目的:应用3D打印支架联合人造金刚石探头测量施源器材料对高剂量率后装 192Ir源水中吸收剂量的影响。 方法:将金刚石探头与塑料插植针分别固定在3D打印支架上，金刚石探头的中心轴与塑料插植针的中心轴在一个平面内相互垂直。采用模拟源尺测量实测驻留位置为248 mm，该驻留位置与逐点测量的最大响应位置吻合。测量材料有304不锈钢、聚亚苯基砜树脂(PPSU)材料、有机玻璃(PMMA)材料和3D打印聚乳酸(PLA)材质。测量水中不同厚度或不同填充率的材料对吸收剂量的衰减。结果:304不锈钢和PPSU材料厚度与相对剂量的线性拟合公式分别为 y＝-0.029 7 x＋1.000 3， y＝-0.002 3 x＋1.010 2；拟合优度 R2分别为0.925 3和0.722 2。10 mm以内PMMA材料对剂量的影响均<1.5%。3D打印材料填充率(%)与相对剂量的线性拟合公式为 y＝-0.000 4 x＋1.024 6，拟合优度 R2为0.854 5。 结论:施源器材料，尤其是高密度材料(如304不锈钢)和新型技术材料(如3D打印PLA)，对 192Ir后装源的吸收剂量影响需引起施源器开发人员和临床应用者的足够重视。

目的：:分析 60Co外照射加高剂量率后装腔内放射治疗鼻咽癌的长期疗效及晚期放射性并发症。 材料与方法：:回顾性分析1981年6月至1988年12月采用 60Co外照射加高剂量率后装腔内放射治疗鼻咽癌64例。本组病例都随访5年以上，失访者作死亡统计。 结果：:本组病例5年局部控制率为82.8%（53/64）。5年生存率和无瘤生存率分别为75.0%（48/64）和68.8%（44/64）。鼻咽局部复发6例，远处转移8例、鼻腔骨肉瘤者1例。晚期放射并发症，鼻腔死骨形成1例，软硬腭骨穿孔4例。结论：:后装腔内放射治疗适当减少鼻咽癌外照射剂量，增加鼻咽腔内加量照射。适应于鼻咽早期原发肿瘤和鼻咽癌外照射后鼻咽腔内残留病灶。为了减少鼻咽腔内晚期放射性并发症值得进一步改进鼻咽施源器。

Purpose:To compare the local control rate and side effects of external radiation combined with brachytherapy and external radiation alone for early nasopharyngeal carcinoma (NPC).Materials and Methods:A total of 124 patients with T 1, T 2 NPC was evaluated in this study between March 1990 and November 1996. The median follow-up periods were 62 months with 5 cases lost. There were male 86, female 38. The ages ranged from 16~70 yrs. Poorly differentiated squamous cell carcinoma except 1 adeno-squamous cell carcinoma were proved by histopathology at the primary sites. The external radiation was given by 6~8 MV X-rays and 192 Ir was used for intracavitary brachytherapy. The patients treated by RT alone group received a total dose of 70~86 Gy in 7~9 weeks and that of RB group was 50~70Gy in 5~7 weeks. The dose of brachytherapy ranged 8~24 Gy in 1~3 fractions in 1~3 weeks. Kaplan-Meier and log-rank test were used for evaluating the results of the local control and survival rates in this series. Results:Two patients in the RT group presented resistant disease in the primary site were salvaged by brachytheray. Eight patients had local recurrence (2 in RB, 6 in RT group). The 5-year local control rates were 93.9% in RB group, and 85.2% in the RT group (P > 0.05). The 5-year survival rates were 88.0% and 85.2% in the RB and RT groups (P > 0.05). Three patients developed bleeding in the nasopharynx and all of them died from it. No necrosis of nasopharyngeal mucosa or perforation of soft palate was observed in this series.Conclusion:Both RT and RB groups present a satisfactory 5-year local control and survival rates in this study. Although the 5-year local control rate seems better in the RB group than the RT, no significant difference was observed. The lower dose of external radiation in the RB group may cause milder complication than the higher dose of external radiation without reducing the local control rate. Appropriate brachytheray technique is able to render the treatment safe and effective.

近距离放射治疗是宫颈癌患者根治性放射治疗中必不可少的一部分,然而传统近距离放射治疗的施源器对部分术后残端复发或偏心性或大体积宫颈癌患者存在置入困难、不能适应个体化的局部病灶、剂量分布不理想等问题,继而影响疗效及预后.3D打印技术可以为患者设计个体化的施源器.3D打印技术与近距离放射治疗相结合,可以提高放射治疗的准确性.目前3D打印技术在宫颈癌近距离放射治疗中的应用主要包括构建宫颈癌模型,进行术前规划,显示肿瘤形状以及肿瘤与周围组织的解剖关系.同时还包括制作个性化施源器,减少空气间隙发生,以实现精确剂量分布.此外还包括设计平行/斜行插植针道施源器,优化针道和靶区剂量分布.综述宫颈癌近距离放射治疗中3D打印技术在上述领域的应用现状,讨论开发3D打印所需材料、系统建立及图像引导所面临的挑战.