Quantitative studies of bone with the use of F-18-fluoride and Tc-99m-methylene diphosphonate

This article discusses methods for quantifying bone turnover based on trace r kinetic studies of the short-lived radiopharmaceuticals Tc-99m-MDP and F- 18-fluoride. Measurements of skeletal clearance obtained by using these tra cers reflect the combined effects of skeletal blood flow and osteoblastic a ctivity. The pharmacokinetics of each tracer is described, together with so me of the quantitative tests of skeletal function that have been described in the literature. The physiologic interpretation of quantitative measureme nts of bone obtained with the use of short half-life radionuclides is discu ssed, and the advantages and limitations of Tc-99m-MDP and F-18-fluoride ar e compared and contrasted. Currently, F-18-fluoride dynamic positron emissi on tomography (PET) is the technique of choice for physiologically precise quantitative studies of bone. However, comparable data could probably be ob tained by using Tc-99m-MDP if methods for single photon emission computed t omography (SPECT) quantitation were improved. Copyright a 2001 by W.B. Saunders Company.