Bloom Lindsey H, Ayala-Peacock Diandra, Venkataraman Rajesh, Eckroate Brett, Sanford Ryan, Chino Junzo, Kim Yongbok, Raffi Julie, Craciunescu Oana
Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, USA.
Eigen Health Services, LLC, Grass Valley, California, USA.
J Appl Clin Med Phys. 2025 Jun;26(6):e70100. doi: 10.1002/acm2.70100. Epub 2025 May 8.
To investigate the feasibility of adapting a commercial prostate biopsy system for transrectal ultrasound (TRUS)-guided hybrid gynecological (GYN) high-dose-rate (HDR) brachytherapy (BT). Leveraging 3D-TRUS and MR image fusion, the prototype system aims to improve real-time needle placement accuracy.
A second-generation, multi-imaging modality female pelvic phantom was developed to validate the system's feasibility. Software and hardware modifications, including user-accessible calibration modules and a redesigned needle guide for multi-needle insertion, were made to the pre-existing commercial system to enable use for GYN BT applications. An end-to-end feasibility test was performed to acquire 3D-TRUS images, perform contour-based registration with pre-implant MR, and insert six needles to targeted locations under real-time TRUS guidance. A 30° tandem without ovoids was added to mimic a hybrid GYN implant. The most proximal and most distal distances between the planned needle track and the visible portion of each inserted needle were measured. A CT/MR image-based treatment plan with a prescribed dose of 6 Gy was generated for the resulting 3D-TRUS-guided implant (tandem and needles) within the phantom.
The modified phantom improved needle visualization and insertion range by de-gassing the silicone and increasing the window size. The system accuracy for average ± standard deviations from intended needle tracks was 1.31 ± 1.36 mm (proximal) and 2.04 ± 2.05 mm (distal). Post-implant imaging confirmed needle placement and good target coverage. Needle placement was verified on CT/MR images and treatment plan quality was clinically acceptable.
With enhanced needle placement accuracy and integrated clinical workflow, this study demonstrates the feasibility of adapting a commercially available prostate biopsy system for 3D-TRUS-guided hybrid GYN HDR BT.
研究将商用前列腺活检系统应用于经直肠超声（TRUS）引导下的混合妇科（GYN）高剂量率（HDR）近距离放射治疗（BT）的可行性。利用三维TRUS和磁共振图像融合技术，该原型系统旨在提高实时针插入精度。
开发了一种第二代多成像模态女性盆腔模型，以验证该系统的可行性。对现有的商用系统进行了软件和硬件修改，包括用户可访问的校准模块和重新设计的用于多针插入的针引导装置，使其能够用于妇科BT应用。进行了端到端可行性测试，以获取三维TRUS图像，与植入前磁共振图像进行基于轮廓的配准，并在实时TRUS引导下将六根针插入目标位置。添加了一个不带卵圆体的30°串联装置，以模拟混合妇科植入物。测量了计划针道与每根插入针可见部分之间的最近端和最远端距离。针对模型内最终的三维TRUS引导植入物（串联装置和针），生成了规定剂量为6 Gy的基于CT/磁共振图像的治疗计划。
改进后的模型通过对硅胶进行除气和增加窗口尺寸，改善了针的可视化和插入范围。系统相对于预期针道的平均±标准差精度为近端1.31±1.36 mm，远端2.04±2.05 mm。植入后成像确认了针的放置和良好的靶区覆盖。在CT/磁共振图像上验证了针的放置，治疗计划质量在临床上是可接受的。
本研究通过提高针插入精度和整合临床工作流程，证明了将商用前列腺活检系统应用于三维TRUS引导的混合妇科HDR BT的可行性。
