Abstract
BACKGROUND: Prior to the development of the IMRT and VMAT treatment techniques the quality assurance (QA) paradigm was one of routine linac QA supplemented by plan specific independent Monitor Unit checks and manual checks of data transfer. With the introduction of IMRT/VMAT treatment techniques the paradigm changed to include a patient specific measurement (PSQA) to ensure acceptable plan deliverability. PURPOSE: To inform upon whether QA procedures have improved to the point that measurement-based PSQA is feasibly no longer required. METHODS: The current status and future trajectory of QA procedures is assessed via a review of the literature pertaining to each of the three sub-systems of deliverability, namely, treatment planning system (TPS) calculation accuracy, linac delivery performance, and data transfer between treatment planning system and linac. RESULTS: The literature pertaining to 3D TPS dosimetry check systems used to assure TPS calculation accuracy is highly positive about such systems ability to provide at least equivalent level testing as measurement based PSQA with regards TPS calculation accuracy. The literature suggests that linac QA procedures have evolved since the advent of IMRT and methodology has been published for assessing the linac in its dynamic state used to deliver IMRT/VMAT. Data transfer QA has also evolved since the advent of IMRT and tests and procedures are now recommended in best practice guidance for both comprehensive data transfer QA programs and pre-treatment checking and chart rounds. Additionally, the uptake of log file-based QA methods provides a useful means of testing control point data transfer integrity. CONCLUSIONS: Contemporary sub-system deliverability QA has evolved to the point where measurement based PSQA is not necessarily required.