详情

At present, IMRT and VMAT technology have become the most important radiotherapy technologies nowadays. Both of them are known for their high efficiency, complexity and accuracy. Therefore, they need to be supplemented by more convenient, rigorous and precise quality assurance to ensure the effect of radiotherapy.

At present, there are many devices used for pre-treatment dose verification with different characteristics. Studies have shown that EPID can be equivalent to conventional dose verification tools (Map CHECK, Arc CHECK, Matrixx and other dose verification tools) through calibration. Secondly, because EPID is directly integrated in the LINAC, it can satisfy both pre-treatment dose verification and even real-time dose monitoring during treatment without the need for auxiliary tools and without affecting the treatment.

The R&D team of LinaTech has launched the EPID-based Plan QA technology, which uses the EPID and the Monte-Carlo-based dose reconstruction algorithm to verify the planned dose of patients before treatment. This technology has the advantages of large detection area (Arm improves detection range), high resolution (more accurately detailed information and dose gradient), non-angle response (and angle synchronization with the treatment head), strong radiation resistance and easy to use, etc. It can be used as an effective and convenient dose verification tool to ensure the quality and efficiency of radiotherapy.

The technology has been tested extensively in Changzhou Second Hospital. The dose calculated by the Pinnacle planning system is compared with the dose measured by Mapcheck and the dose reconstructed by EPID. The statistical γ (3mm, 3%, 10%) results are shown in Table 1. The analysis shows that when the γ standard is 3%/3mm, the results of the γ pass rate verified by EPID and Mapcheck are close, and there is no statistical difference (p=0.55>0.05), which basically meets the needs of clinical application.

Table 1 Comparison of EPID verification results and MapCheck verification results

With the development of EPID technique, in the future, LinaTech R&D team will continue to work hard to apply this technology to more advanced adaptive dose-guided radiotherapy, in order to reach the world's advanced level.

EPID Schematic