Magnetic resonance imaging (MRI) system is used as one of the most common methods to read out the response of polymer gel dosimeters. The imaging protocols can have a remarkable effect on the response of polymer gel dosimeters; hence, the impact of imaging parameters on the response of each type of polymer gel dosimeter should be addressed. This study aims to investigate the effect of MRI parameters on PASSAG polymer gel dosimeter response. PASSAG gel dosimeter was first fabricated and then, these gel samples were irradiated by a 6 MV X-rays. Thereafter, the MRI responses (R₂) of the gel samples were analyzed. In addition, the impact of MRI parameters, including number of echoes (NOE), echo spacing (ES), repetition time (TR), and matrix size, on the sensitivity and dose resolution of the gel samples were evaluated. The findings showed that the highest R₂–dose sensitivity belongs to the gel samples imaged with 32 NOE. It was also found that the dose resolution value improves with the increase of NOE. The R₂–dose sensitivities and dose resolution values obtained from PASSAG gel samples imaged with ESs of 16.8, 22.0, and 27.2 ms were almost the same. Furthermore, the R₂–dose sensitivities of gel vials imaged with TRs of 2000, 4000, and 6000 ms are almost the same (a 0.00–0.80% difference range), while the R₂–dose sensitivity of gel vials imaged with 8000 ms was remarkably different from the sensitivities of gel vials imaged with other TRs (a 7.85–8.65% difference range). In addition, the dose resolution values of PASSAG gel dosimeter are almost the same for the evaluated TRs. There was a 0.80–11.58% difference range between the R₂–dose sensitivities of gel vials at different matrix sizes, as these findings represent that the R₂–dose sensitivity of PASSAG gel dosimeter is dependent on the matrix size. In addition, the dose resolution values of PASSAG gel dosimeter vary over the matrix size. According to the obtained results, it can be concluded that the TR and matrix size affect the response (R₂–dose sensitivity and dose resolution) of PASSAG gel dosimeter more than the NOE and ES.

磁共振成像 (MRI) 系统被用作读取聚合物凝胶剂量计响应的最常用方法之一。成像协议对聚合物凝胶剂量计的响应有显着影响；因此，应解决成像参数对每种聚合物凝胶剂量计响应的影响。本研究旨在研究 MRI 参数对 PASSAG 聚合物凝胶剂量计响应的影响。PASSAG 凝胶剂量计首先被制造出来，然后，这些凝胶样品被 6 MV X 射线照射。此后，MRI反应（R ₂) 的凝胶样品进行了分析。此外，还评估了 MRI 参数对凝胶样品的灵敏度和剂量分辨率的影响，包括回波数 (NOE)、回波间距 (ES)、重复时间 (TR) 和矩阵大小。结果表明，最高的R ₂剂量敏感性属于使用 32 NOE 成像的凝胶样品。还发现剂量分辨率值随着NOE的增加而提高。从使用 16.8、22.0 和 27.2 ms 的 ES 成像的 PASSAG 凝胶样品获得的R ₂剂量敏感性和剂量分辨率值几乎相同。此外，R ₂使用 2000、4000 和 6000 ms 的 TR 成像的凝胶小瓶的剂量敏感性几乎相同（差异范围为 0.00-0.80%），而使用 8000 ms 成像的凝胶小瓶的R ₂剂量敏感性与使用其他 TR 成像的凝胶小瓶的灵敏度（7.85-8.65% 的差异范围）。此外，PASSAG 凝胶剂量计的剂量分辨率值与评估的 TR 几乎相同。不同基质尺寸的凝胶小瓶的R ₂剂量敏感性之间存在 0.80–11.58% 的差异范围，因为这些发现表明R ₂– PASSAG 凝胶剂量计的剂量灵敏度取决于基质大小。此外，PASSAG 凝胶剂量计的剂量分辨率值随基质大小而变化。根据获得的结果，可以得出结论，TR 和基质大小对PASSAG 凝胶剂量计的响应（R _{2 -}剂量敏感性和剂量分辨率）的影响大于 NOE 和 ES。