I-131 Radyoizotop Aktivitelerinin Nükleer Tıpta Kullanılan Organ Dozu Üzerine Etkisi
Hayatta radyasyona maruz kalmanın birçok yolu vardır. Özellikle tıbbi uygulamalar, şiddetli maruziyetin en önemli sebebidir. Tıbbi uygulamalarda Bilgisayarlı Tomografi (BT) taramaları ilk sırada yer alırken, nükleer tıp ikinci sırada yer almaktadır. Tabii ki, maruz kalan doku ve dolayısıyla organlar tarafından emilen doz, sağlığa yönelik risklerle doğru orantılıdır. Nükleer tıpta tedavi amaçlı vücuda yerleştirilen radyoizotoplar nedeniyle sadece tümörün bulunduğu organ ve/veya dokulara değil, çevredeki diğer organ ve dokular az miktarda olsa da doz absorbe eder. Bu çalışmada erişkin fantomların (erkek ve dişi) tiroid bezine yerleştirilen iyot radyoizotop I-131'in aktivitelerine göre tiroid bezi, timüs ve lenf bezlerinin aldığı dozlardaki değişim Monte Carlo-tabanlı NCINM kodu ile araştırılmıştır.
Effect of I-131 Radioisotope Activities on Organ Dose Used in Nuclear Medicine
There are many ways to be exposed to radiation in life. Medical applications, in particular, are the most important form of severe exposure. In medical applications, Computed Tomography (CT) scans are in the first place, while nuclear medicine is in the second place. Of course, the dose absorbed by the exposed tissue and therefore the organs is directly proportional to the risks to health. In nuclear medicine, due to the radioisotopes placed in the body for therapeutic purposes, some doses are not given only to the organ and/or tissues where the tumor is placed, but also to other surrounding organ and tissues. In this study, the change in the doses received by the thyroid gland, thymus, and lymph nodes according to the activities of the iodine radioisotope I-131 placed in the thyroid gland of adult phantoms (both male and female) were investigated with the Monte Carlo-based code.
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