An in vivo dose verification method for SBRT–VMAT delivery using the EPID

Abstract

The authors have customized and validated a robust, physics-based model that calculates the delivered dose to a patient for SBRT-VMAT delivery using on-treatment EPID images. The accuracy of the results indicates that this approach is suitable for clinical implementation. Future work will incorporate this model into both offline and real-time clinical adaptive radiotherapy.

The use of 0.5rcav as an effective point of measurement for cylindrical chambers may result in a systematic shift of electron percentage depth doses

“…The diodes used in this study were the PTW 60017 Diode‐E (PTW, Freiburg, Germany) and the IBA SFD (IBA‐Scanditronix, Uppsala, Sweden). The Diode‐E is a diode detector designed for use in electron dosimetry while the SFD is a micro‐size sensitive volume detector used in small field dosimetry . The SFD is also suitable for electron dosimetry according to the manufacturer.…”

Retrospective Cohort Study of Bronchial Doses and Radiation-Induced Atelectasis After Stereotactic Body Radiation Therapy of Lung Tumors Located Close to the Bronchial Tree

“…McCowan et al, calculations with AAA compared to CC result in a 2-5% lower lung dose, and up to 5% higher dose in the tissue where the radiation exits the lung (McCowan, Van Uytven, Van Beek, Asuni, & McCurdy, 2015). Latifi et al (2014) report statistically significant higher rates of local recurrences after SBRT of NSCLC calculated with PB compared to those calculated with CC; 21.5% (crude rate) with PB and 4.7% with CC.…”

“…This method was shown to be as good as the accumulated dose calculated on the 4DCT phases for regular breathing motion, but better for irregular breathing motions. Another use of the EPID images was implemented by McCowan et al (2015), who created a model for reconstruction of the delivered dose using the EPID images acquired during treatment and Monte Carlo simulations of the fluence.…”

Epid‐based in vivo dose verification for lung stereotactic treatments delivered with multiple breath‐hold segmented volumetric modulated arc therapy

“…McCowan et al. have recently validated an in‐house physics‐based model which utilizes EPID images to reconstruct the dose in patient during SBRT‐VMAT treatments . The authors reported satisfactory results for lung and spine cases, with pass rates better than 93% with 3%‐3 mm γ ‐index tolerance level, showing the suitability of this approach for clinical implementation.…”