Validation of 3DVH estimated DVH metrics for prostate VMAT plans

8th International Conference on 3D Radiation Dosimetry

Arumugam, Sankar^1 ; Xing, Aitang^1 ; Young, Tony^1 ; Thwaites, David^2 ; Holloway, Lois^1,2,3,4

Liverpool and Macarthur Cancer Therapy Centres, Ingham Institute, NSW, Australia^1

Institute of Medical Physics, School of Physics, University of Sydney, NSW, Australia^2

Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia^3

Uinversity of New South Wales, NSW, Australia^4

关键词: Multileaf collimators;    Organs at risks;    Positioning error;    Small data set;    Target volumes;    Treatment sites;    Volumetric modulated arc therapy;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/573/1/012053/pdf
DOI  :  10.1088/1742-6596/573/1/012053

来源: IOP

【 摘 要 】

The accuracy of 3DVH (Sun Nuclear Corporation, USA) reported DVH metrics for target volumes and Organs at Risk (OARs) for two Prostate Volumetric Modulated Arc Therapy (VMAT) plans was studied. The accuracy of 3DVH estimated DVH metrics in the presence of Multi Leaf Collimator (MLC) systematic errors was also tested with error introduced plans calculated in Pinnacle. The results of the study show that the DVH metrics estimated by 3DVH for error-free plans agree with the TPS calculation within 3%. The D95 to PTV was shown to be sensitive in detecting studied MLC errors. However the accuracy of 3DVH estimated DVH metrics for Target Volumes and OARs in the presence of MLC errors for VMAT prostate plans has limitations with this small data set. Although for most situations values matched within 3% for small MLC errors, there was up to a 9.8% difference between the TPS and 3DVH in the presence of a simulated 5mm MLC positioning error. Further study with more plans including other treatment sites is required to fully assess the performance of 3DVH in detecting potential clinical delivery errors.