Tiroit Hastalıklarının Radyoiyot (I-131) Tedavisinde Absorbe ve Efektif Doz Hesaplamaları için Python Yazılım Kodu Geliştirilmesi

Abstract

Bu çalışmada, tiroidin benign hastalıklarından hipertiroidizmin tedavisinde tiroid bezini hedefleyen İyot-131 (I-131) radyoizotop tedavisi için doku ve organların absorbe ettikleri dozları ve efektif dozu hesaplamaya yönelik bir Python kodu geliştirilmiştir. Geliştirilen kod, biyokinetik verileri ve organlar arası etkileşimleri hesaba katacak şekilde tasarlanmıştır. Hesaplama sonuçları, MIRDcalc ve IDAC-Dose gibi mevcut dozimetri yazılımlarıyla karşılaştırılmıştır. Araştırmada, tiroid tedavisinde yetişkin hastalara uygulanan 5mCi, 10mCi, 15mCi ve 20mCi dozlarındaki I-131 radyoiyot uygulamalarının cinsiyete göre organ dozları ve efektif dozları hesaplanmıştır. Python kodu ile yapılan hesaplamalar, IDAC-Dose ile ortalama %1.8±0.9 hata marjıyla uyumlu sonuçlar vermiştir. Tiroid dokusu için Python kodu ile IDAC-Dose arasındaki doz sapması %0.7, MIRDcalc ile sapma %1.2 olarak belirlenmiştir. Cinsiyet farklılıkları incelendiğinde, kadınlarda karaciğer absorbsiyonu erkeklere göre %8.3 daha yüksek bulunmuştur. Efektif doz değerleri kadınlarda erkeklere göre daha yüksek kaydedilmiştir. 5-20mCi aralığında efektif doz-artış katsayısı 3.1-4.3 mSv/gCi olarak hesaplanmıştır. Hematopoetik sistem ve gonadlarda kadınlarda %8.3-14.1 daha yüksek absorbsiyon gözlenmiştir. Sonuç olarak, geliştirilen Python kodu, ICRP 103 kriterlerini karşılamakta ve hasta spesifik tedavi optimizasyonunda kullanılabilecek güvenilir bir alternatif olarak önerilmektedir.

Keywords

• I-131
• Radyoiyot
• Python Kod
• MIRDcalc
• IDAC-Dose

Development of Python Software Code for Absorbed and Effective Dose Calculations in Radioiodine (I-131) Treatment of Thyroid Diseases

Abstract

In this study, a Python code was developed to calculate the absorbed doses of tissues and organs and the effective dose for Iodine-131 (I-131) radioisotope therapy targeting the thyroid gland in the treatment of hyperthyroidism, a benign disease of the thyroid. The code has been designed to take into account biokinetic data and inter-organ interactions. The calculation results were then compared with those obtained from existing dosimetry software such as MIRDcalc and IDAC-Dose. The study involved the calculation of organ doses and effective doses of I-131 radioiodine applications to adult patients receiving thyroid treatment. The doses ranged from 5mCi to 20mCi, with the calculations conducted separately for male and female subjects. The Python code calculations yielded results that were consistent with those of IDAC-Dose, with an average error margin of 1.8 ± 0.9%. For thyroid tissue, the dose deviation between Python code and IDAC-Dose was 0.7%, while the deviation with MIRDcalc was 1.2%. A further analysis of gender differences revealed that liver absorption was 8.3% higher in females than in males. Effective dose values were found to be higher in females than males. In the range of 5-20mCi, the effective dose-increase coefficient was calculated as 3.1-4.3 mSv/gCi. Furthermore, an analysis of the haematopoietic system and gonads revealed a 8.3-14.1% higher absorption rate in females. In conclusion, the developed Python code meets the ICRP 103 criteria and is recommended as a reliable alternative for patient-specific treatment optimisation.

Keywords

• I-131
• Radyoiyot
• Python Kod
• MIRDcacl
• IDAC-Dose

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