Department of Radiation Oncology, Rutgers University, New Brunswick, New Jersey, USA.
Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, USA.
J Appl Clin Med Phys. 2023 Oct;24(10):e14075. doi: 10.1002/acm2.14075. Epub 2023 Jun 19.
To design, manufacture, and validate a female pelvic phantom for multi-modality imaging (CT, MRI, US) to benchmark a commercial needle tracking system with application in HDR gynecological (GYN) interstitial procedures.
A GYN needle-tracking phantom was designed using CAD software to model an average uterus from a previous patient study, a vaginal canal from speculum dimensions, and a rectum to accommodate a transrectal ultrasound (TRUS) probe. A target volume (CTV ) was designed as an extension from the cervix-uterus complex. Negative space molds were created from modeled anatomy and 3D printed. Silicone was used to cast the anatomy molds. A 3D printed box was constructed to house the manufactured anatomy for structural integrity and to accommodate the insertion of a speculum, tandem, needles, and TRUS probe. The phantom was CT-imaged to identify potential imperfections that might impact US visualization. Free-hand TRUS was used to guide interstitial needles into the phantom. The commercial tracking system was used to generate a 3D US volume. After insertion, the phantom was imaged with CT and MR and the uterus and CTV dimensions were verified against the CAD model.
RESULTS/CONCLUSIONS: The manufactured phantom allows for accurate visualization with multiple imaging modalities and is conducive to applicator and needle insertion. The phantom dimensions from the CAD model were verified with those from each imaging modality. The phantom is low cost and can be reproducibly manufactured with the 3D printing and molding processes. Our initial experiments demonstrate the ability to integrate the phantom with a commercial tracking system for future needle tracking validation studies.
设计、制造和验证一种用于多模态成像（CT、MRI、US）的女性盆腔体模，以基准应用于 HDR 妇科（GYN）间质手术的商业针跟踪系统。
使用 CAD 软件设计了一种 GYN 针跟踪体模，以模拟来自先前患者研究的平均子宫、窥器尺寸的阴道管以及容纳经直肠超声（TRUS）探头的直肠。靶区（CTV）设计为从宫颈-子宫复合体延伸。从建模解剖结构创建负空间模具，并进行 3D 打印。使用硅橡胶浇铸解剖模具。构建了一个 3D 打印盒，用于存放制造的解剖结构，以保持结构完整性，并容纳窥器、尾管、针和 TRUS 探头的插入。对体模进行 CT 成像，以确定可能影响 US 可视化的潜在缺陷。使用自由手 TRUS 引导间质针插入体模。商业跟踪系统用于生成 3D US 体积。插入后，用 CT 和 MR 对体模进行成像，并将子宫和 CTV 尺寸与 CAD 模型进行验证。
结果/结论：制造的体模允许通过多种成像模式进行准确可视化，并且有利于施源器和针的插入。从 CAD 模型获得的体模尺寸与每种成像模式的尺寸一致。体模成本低，并且可以通过 3D 打印和成型工艺重复制造。我们的初步实验表明，该体模能够与商业跟踪系统集成，用于未来的针跟踪验证研究。
