Effective Half-Life of 131I of Whole-body and Individual Organs for Thyroidectomy Patient Using Scintigraphic Images of γ-camera

A 35-year-old male patient had undergone near-total thyroidectomy was selected for re-estimating T(subscript eff) Effective half-life (T (subscript eff)) of 131I of whole-body and individual organs was evaluated by in-vivo scintigraphic medical imaging with a γ-camera. Post-treatment whole-body scans (WBS) were subsequently performed from day 2 to day 8 after administration of 1.1 GBq of 131I. Pixels of scintigraphic images were obtained from bladder, salivary gland, stomach, testes, thigh, thyroid, and whole-body during 8-day intervals. T(subscript eff) of these organs could be derived using weighting factor intensification methodology. T(subscript eff) ranged from 0.99 to 2.83 days in the whole body as well as individual organs. Our results indicate that T(subscript eff) of the whole body of our thyriodetomy patient was similar to that of those who undergo complete ablation but quite different from normal adults, as reported for ICRP 30. In this study, we established a protocol for evaluating T(subscript eff) with clear scintigraphic images with a γ-camera. Our findings are important as establishing a protocol for re-estimating T(subscript eff) in the whole body, thyroid and some organs of interest.