DICOM-RT Plan Complexity Verification for Volumetric Modulated Arc Therapy

DOI: 10.4236/ijmpcero.2014.33017   PDF   HTML     3,953 Downloads   5,980 Views   Citations


The purpose of this study was to investigate the relationship between plan parameters verified with DICOM-RT and dosimetric results for volumetric modulated arc therapy (VMAT). We investigated three treatment locations: prostate cancer (ten cases), maxillary sinus cancer (four cases), and malignant pleura mesothelioma (four cases) with treatment plans generated by a MonacoTM treatment planning system (TPS), and delivered with an Elekta SynergyTM linear accelerator. We calculated plan parameters, including gantry and multileaf collimator (MLC) positions, Monitor Units (MU), and millimeters of MLC motion per degree of gantry rotation (mm/degree), and performed quality assurance (QA) with a DICOM-RT plan verification system. We measured the VMAT dose with a two-dimensional diode array detector. The average gamma passing rate with percent dose acceptance criteria and distance to agreement criteria of 2 mm and 2% (2 mm/2%) were 97.4%, 97.8% and 92.0% for prostate cancer, maxillary sinus cancer, and malignant pleural mesothelioma, respectively. The mean 95th percentile value for DICOM-calculated mm/degree was 4.0, 5.2, and 11.1 for prostate cancer, maxillary sinus cancer, and malignant pleural mesothelioma, respectively. The gamma passing rate showed a correlation with calculated mm/degree, with a coefficient of determination (R2) of 0.60. Higher calculated mm/degree values led to increased dosimetric errors. We conclude that dose distribution calculated by a TPS is more reliable at smaller mm/degree.

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Miura, H. , Tanooka, M. , Inoue, H. , Fujiwara, M. , Kosaka, K. , Doi, H. , Takada, Y. , Odawara, S. , Kamikonya, N. and Hirota, S. (2014) DICOM-RT Plan Complexity Verification for Volumetric Modulated Arc Therapy. International Journal of Medical Physics, Clinical Engineering and Radiation Oncology, 3, 117-124. doi: 10.4236/ijmpcero.2014.33017.

Conflicts of Interest

The authors declare no conflicts of interest.


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