Düzleştirici Filtresiz Foton Kirişlerin (FFF) 3D Konformal Radyoterapide Dozimetrik Etkilerinin Değerlendirilmesi

Düzleştirici Filtre Serbest (FFF) foton ışınları, radyoterapi klinik pratiğinde sıklıkla kullanılmaktadır. Bu çalışmada, 6 ve 10 MV foton enerjileri ve 3D konformal radyoterapi tekniği (3D-CRT) kullanılarak üç kanser bölgesi içeren üç hastanın tedavi planları için standart düzleştirilmiş kirişlere (FB) kıyasla FFF ışınlarının dozimetrik kalitesini analiz etmeyi amaçladık. Planlanan hedef hacim dozları (PTV'ler) ve risk altındaki organlar (OAR'ler) karşılaştırıldı. Doz-hacim histogram eğrileri analizi, FFF ve FB planları arasında PTV için ortalama doz ve ortalama doz arasında anlamlı bir fark bulunmadığını, OAR'ın hafif farklılıklar olduğunu göstermektedir. Böylece FFF foton ışını, standart düz kiriş olarak karşılaştırılabilir dozimetrik kaliteye ulaşmıştır

Evaluation of dosimetric impact of Flattening Filter-Free(FFF) Photon Beams in 3D conformal radiotherapy

Flattening Filter Free (FFF) photon beams have been frequently used in radiotherapy clinical practice. This study aimed to analyze the dosimetric quality of the FFF beams, as compared to the standard flattened beams (FB) for plans of treatment of three patients involving three cancer sites using the 6 and 10 MV photon energies and the 3D conformal radiotherapy technique (3D-CRT). The doses to the planning target volumes (PTVs) and organs at risk (OARs) were compared. The dose-volume histogram curves analysis show that no significant differences between FFF and FB plans were found in the coverage and mean dose for the PTV, the OAR revealed slight differences. So the FFF photon beam achieved comparable dosimetric quality as the standard flat beam

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