Gynecologic cancers are often asymmetric, yet current Ir-192 brachytherapy techniques provide only limited radial modulation of the dose. The shielded solutions investigated here solve this by providing the ability to modulate between highly asymmetric and radially symmetric dose distributions at a given location. To find applicator designs that can modulate between full dose and less than 50% dose, at the dimensions of the urethra, a 2D calculation algorithm was developed to narrow down the search space. Two shielding design types were then further investigated using Monte Carlo and Boltzmann-solver dose calculation algorithms. 3D printing techniques using ISO 10993 certified biocompatible plastics and 3D printable tungsten-loaded plastics were tested. It was also found that shadowing effects set by the shape of the shielding cannot be easily modulated out, hence careful design is required. The shielded applicator designs investigated here, allow for reduction of the dose by ov...

中文翻译：

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使用高Z 3D打印敷料器进行强度调制的Ir-192近距离放射治疗

妇科癌症通常是不对称的，但是目前的Ir-192近距离放射治疗技术只能提供有限的剂量径向调节。此处研究的屏蔽解决方案通过提供在给定位置的高度不对称和径向对称剂量分布之间进行调节的能力来解决此问题。为了找到可以在全剂量和小于50％剂量之间调节的喷头设计，在尿道的尺寸上，开发了2D计算算法来缩小搜索空间。然后使用Monte Carlo和Boltzmann-solver剂量计算算法进一步研究了两种屏蔽设计类型。测试了使用ISO 10993认证的生物相容性塑料和3D可打印钨负载塑料的3D打印技术。还发现由屏蔽的形状设置的阴影效果不容易被调制出来，因此需要仔细的设计。此处研究的屏蔽式涂药器设计可减少OV ...