A new high dose rate (HDR) brachytherapy program was initiated in a community hospital setting, with the goal of using magnetic resonance (MR) images with the implant in place during the planning process. Physics acceptance testing and commissioning was completed for key program components, including multiple applicators. To image new applicators for MRI‐based planning prior to use with patients, agar gel doped with copper sulfate was created using simple, MR‐safe household materials as a practical and inexpensive alternative to custom‐machined precision phantoms. Applicators in‐phantom were scanned in a 1.5 T MRI scanner using the same sequences developed for the brachytherapy program, then rigidly registered to high‐resolution computed tomography (CT) images to assess distortion, artifact, and geometric displacement. To date, Varian tandem and ring sets, segmented cylinders, cervical probes, endometrial applicators; and third‐party plastic needles, tandems, and vaginal guides have been imaged in phantom and are available for use clinically.

中文翻译：

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用于基于 MRI 的 HDR 近距离放射治疗应用器调试的简单模型制造

在社区医院环境中启动了一项新的高剂量率 (HDR) 近距离放射治疗计划，目标是在规划过程中使用植入物的磁共振 (MR) 图像。完成了关键程序组件的物理验收测试和调试，包括多个应用程序。为了在用于患者之前为基于 MRI 的计划成像新的涂药器，使用简单、MR 安全的家用材料制作了掺有硫酸铜的琼脂凝胶，作为定制加工精密体模的实用且廉价的替代品。使用为近距离放射治疗计划开发的相同序列在 1.5 T MRI 扫描仪中扫描幻影中的施药器，然后严格配准到高分辨率计算机断层扫描 (CT) 图像，以评估失真、伪影和几何位移。迄今为止，Varian 串联和环组、分段圆柱体、宫颈探头、子宫内膜涂药器；第三方塑料针、串联和阴道导板已在幻像中成像，可供临床使用。