What are the benefits of using technetium-99m for medical tracing instead of x-rays?

Funct. vs. anatomic. Nuclear medicine involves using internal irradiation in order to define function of various organ systems of body, . Some isotopes are injected iv, inhaled, and some ingested. Most diagnostic nuclear medicine procedures involve low doses of radiation. The isotopes of higher doses are used to treat thyroid diseases or cancer. Benefits are from diagnosis of abnormality that can be detected/ treated.