甲狀腺全切除病人的碘-131體內動力學研究

Clinical Study of I-131 Biokinetic Model for Total (near) Thyroidectomy Patients

黃兆駿(CHAO-CHUN HUANG)

指導教授 ： 潘榕光

中臺科技大學/健康科學院/醫學影像暨放射科學系暨研究所/碩士(2018年)

摘要

目的：體內動力學模型是一用來描述人體攝入特定放射性物質後，放射性物質在人體內的分佈路徑、強度、循環以及排泄的情形。國際放射防護委員會(International Commission on Radiological Protection, ICRP)在其出版的30號報告，提出了碘的體內動力學模型。然而，模型的數據來源是標準健康受試者，是否能直接應用在甲狀腺全切除的甲狀腺癌患者仍有待評估。本研究針對四位甲狀腺已全切除並即將接受碘-131消融(Ablation)治療之患者進行體內動力學研究。
材料與方法：四位受試者皆已接受甲狀腺全切除術並即將進行碘-131 30mCi消融治療。受試者須分別於服藥後之1、4、24、48、72、168小時，接受全身掃描。影像經初步分析取得隔室各時間點之計數值後，再使用MATLAB程式進行試算及擬合。
結果：胃、體液+全身和甲狀腺的平均碘生物半衰期分別為0.0177、0.4375、3.125天；平均路徑強度I23(體液至甲狀腺)、I25(體液至排泄)分別為0.34、0.66。
結論：加馬攝影機可精確的對患者體內放射性藥物的分佈及強度進行量測，使用MATLAB程式反覆試算及擬合病患實際量測數據，可求得與病患實際生理狀況最符合之生物半衰期。本研究結果顯示，四位甲狀腺全切除患者的胃、體液+全身和甲狀腺的平均碘生物半衰期，相較於ICRP模型所描述的生物半衰期為0.029天、0.25天、80天有顯著變化。

關鍵字

甲狀腺 ； 甲狀腺全切除術 ； 放射碘 ； 體內動力學 ； 消融

並列摘要

Objective: The biokinetic model is used to describe the distribution path, intensity, circulation, and excretion in the human body after intake specific radiopharmaceutical. The report No.30 of the International Commission on Radiological Protection provided recommendations for the biokinetic of I-131. However, the model suggested data are for standard healthy human and obviously not applicable to thyroid cancer patients undergone total thyroidectomy. Thus, this study investigated the biokinetic model of I-131 in four patients who had undergone thyroidectomy and given administration of I-131 for ablation.
Materials and Methods: Four patients undergoing thyroidectomy and are about to be treated with iodine 131 30mCi. Patients must undergo whole body scan, at 1, 4, 24, 48, 72, 168 hours after administration, respectively. Image acquisition use GE Infinia Hawkeye 4 SPECT / CT. After preliminary analysis of the image to obtain the count value at each time point of the compartment, the MATLAB program is used for trial calculation and fitting.
Result: The mean iodine biological half-life of stomach, body fluid + whole body and thyroid was 0.0177, 0.4375, 3.125 days, respectively; the average path strengths I23(body fluid to stomach) and I25(body fluid to excretion) were 0.34 and 0.66.
Conclusion: Gamma camera can accurately measure the distribution and intensity of radiopharmaceuticals in patients. Using MATLAB software to repeat the trial calculation and fitting the patient's actual measurement data, can obtain the biological half-life that best matches the actual physiological condition of patients. The results showed significant changes in the effective half-life of thyroid and body fluids compared with the ICRP model.

並列關鍵字

Thyroid ； Thyroidectomy ； Iodine ； Biokinetic ； Ablation

參考文獻

[1] Patrick, L. Iodine: deficiency and therapeutic considerations. Altern Med Rev. 2008 Jun;13(2):116-27.

[2] Guyton and Hall. Textbook of Medical Physiology - 12th Edition. Elsevier.com. 2011.

[3] Wyszomirska, A. Iodine-131 for therapy of thyroid diseases. Physical and biological basis. Nucl Med Rev Cent East Eur. 2012 Aug 28;15(2):120-3.

[4] Skugor, M. Thyroid Disorders: A Cleveland Clinic Guide. Cleveland Clinic Press, 2006;p.82.

[5] European Commission. Radiation Protection series publications: 97, Radiation Protection Following. Iodine 131 Therapy (Exposures due to Out Patients or Discharged in Patients). 1988.