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arXiv · 1809.09361

Automatizing a non-scripting TPS for optimizing clinical workflow and re-optimization of IMRT/VMAT plans

Rafael Ayala·Gema Ruiz·Teresa Valdivielso
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Abstract

A toolkit for interacting with the Elekta Monaco (Clements et al 2018) treatment planning system (TPS) has been designed without the need of a dedicated Application Programming Interface (API). It provides automatization of the radiotherapy planning procedure allowing the TPS to calculate or optimize plans during non-working hours. The software is based on an open source library that mimics human interaction with Microsoft Windows applications. The impact on the clinical workflow is important not only providing better efficiency but also increasing treatment quality. Successful inverse planning depends on the tweaking of many parameters that can be explored more exhaustively with this tool without significantly increasing planning time. Furthermore, a simple way to analyze calculated plans and the impact of the cost functions in the optimization has been implemented. The Autoflow sequence has been developed allowing fully automated planning; it works analyzing the relative impact of different cost functions in the optimization and modifying constraints accordingly. It also changes segmentation parameters to fit more complex treatments. A prostate study has been conducted, comparing automatically created plans with already treated ones. The Autoflow sequence has proved to reduce dose to organs at risk with a negligible decrease in target coverage. Implementing this tool has enabled an efficient use of the TPS, allowing research and clinical use to coexist in a friendly way. It is surely of great use in clinics with little resources. It provides consistency and efficiency throughout the treatment planning process.

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Rafael Ayala, Gema Ruiz, Teresa Valdivielso. 2018-09-25. Automatizing a non-scripting TPS for optimizing clinical workflow and re-optimization of IMRT/VMAT plans. https://doi.org/10.1016/j.meddos.2019.02.006

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