Effective doses due to nuclear medicine procedures performed in Cluj-Napoca district (Romania) during 1998

Effective doses in diagnostic procedures performed in two nuclear medicine departments in Cluj-Napoca district are presented. Sex distribution of patients, percentage distribution of investigated organ and mean effective dose/patient as well as the annual collective effective doses for each department are calculated using ICRP model. The uses of I-131 in thyroid investigations and the high frequency of this type of examination (thyroid uptake and thyroid scintigraphy) lead to a high value of annual collective effective doses. More than 90% of annual collective dose of 397174 man.mSv in adult patients are due to the uses of sodium iodide (¹³¹I) in thyroid investigations. The main method proposed to reduce the doses in adult diagnostic examinations is to use ⁹⁹Te in thyroid scintigraphy