¹²⁵I 和 ¹⁶⁹Yb 近距离治疗剂量学中各种探测器材料能量响应的蒙特卡罗研究。

Monte Carlo investigation of energy response of various detector materials in ¹²⁵I and ¹⁶⁹Yb brachytherapy dosimetry.

机构信息

Radiological Physics and Advisory Division, Health, Safety and Environment Group, Bhabha Atomic Research Centre, Mumbai, India.

出版信息

J Appl Clin Med Phys. 2010 Jul 28;11(4):3282. doi: 10.1120/jacmp.v11i4.3282.

Relative absorbed-dose energy response correction R for different detector materials in water, PMMA and polystyrene phantoms are calculated using Monte Carlo-based EGSnrc code system for ¹²⁵I and ¹⁶⁹Yb brachytherapy sources. The values of R obtained for ¹²⁵I source are 1.41, 0.92, 3.97, 0.47, 8.32 and 1.10, respectively, for detector materials LiF, Li₂B₄O₇ , A1₂O₃, diamond, silicon diode and air. These values are insensitive to source-to-detector distance and phantom material. For ¹⁶⁹Yb source, R is sensitive to source-to-detector distance for detector materials other than air and Li₂B₄O₇. For silicon, R increases from 3 to 4.23 when depth in water is increased from 0.5 cm to 15 cm. For ¹⁶⁹Yb source, the values of R obtained for air and Li₂B₄O₇ in PMMA and polystyrene phantoms are comparable to that obtained in water. However, LiF, Si and A1₂O₃ show enhanced response and diamond shows decreased response in PMMA and polystyrene phantoms than in water.

使用基于蒙特卡罗的 EGSnrc 代码系统，针对 ¹²⁵I 和 ¹⁶⁹Yb 近距离治疗源，计算了水、PMMA 和聚苯乙烯体模中不同探测器材料的相对吸收剂量能量响应修正因子 R。对于 ¹²⁵I 源，LiF、Li₂B₄O₇、A1₂O₃、金刚石、硅二极管和空气的 R 值分别为 1.41、0.92、3.97、0.47、8.32 和 1.10。这些值对源与探测器的距离和体模材料不敏感。对于 ¹⁶⁹Yb 源，除空气和 Li₂B₄O₇ 之外的探测器材料的 R 值对源与探测器的距离敏感。对于硅，当水的深度从 0.5cm 增加到 15cm 时，R 从 3 增加到 4.23。对于 ¹⁶⁹Yb 源，空气和 Li₂B₄O₇ 在 PMMA 和聚苯乙烯体模中的 R 值与在水中的 R 值相当。然而，LiF、Si 和 A1₂O₃ 在 PMMA 和聚苯乙烯体模中的响应增强，而金刚石的响应降低。