Serkan GÜRGÜL, Gülhan Güler AVCI, Tuğba GÜL, Serdar Savaş GÜL, Güner İpek KABALAY ARSLAN, Yasin ÇOBAN, Adil MERİH

CT parameter change and radiation dose effect for metastatic patients treated with palliative radiotherapy

Amaç: Bu çalışmanın amacı kemik ve diğer organ metastazı bulunan ve palyatif radyoterapi uygulanan hastalarda görüntüleme esnasında radyasyon dozunu azaltma yöntemlerini ortaya koymaktır. Metastazı bulunan hastalarda üç boyutlu (3D) konformal radyoterapi planlama aşamasında, ilgili bölgenin Bilgisayarlı tomografi (BT) ile tomografik görüntülemesi yapılmaktadır. BT çekimi için kullanılan parametrelerde değişiklik yapılarak, görüntüleme aşamasında radyasyon dozunun ne kadar azaltılabileceği araştırıldı. Yöntem: Radyasyon Onkolojisi bölümünde tedavi edilen metastazı olan 27 hasta (16E, 11K, yaş ortalaması 65.2 yıl ± 11.9) çalışmaya dahil edildi. 27 hastaya 30 palyatif radyoterapi uygulandı. Radyoterapi planlaması için yapılan 1. BT çekimde 72 mili-amper-saniye (mAs) ve 130 kilo-volt-pik (kVp) olan standart BT dozu 2. Çekimde 30mAs and 130kVp olacak şekilde değiştirildi. Bulgular: Planlama BT çekiminde yapılan değişiklik sonucunda radyasyon dozu %62.68±0.02 oranında azaltıldı (p

Original Research March 2018, Volume: 40, Number: 1 Cumhuriyet Medical Journal 762-767

Objective: The aim of the present study was to determine the methods to reduce the radiation dose during imaging carried out for patients with bone or other organ metastases who were treated with palliative radiotherapy. In planning stages of treatment for these patients, tomographic imaging with computed tomography (CT) is performed on affected area using three-dimensional (3D) conformal radiotherapy. To what level the radiation dose could be lowered in imaging was investigated via changing the parameters used in CT scanning. Method: Twenty seven patients with metastases treated in the Radiation Oncology department (16M, 11F, mean age 65.2 ± 11.9 years) were included in the study. These patients underwent a total of 30 palliative radiotherapy treatments. Standard CT dose of 72 milli-ampere-second (mAs) and 130 peak kilo voltage (kVp) in CT 1 scanning carried out for radiotherapy planning was lowered to 30mAs and 130kVp in CT 2 scanning. Results: Radiation dose was reduced by 62.68% ± 0.02 percent as a result of changes made in planning CT scan (p

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