Kumagai Shinobu, Arai Norikazu, Takata Takeshi, Kon Daisuke, Saitoh Toshiya, Oba Hiroshi, Furui Shigeru, Kotoku Jun'ichi, Shiraishi Kenshiro
Central Radiology Division, Teikyo University Hospital, Tokyo, Japan.
Graduate School of Medical Care and Technology, Teikyo University, Tokyo, Japan.
J Contemp Brachytherapy. 2020 Feb;12(1):53-60. doi: 10.5114/jcb.2020.92401. Epub 2020 Feb 28.
To share the experience of an iridium-192 (Ir) source stuck event during high-dose-rate (HDR) brachytherapy for cervical cancer.
In 2014, we experienced the first source stuck event in Japan when treating cervical cancer with HDR brachytherapy. The cause of the event was a loose screw in the treatment device that interfered with the gear reeling the source. This event had minimal clinical effects on the patient and staff; however, after the event, we created a normal treatment process and an emergency process. In the emergency processes, each staff member is given an appropriate role. The dose rate distribution calculated by the new Monte Carlo simulation system was used as a reference to create the process.
According to the calculated dose rate distribution, the dose rates inside the maze, near the treatment room door, and near the console room were ≅ 10 [cGy · h], 10 [cGy · h], and << 10 [cGy · h], respectively. Based on these findings, in the emergency process, the recorder was evacuated to the console room, and the rescuer waited inside the maze until the radiation source was recovered. This emergency response manual is currently a critical workflow once a year with vendors.
We reported our experience of the source stuck event. Details of the event and proposed emergency process will be helpful in managing a patient safety program for other HDR brachytherapy users.
分享宫颈癌高剂量率（HDR）近距离放射治疗期间铱 - 192（Ir）源滞留事件的经验。
2014年，我们在日本用HDR近距离放射治疗宫颈癌时经历了首例源滞留事件。事件原因是治疗设备中的一颗螺丝松动，干扰了卷源齿轮。该事件对患者和工作人员的临床影响极小；然而，事件发生后，我们制定了正常治疗流程和应急流程。在应急流程中，为每位工作人员分配了适当角色。新的蒙特卡罗模拟系统计算出的剂量率分布被用作制定流程的参考。
根据计算出的剂量率分布，迷宫内部、治疗室门附近和控制台室附近的剂量率分别约为10 [cGy·h]、10 [cGy·h]和远低于10 [cGy·h]。基于这些发现，在应急流程中，记录员被疏散到控制台室，救援人员在迷宫内部等待，直到放射源被回收。这份应急响应手册目前每年与供应商进行一次关键流程演练。
我们报告了源滞留事件的经验。该事件的详细情况和提议的应急流程将有助于其他HDR近距离放射治疗用户管理患者安全计划。
