Application Of 99m Tc Radioisotope In Diagnostic Procedures And Internal Radiation Dose Estimation

Abstract

At about 70% of nuclear medicine procedures have utilized 99m Tc in their clinical practices.This has lead 99m Tc becoming the most convenient radioisotope in nuclear medicine diagnostic. To estimate the internal radiation dose due to the administration of 99m Tc to the patients, only few documents from International Commission of Radiation Protection (ICRP) have been available.  However, the calculation usually has applied Caucasian data in Standard Reference Man as a model. The objective of this study was to review the application of 99m Tc in Indonesia and to compare the internal dose estimation for 99m Tc procedures by using Organ Level Internal Dose Assessment/ EXponential Modeling (OLINDA/EXM) software. The result of calculation was compared between Adult Caucasian model and Asian Reference Man. The result shows that 99m Tc has been well applied and developed for diagnostic procedures in Nuclear Medicine Department. Moreover, in most diagnostic procedures using 99m Tc in Indonesia, adult patients will receive effective dose about 1-15% higher than adult patient in foreign countries which apply the Caucasian model. Hence, to estimate the similar stochastic risk from the same procedure, the maximum value in recommended administered dose should be avoided and need to be evaluated.