本研究探討藉γ-攝影機進行放射性碘（碘-131）所形成的醫學影像來重新估算全身及甲狀腺有效半衰期（T（下標 eff）），一位35歲男性甲狀腺癌患者經全部或近乎全切除手術後，攝入1.1GBq碘-131的第2天至8天進行全身掃描（whole-body scans WBS）。醫學影像行成的膀胱、唾液腺、胃、睪丸、大腿內側及甲狀腺之像素可由8天中擷取，T（下標 eff）值並以加權平均法重新估算。結果顯示上列器官的T（下標 eff）為由0.99至2.83天。此值與文獻上全切除患者相符合但與國際放射防護委員會（ICRP）30號報告的正常成人極大不同，本研究是藉γ-攝影機所形成全身醫學影像來清楚地重新估算器官及甲狀腺有效半衰期，此方法是一連串重新估算之起步，此發現應具有相當顯著性的意義。
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.
