Abstract：
Purpose. Secondary skin collimation (SSC) is essential for shielding normal tissues near tumors during electron and orthovoltage radiation treatments. Traditional SSC fabrication methods, such as crafting in-house lead sheets, are labor-intensive and produce SSCs with low geometric accuracy. This study introduces a workflow that integrated 3D scanning and 3D printing technologies with an in-house mold process, enabling the production of patient-specific SSCs within six hours.Methods. An anthropomorphic head phantom was scanned with a handheld 3D scanner. The resulting scan data was imported into 3D modeling software for design. The completed model was exported to a 3D printer as a printable file. Subsequently, molten Cerrobend was poured into the mold and allowed to set, completing the SSC production. Geometric accuracy was assessed using CT images, and the shielding effectiveness was evaluated through film dosimetry.Results. The 3D printed mold achieved submillimeter accuracy (0.5 mm) and exhibited high conformity to the phantom surface. It successfully endured the weight and heat of the Cerrobend during pouring and curing. Dosimetric analysis conducted with radiochromic film demonstrated good agreement between the measured and expected attenuation values of the SSC slab, within ±3%.Conclusions. This study presents a proof of concept for novel mold room workflows that produce patient-specific SSCs within six hours, a significant improvement over the traditional SSC fabrication process, which takes 2-3 days. The submillimeter accuracy and versatility of 3D scanning and printing technologies afford greater design freedom and enhanced delivery accuracy for cases involving irregular geometries.
摘要：
目的：二次皮肤准直（SSC）对于在电子和正电压放射治疗期间屏蔽肿瘤附近的正常组织至关重要。传统的SSC制造方法，比如制作内部铅片，是劳动密集型的，并生产具有低几何精度的SSC。这项研究介绍了一个工作流程，将3D扫描和3D打印技术与内部模具工艺集成在一起，能够在6小时内生产患者特异性SSC。＆＃xD;方法：用手持式3D扫描仪扫描拟人化的头部体模。将得到的扫描数据导入到3D建模软件中进行设计。完成的模型作为可打印文件导出到3D打印机。随后，将熔化的Cerrobend倒入模具中并使其凝固，完成SSC生产。使用CT图像评估几何精度，并通过薄膜剂量学对屏蔽效能进行评价。＆＃xD;结果：3D打印模具实现了亚毫米精度（0.5毫米），并表现出与体模表面的高度一致性。在浇注和固化过程中，它成功地承受了Cerrobend的重量和热量。使用辐射变色胶片进行的剂量学分析显示，SSC平板的测量衰减值与预期衰减值之间具有良好的一致性。±3%以内。＆＃xD;结论：这项研究为新颖的模具室工作流程提供了概念证明，该流程在六个小时内产生患者特定的SSC，比传统的SSC制造工艺有了显著的改进，这需要2-3天。3D扫描和打印技术的亚毫米精度和多功能性为涉及不规则几何形状的情况提供了更大的设计自由度和增强的交付精度。
