Kamil Erkan ÖZGEN, Şükran ESKİCİ ÖZTEP, Mehmet Bahadır ÇELİK, Eda Bengi YILMAZ, Mehmet KABADAYI

Comparison of patient specific quality assurance tests done with using different dosimetric systems for intensity modulated radiotherapy treatment plans

Intensity modulated radiotherapy is the developed technique of 3 dimensional conformal radiation therapy. In this method, irradiated fields can be seperated into many subfields that are called segments. Each segments’ radiation dose can be adjusted. Intensity modulated radiotherapy plans have complex segments and high gradient dose regions. Therefore, quality assurance of intensity modulated radiotherapy plans is very important. The aim of this study is to perform quality assurance tests of intensity modulated radiotherapy plans by using different dosimetric systems and compare of results. Intensity modulated radiotherapy treatment plans of thirty patients’ quality assurance were tested using Matrixx and Delta4. Then, gamma pass rates that were determined as a result of the gamma analysis done using gamma pass-fail criteria that had values of different dose difference and distance to agreement. In our study, the differences between the mean values of gamma pass rates determined before were statistically examined and there was significant difference between two dosimetric systems.

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