NEW METHOD FOR ESTIMATION OF FLUENCE COMPLEXITY IN IMRT FIELDS

English version České info

Intensity modulated radiation therapy (IMRT) planning and verification is a complex process but it could be simplified without compromising patient safety. One such way is suggested in our work. A new method for estimation of fluence complexity in IMRT fields is proposed. Unlike other previously published works, it is based on portal images calculated by the Portal Dose Calculation algorithm in Eclipse (version 8.6, Varian Medical Systems) in the plane of the EPID aS500 detector. Fluence complexity is given by the number and the amplitudes of dose gradients in these matrices. Our method is validated using a set of clinical plans where fluence has been smoothed manually so that each plan has a different level of complexity. Fluence complexity calculated with our tool is in accordance with the different levels of smoothing and correlates well with dose volume histogram parameters. Thus, it is possible to estimate plan complexity before carrying out the measurement, which could save time in the replanning and remeasuring process.

Keywords:
fluence complexity, IMRT verification, gamma analysis, radiotherapy

Autoři: Tereza Hanušová ^1,2; Vladimír Vondráček ^1,3; Klára Badraoui Čuprová ³; Ivana Horáková ⁴; Irena Koniarová ^1,4
Působiště autorů: Department of Dosimetry and Application of Ionizing Radiation, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Praha, Czech Republic ¹; Hospital Na Bulovce, Praha, Czech Republic ²; Proton Therapy Center Czech, Praha, Czech Republic ³; National Radiation Protection Institute, Praha, Czech Republic ⁴
Vyšlo v časopise: Lékař a technika - Clinician and Technology No. 1, 2016, 46, 29-32
Kategorie: Původní práce

Souhrn

Keywords:
fluence complexity, IMRT verification, gamma analysis, radiotherapy

Zdroje

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