but does not involve radioactive substances. A CT scan, or Computed Tomography scan, combines X-ray images taken from different angles to create cross-sectional images of the body without measuring metabolic activity. EEG, or Electroencephalography