Skarsgard L D, Douglas B G, Denekamp J, Chaplin D J, Lam G K, Harrison R W, Kornelsen R O, Palcic B
Radiat Res Suppl. 1985;8:S135-44.
Patient treatments at TRIUMF (Tri-University Meson Facility, Vancouver, B. C.) use a moving spot raster scan technique where the pion range is modulated in depth for each position of the moving spot. The spot scans in a stepwise fashion and can produce any desired field shape. This approach provides very good dose uniformity across the treatment field and allows maximum flexibility in shaping the treatment volume. Survival of cultured cells has been used as a biological dosimeter to test the isoeffectiveness of the pion dose distributions, which must be shaped in depth to compensate for the depth-dependent LET distribution. Isoeffectiveness across the treatment field has also been verified using this system, which involves irradiating cells supported in a gelatin matrix. The response of pig skin to pion irradiation at TRIUMF has provided a check on the in vivo RBE for acute effects derived from our earlier studies with mouse foot. In addition, the pig skin reactions have been followed for several months to assess the later dermal response. The RBE of our pion beam relative to 270 kVp X rays is approximately 1.5 for both the acute epidermal and the later dermal responses.
位于不列颠哥伦比亚省温哥华的三大学介子设施（TRIUMF）对患者的治疗采用移动束斑光栅扫描技术，其中对于移动束斑的每个位置，π介子射程在深度上进行调制。束斑以逐步方式扫描，并可产生任何所需的射野形状。这种方法在整个治疗野中提供了非常好的剂量均匀性，并在塑造治疗体积方面具有最大的灵活性。培养细胞的存活已被用作生物剂量计，以测试π介子剂量分布的等效应性，该剂量分布必须在深度上进行塑形以补偿与深度相关的传能线密度（LET）分布。使用该系统也已验证了整个治疗野的等效应性，该系统涉及照射支撑在明胶基质中的细胞。TRIUMF的猪皮肤对π介子照射的反应对我们早期对小鼠足部研究得出的急性效应的体内相对生物效应（RBE）进行了检验。此外，对猪皮肤反应进行了数月跟踪，以评估后期的皮肤反应。对于急性表皮反应和后期皮肤反应，我们的π介子束相对于270 kVp X射线的RBE约为1.5。
