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

Yıl 2018, Cilt: 39 Sayı: 1, 196 - 200, 16.03.2018

Cherif Kourtelı Fatima Benrachı

https://doi.org/10.17776/csj.359904

Öz

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.

Anahtar Kelimeler

Flattening Filter Free (FFF), 3D conformal radiotherapy (3D-CRT), Treatment planning, Dosimetric evaluation

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

Öz

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.

Anahtar Kelimeler

Düzleştirici Filtresiz (FFF), 3D konformal radyoterapi (3D-CRT), Tedavi planlaması, Dozimetrik değerlendirme

Kaynakça

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