Stereotactic radiotherapy for patients with metallic implants on vertebral body: A dosimetric comparison

Abstract

Objective: Metallic implants have impacts on dose distribution of radiotherapy. Our purpose is evaluating impact of metallic implants with different dose calculation algorithms on dose distribution. Material and Methods: Two patients with metallic implants on vertebral body were included in this study. They were treated with stereotactic radiotherapy. The data of the patients were retrospectively re-calculated with different TPSs and calculation algorithms. Ray-Tracing (Ry-Tc), Monte-Carlo (MC), Acuros XB (AXB) and analytical anisotropic algorithms (AAA) were compared. Results: Ry-Tc, AAA and AXB underestimated minimum and maximum doses of target volumes and critical organs compared with MC. Conclusion: MC seems more reliable for dose calculations in patients with metallic implants but more studies with more number of patients should be done to identify the best dose calculation algorithm for patients with metallic implants.

Keywords

• Prostheses and Implants,Stereotactic Body Radiotherapy,Monte-Carlo method,Acuros XB

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