ABSTRACT
To understand the uptake of radioactive tracers into bone it is first necessary to understand the structure, composition, and metabolism within the bone. Bone is a living matrix consisting of living cells surrounded by an organic matrix which is impregnated with an inorganic crystalline matrix. The iron radionuclides have normally been considered to localize in the bone marrow when injected intravenously in the ionic form. However, there is a report in the literature which shows that iron, when injected as the ferrous salt, is taken up to some extent by the bone, as well as the bone marrow. The first anion which was employed for bone localization was the fluoride ion in the form of fluorine-18 fluoride. It is generally believed that the uptake of the alkaline earths, rare earths, ionic gallium, ionic lead, and fluoride, by the bone takes place on the hydroxyapatite crystals of the bone by the process of ion exchange.
