Abstract

The aim of the study was to evaluate dose distributions on the superficial cardiac lesion surrounded by low-density lungs. Volumetric modulated arc therapy (VMAT) technique was applied to optimize the dose distribution using the anisotropic analytic algorithm (AAA) and Acuros XB algorithm (AXB) using the 3-D printed cardiac phantom. We used four full and half arcs with 6-MV and 15-MV photons to investigate the rebuild-up effect near the planning target volume (PTV). Depending on the calculation algorithm (AAA vs. AXB) for full arcs plans, V95 of PTV differed by 27% for 6-MV and 29% for 15-MV, and D95 for 6-MV and 15-MV shows 24% and 30%, respectively. The maximum doses in the AXB plans on PTV were 5.1% higher than those in AAA plans at 6-MV, and 3.8% higher at 15-MV. In addition, half arcs treatment plans showed a very similar tendency with full arcs plans. Film dosimetry showed significant differences from the planned results in the AAA plans. Particularly, the dose mismatch occurred between the cardiac PTV and the left lung interface. In the case of 6-MV plans calculated by AAA, the maximum dose increased from 4.1 to 7.7% in the PTV. Furthermore, it showed that 50% of the width of dose profiles was reduced by 1.3 cm in the 6-MV plan. Conversely, in the case of the plans using the AXB algorithm, the maximum dose increased by 2.0–5.0%. In contrast to the AAA algorithm, the dose patterns at the interface demonstrated a good agreement with the plans. Dose fluctuation on the interface between superficial cardiac lesions and low-density lungs can lead to an error in the estimation of accurate dose delivery for the case of VT SBRT.

Highlights

  • The aim of the study was to evaluate dose distributions on the superficial cardiac lesion surrounded by low-density lungs

  • radiation-induced lung injury (RILI) encompasses lung toxicity induced by RT that acutely manifests itself as radiation pneumonitis, bronchiolitis obliterans organizing pneumonia (BOOP), and chronically as radiation pulmonary f­ibrosis[12,13]

  • The aim of this study is to evaluate the rebuild-up effect and dose discrepancy based on the measured dose distributions as compared to the calculated doses from AXB and analytic algorithm (AAA) algorithms for superficial cardiac lesion surrounded by low-density lungs using a 3-D printed cardiac phantom

Read more

Summary

Introduction

The aim of the study was to evaluate dose distributions on the superficial cardiac lesion surrounded by low-density lungs. Depending on the calculation algorithm (AAA vs AXB) for full arcs plans, ­V95 of PTV differed by 27% for 6-MV and 29% for 15-MV, and ­D95 for 6-MV and 15-MV shows 24% and 30%, respectively. In the case of 6-MV plans calculated by AAA, the maximum dose increased from 4.1 to 7.7% in the PTV. It showed that 50% of the width of dose profiles was reduced by 1.3 cm in the 6-MV plan. Dose fluctuation on the interface between superficial cardiac lesions and low-density lungs can lead to an error in the estimation of accurate dose delivery for the case of VT SBRT. RILI encompasses lung toxicity induced by RT that acutely manifests itself as radiation pneumonitis, bronchiolitis obliterans organizing pneumonia (BOOP), and chronically as radiation pulmonary f­ibrosis[12,13]

Objectives
Results
Conclusion
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.