Nuclear medicine uses radioisotopes to evaluate physiological activity of both normal body organs as well as of malignancy.
With a few exceptions such as the use of contrast xray, ct, us or MRI
for the most part study the anatomy and anatomical changes associated with diseases. Nuclear medicine studies physiological processes. This may involve study of contraction
of the heart
to evaluate for cardiac dysfunction, flow of cerebral spinal fluid to evaluate for potential obstruction, contraction of the gallbladder to find out why some has abdominal pain
after meals. It can also evaluate whether a tumor or growth exhibits certain aggressiveness by seeing how much sugar
it takes up comparing to normal tissues and whether that growth has spread elsewhere in the body.
Nuclear medicine can also be used to treat a few disease. This is particularly in thyroid diseases
131 can be used to ablate the thyroid gland and or some of the thyroid cancers.
There is a subset of nuclear medicine that uses molecular imaging
where a molecule is used to target a certain particle or cells in the organ or tumor.
You can also review the follow links for additional info, provided by the american college of radiology: