Author: Guang-Pei Chen, Mi Huang, Haidy G. Nasief, Eric S. Paulson 👨🔬
Affiliation: Department of Radiation Oncology, Medical College of Wisconsin 🌍
Purpose: Recently, kV imaging has been integrated into the Accuray Radixact platform, facilitating online adaptive and scan-plan-treat workflows with helical delivery in the near future. In order to support these workflows, rapid quality assurance (QA) is essential. In this work we developed a software-based tool for fast and robust online treatment plan and delivery QA.
Methods: A software QA tool, CQA, was developed to retrieve data from the iDMS database via SQL query. Planning elements including images, structure sets, patient and machine setup, dose prescription, dose-volume parameter goals and results, IGRT shifts, and delivery records, etc, are evaluated with CQA using data from 12 prostate patients. A nomogram was developed to estimate beam-on time as a function of various parameters including target site/size, fractional dose, modulation factor, and jaw width. The integrity of plan transfer to the Mosaiq record and verify system is also verified.
Results: Identifying gross errors in beam-on time using CQA was feasible with the developed nomogram. The linear fit on the relationship of beam-on time and the plan parameters yields an R2 of 0.90. CQA successfully verified treatment planning and delivery parameters in three stages during: i) plan quality, including consistency of demographics in iDMS and Mosaiq, correctness of images, RT-structures, couch insertion, patient setup, mass density model, machine parameters, dose optimization, calculation and achieved dose-volume parameters, ii) data transfer, including beam-on time and plan UID sent to Mosaiq, and iii) consistency of the planned and delivered parameters, as well as the appropriateness of IGRT shifts.
Conclusion: We created CQA, a software-based tool for rapid online treatment plan and delivery QA on the Radixact platform. It can effectively and independently QA the entire planning and delivery on the highly-integrated Radixact system within 30 seconds, supporting future online adaptive and scan-plan-treat workflows on Radixact treatment.