NÜKLEER TIP UYGULAMALARINDA İNTERNAL DOZİMETRİ METODLARININ DEĞERLENDİRİLMESİ

Nükleer tıp uygulamalarında tanı ve tedavi amaçlı birçok radyonüklid kullanılır. Vücuttaki farklı organlar tarafından soğurulan radyasyon dozunun bilinmesi bu uygulamaların risklerinin ve yararlarının değerlendirilebilmesi açısından oldukça önemlidir. İnternal dozimetri vücut içindeki radyonüklidler ile dokuda depo edilen radyasyon enerjisinin uzaysal ve zamansal dağılımı ve miktarının belirlenmesi ile ilgilenir. Nükleer tıpta tiroid kanseri ve hipertiroidi tedavisinde yaygın kullanımı olan I-31 radyoizotopunun yanında, son yıllarda hepatosellüler karsinoma ve nöroendokrin tümör tedavisinde rutin uygulamaya giren Lu-177 ve Y-90 radyoizotopları da başarı ile uygulanmaktadır. Risk değerlendirilmesi açısından, organ doz hesapları Medikal İnternal Radyasyon Dozimetri (MIRD) tarafından belirlenen standart uygulamanın yanısıra, hastaya spesifik olarak kinetik ve anatomik parametrelerin değerlendirilmesi açısından önemlidir. Bu çalışmada internal dozimetri hesaplarında kullanılan metotlar ele alınmış, bu metodlarda farklı yaş ve cinsiyetlerdeki bireyleri temsil eden uygun modeller, matematiksel formulasyonlar ile açıklanmıştır

Anahtar Kelimeler:

İnternal dozimetri, MIRD metodu, radyasyon dozu

Evaluation of Internal Dosimetry Methods in Nuclear Medicine Applications

Many radionuclides are used for diagnostic and therapeutic in nuclear medicine applications. The knowledge of radiation dose absorbed by different organs in the body is critical to evaluate known risks and benefits of these applications. Internal dosimetry deals with the determination of the amount and the spatial and temporal distribution of radiation energy deposited in tissue by radionuclides within the body. Widely used in nuclear medicine in the treatment of thyroid cancer and hyperthyroidism radioisotope I-131, as well as routine practice in recent years into the treatment of hepatocellular carcinoma and neuroendocrine tumor Lu-177 and Y-90 also successfully applied to radioisotopes. In terms of risk assessment, the organ dose calculations Medical Internal Radiation Dosimetry (MIRD), as well as the application of the standard set by the patient-specific parameters in the evaluation of kinetics and anatomy is important. The methods used internal dosimetry calculations in this study are considered and the appropriate models representing individuals of different ages and regardless of gender are described with mathematical formulations.

Keywords:

Internal dosimetry, MIRD method, radiation dose,

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