Test Overview
Positron emission tomography (PET) is a test that uses a special
type of camera and a
tracer (radioactive chemical) to look at organs in the
body.
During the test, the tracer liquid is put into a vein (intravenous,
or
IV) in your arm. The tracer moves through your body,
where much of it collects in the specific organ or tissue. The tracer gives off
tiny positively charged particles (positrons). The camera records the positrons
and turns the recording into pictures on a computer.
PET scan pictures do not show as much detail as
computed tomography (CT) scans or
magnetic resonance imaging (MRI) because the pictures
show only the location of the tracer. The PET picture may be matched with those
from a CT scan to get more detailed information about where the tracer is
located.
A PET scan is often used to find cancer, to check blood flow, or to
see how organs are working.
See pictures of a
PET
scanner
and
PET scans
of the brain
.