A PET scan is a type of imaging that can show what’s happening in your body. Learn why you might need one, what makes it different from other types of imaging, how to get ready, and what to expect.

A positron emission tomography (PET) scan is an imaging test that uses a special dye with radioactive tracers. Learn why it’s performed and how to prepare.

A brain scan showed CTE in ex-NFL player Fred McNeill before he died Second-year linebacker Fred McNeill is shown speaking at the Vikings training camp in Mankato, Minnesota on Aug. 19, 1975. AP file ...