Validating the clinical use of Breathe Well, a novel breathe monitoring device

Respiratory motion management has become increasingly important in the accurate delivery of radiotherapy. Recently, a novel device, Breathe Well, has been developed, which provides motion management by tracking the movement of external surrogates. This paper has comprehensively assessed the measurement accuracy of Breathe Well in various clinical conditions. The results suggest that the Breathe Well device has good reproducibility, although it demonstrates larger measurement errors in certain setup positions. However, this measurement error becomes trivial if it is setup consistently over the entire course of treatment. For other setup positions, the Breathe Well device can reach a ± 1.0 mm spatial accuracy when the motion amplitude is less than or equal to 20 mm, similar to that of the Varian RPM system. The phase measurement from Breathe Well agrees well with that of the RPM and the QUASAR phantom, indicating that the device has potentials for phase-related clinical applications such as gating.