Complexity metric based on fraction of penumbra dose - initial study

9th International Conference on 3D Radiation Dosimetry

Bäck, A.^1 ; Nordström, F.^1 ; Gustafsson, M.^1 ; Götstedt, J.^2 ; Karlsson Hauer, A.^1

Department of Therapeutic Radiation Physics, Sahlgrenska University Hospital, Göteborg, Sweden^1

Department of Radiation Physics, University of Gothenburg, Göteborg, Sweden^2

关键词: Complexity metrics;    Measurement-based;    Multileaf collimators;    R value;    Spatially resolved;    Three-dimensional conformal radiotherapy;    Treatment plans;    Volumetric modulated arc therapy;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/847/1/012002/pdf
DOI  :  10.1088/1742-6596/847/1/012002

来源: IOP

【 摘 要 】

Volumetric modulated arc therapy improve radiotherapy outcome for many patients compared to conventional three dimensional conformal radiotherapy but require a more extensive, most often measurement based, quality assurance. Multi leaf collimator (MLC) aperture-based complexity metrics have been suggested to be used to distinguish complex treatment plans unsuitable for treatment without time consuming measurements. This study introduce a spatially resolved complexity score that correlate to the fraction of penumbra dose and will give information on the spatial distribution and the clinical relevance of the calculated complexity. The complexity metric is described and an initial study on the correlation between the complexity score and the difference between measured and calculated dose for 30 MLC openings is presented. The result of an analysis of the complexity scores were found to correlate to differences between measurements and calculations with a Pearson's r-value of 0.97.