Design and Construction of a Novel Hemi-Body Tset Fixture Design
Abstract
Purpose
A modernized partial‑body Total Skin Electron Therapy (TSET) frame was designed, constructed, and prepared for commissioning at UW Health Eastpark Medical Center to replace an aging wooden structure and address the absence of commercially available systems meeting required specifications. Project goals included improving therapist ergonomics, enabling modular shielding configurations, ensuring compatibility with multiple treatment rooms, and maintaining compliance with AAPM TG‑30 treatment uniformity guidelines.
Methods
Clinical physicists, radiation oncologists, and Healthcare Technology Management engineers collaborated to define functional and structural requirements. Iterative CAD modeling guided optimization of frame height, wheel geometry, and stability while ensuring the device could pass through treatment room doorways without tipping. The final design incorporated a full‑height aluminum frame, adjustable patient‑support handles, a spoiler, a tactile HDPE‑strand proprioceptive web, and a modular acrylic shielding system consisting of ten interlocking 15‑cm panels selected for low‑Z properties, transparency, and ease of replacement. Room logistics, storage feasibility, and workflow integration were evaluated across multiple clinical locations. Assembly progress, AlignRT adjustments, and pre‑commissioning QA activities were documented throughout development.
Results
The completed frame met all structural, ergonomic, and workflow requirements. The aluminum base provided sufficient stability to support 1.5 m of acrylic shielding. The device fit through multiple treatment room doorways and could be stored in-room without restricting gantry rotation. Adjustable vertical bars and sliding brackets improved therapist usability. The redesigned tactile web enhanced patient proprioception and minimized patient sway. The final assembled height (212 cm) accommodated most patients up to approximately 6½ feet tall while remaining within TG‑30 vertical uniformity expectations. Full assembly was completed January 19, 2026.
Conclusion
A cost‑effective, modular, and ergonomically optimized partial‑body TSET frame was successfully developed. The design meets structural and clinical workflow needs, supports flexible shielding configurations, and provides a scalable platform for future deployment. Commissioning is underway to enable clinical implementation.