New device enables hospitals to verify accuracy of eye cancer radiation treatments
Researchers have developed and tested a compact device that allows hospitals to independently verify the accuracy of radioactive applicators used to treat ocular tumors, addressing a critical gap in quality assurance for this specialized cancer treatment. The BetaCheck-106™ system could help standardize safety protocols across clinics and reduce reliance on manufacturer data alone.
Originaltitel: Evaluation of a water phantom detector‐applicator setup for independent experimental verification of <sup>106</sup> Ru ocular brachytherapy applicators
Abstract Background 106 Ru ophthalmic brachytherapy (BT) applicators are used for treating ocular tumors. While manufacturer‐provided dosimetry data is commonly used for treatment planning, independent quality assurance (QA) measurements are crucial. However, there is a lack of dedicated equipment and standardized protocols for clinical verification of 106 Ru depth‐dose distributions. Purpose The BetaCheck‐106™ is a prototype compact water phantom detector‐applicator setup enabling high precision alignment of 106 Ru applicators and detectors. We assess the setup's compatibility with three commercially available detectors (microSilicon, microSilicon X and microDiamond) and its performance in determining full 1D depth‐current curves with these detectors. In addition, data from clinical QA‐tests of 20 106 Ru applicators was used to estimate inhomogeneities in the applicator's 106 Ru coating. Methods Measurements were conducted on two 106 Ru applicators with different activity levels, one had been in clinical service for one year and one was measured before clinical use. Dose rates were recorded at 1 mm intervals from 2 mm to 10 mm in water using the BetaCheck‐106™ setup with the three detectors. Measurement precision and detector response were analyzed. Separately, inter‐applicator variability was analyzed using the aforementioned measurements of 20 106 Ru applicators. Results The BetaCheck‐106™ demonstrated exceptional setup reproducibility (0.23%), enabling precise depth‐resolved measurements. Both of the silicon diode detectors examined provided stable and reproducible measurements. The diamond detector performed reproducibly for the high‐activity applicator but exhibited depth‐dependent signal instability for the low‐activity source, likely due to the detector's lower sensitivity. Normalized depth‐signal curves for the three detectors all had similar shape. Analysis of measured current per activity of 20 106 Ru applicators revealed a depth dependent inhomogeneity effect decreasing with depth. Conclusions The BetaCheck‐106™ provides practical high‐reproducibility positioning of detector and applicator for 106 Ru applicator measurements in water. The silicon detectors successfully characterized both high and low activity applicators up to 10 mm water depth. The diamond detector proved viable for measurements of the applicator with activity 17.8–18.4 MBq, but it lost stability with depth when measuring the one‐year old 8.3 MBq activity applicator.