"Siemens ONCOR" tedavi cihazının küçük monitor unit değerlerinde ve küçük segment boyutlarında dozimetrik performansının değerlendirilmesi ve planlama sistemi ile uyumu
AMAÇ Siemens ONCOR Avant-Garde lineer hızlandırıcısının“intensity modulated radiation therapy=IMRT” uygulamalarındaki performansını değerlendirmek için, küçük monitor unit (MU) değerlerindeki doz linearitesi, doz doğruluğu ve küçük alan boyutlu segmentlerdeki doz değerlerinin doğruluğu araştırıldı.GEREÇ VE YÖNTEM Cihazın küçük MU değerlerinde doz linearitesi ve doğruluğu için 0.6 cc “Farmer” iyon odası ve 47 tane diod içeren PTWLA48 lineer dedekt örü kullanıldı. Küçük alanlarda doz doğrulaması ise, PTW Si Diod dedektörlerle ölçülen doz değerleri ile planlama sisteminde elde edilen doz değerleri karşılaştırılarak yapıldı.BULGULAR Küçük MU değerinde doz linearitesi için alınan ölçümlerde
Evaluation of dosimetric performance of "Siemens ONCOR" linear accelerator with small monitor unit values and small segment sizes and consistency with treatment planning system
OBJECTIVES The aim of our study was to evaluate the performance of the “Siemens ONCOR Avant-Garde” linear accelerator under intensity modulated radiation therapy (IMRT) conditions. The beam stability for small monitor units in terms of dose linearity, inter-segment variations and profiles was investigated. Validation of doses at small size segments was done to compare with measurement and calculation dose values.METHODS Measurements of linearity and beam stability with small monitor units were done using 0.6 cc “Farmer” ion chamber and PTW-LA48 linear detector with 47 diodes. Validation of doses for small segment sizes was done for comparison of the values obtained with the PTW Si diode detector and the calculated values on the planning system.RESULTS Dose linearity of small monitor units was found to be 2 monitor unit setting were measured at an acceptable value, 3%,
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- ISSN: 1300-7467
- Başlangıç: 2015
- Yayıncı: Ali Cangül
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