Abstract

In radioiodine therapies, the most radiosensitive tissue in the body is the red bone marrow. The maximum iodine-131 activity is calculated through dosimetry to ensure that the blood-representing the dose-limiting organ, the bone marrow-receives a dose below 2 Gy during treatment. Dosimetry involves calculations based on measuring blood samples collected from the patient after administering approximately 74 MBq (2 mCi) of radioiodine, using a gamma counter.