Center of Translational Cancer Research, Technische Universität München (TranslaTUM), Campus Klinikum rechts der Isar, Department of Radiation Oncology, Klinikum rechts der Isar, Munich, Germany.
Center of Translational Cancer Research, Technische Universität München (TranslaTUM), Campus Klinikum rechts der Isar, Department of Radiation Oncology, Klinikum rechts der Isar, Munich, Germany.
Int J Radiat Oncol Biol Phys. 2018 Jul 1;101(3):671-679. doi: 10.1016/j.ijrobp.2018.02.017. Epub 2018 Feb 14.
The aim was to reduce radiation exposure of the lung in experimental models to increase overall survival of mice to study late radiation-induced heart disease.
A new irradiation plan was established on the Small Animal Radiation Research Platform machine for local heart irradiation of mice with single doses of 8 and 16 Gy. Lung damage was analyzed 20, 30, 40, and 50 weeks after irradiation by computed tomography scans and histology and compared with a sham-irradiated, age-matched, control group.
The use of an 8 × 6-mm collimator enabled local heart irradiation whereby only 18% of the lung received any irradiation. The V10 and V16 of the lung were 14% and 7%, respectively. After a mean heart dose of 8 and 16 Gy, mice survived for at least 50 weeks after irradiation. Computed tomography images demonstrated increased cell densities in the irradiated lung volume 50 weeks after irradiation. Concomitantly, histologic examination revealed fibrotic and inflammatory changes in the irradiated lung volume. In the heart, amyloid depositions and left ventricle hypertrophy were observed.
High-precision heart irradiation with 8 and 16 Gy using an 8 × 6-mm beam induced cardiac amyloidosis and hypertrophy, which did not lead to myocardial dysfunction despite the presence of radiation pneumopathy in the small V16 of the exposed lung. By using the improved irradiation plan (V16: 7%), long-term survival of the mice after heart irradiation can be achieved that allows clinically relevant experimental investigation of late radiation-induced heart disease effects.
旨在减少实验模型中肺部的辐射暴露，以提高小鼠的总生存率，从而研究晚期放射性心脏病。
在小动物放射研究平台机器上建立了一种新的照射计划，用于对小鼠进行单次 8 和 16 Gy 的局部心脏照射。通过计算机断层扫描和组织学分析，在照射后 20、30、40 和 50 周时分析肺损伤，并与假照射、年龄匹配的对照组进行比较。
使用 8×6mm 的准直器可以进行局部心脏照射，只有 18%的肺部受到任何照射。肺的 V10 和 V16 分别为 14%和 7%。在平均心脏剂量为 8 和 16 Gy 后，照射后小鼠至少存活 50 周。照射后 50 周的 CT 图像显示照射肺体积的细胞密度增加。同时，组织学检查显示照射肺体积出现纤维化和炎症改变。在心脏中，观察到淀粉样沉积物和左心室肥大。
使用 8×6mm 的光束进行 8 和 16 Gy 的高精度心脏照射会导致心脏淀粉样变性和肥大，但尽管暴露肺的小 V16 中存在放射性肺炎，但不会导致心肌功能障碍。通过使用改进的照射计划（V16：7%），可以实现心脏照射后小鼠的长期存活，从而能够对晚期放射性心脏病的影响进行临床相关的实验研究。
