First-in-human trial using mixed-reality visualization for patient setup during breast or chest wall radiotherapy

Area of Science:

• Medical Physics
• Radiotherapy Technology
• Clinical Trials

Background:

• Assessing the feasibility of mixed-reality (MixR) visualization for patient positioning in breast and chest wall radiotherapy.
• Conducting a first-in-human clinical trial to compare MixR with traditional 3-point alignment techniques.

Purpose of the Study:

• To evaluate the clinical feasibility and accuracy of mixed-reality (MixR) visualization for patient setup in breast and chest wall radiotherapy.
• To compare the performance of MixR visualization against a standard 3-point alignment method in a real-world clinical setting.

Main Methods:

• A first-in-human clinical trial involving 18 patients (10 proton, 8 photon RT) for breast or chest wall treatments.
• Each patient received MixR visualization for five fractions and 3-point alignment for five fractions, with alignment accuracy assessed via cone-beam CT and kV/kV imaging.
• Registration time and image-guided radiotherapy (IGRT) utilization were recorded during the setup process.

Main Results:

• In proton therapy, mean 3D shifts were 0.96 cm (3-point) and 1.18 cm (MixR), with equivalence demonstrated (<0.5 cm difference).
• In photon therapy, mean 3D shifts were 1.18 cm (3-point) and 1.00 cm (MixR), with equivalence demonstrated (<0.3 cm difference).
• Minor variations were observed in registration time and IGRT use between the two methods.

Conclusions:

• Mixed-reality (MixR) visualization is a feasible option for patient setup in breast cancer radiotherapy, achieving accuracy and efficiency comparable to 3-point alignment.
• Further advancements in marker tracking, feedback mechanisms, and understanding perceptual challenges are necessary for MixR to match the accuracy of modern surface-guided radiotherapy (SGRT) systems.