KEY POINTS
- Feasibility study using a RANDO phantom and 8 healthy participants imaged standing with a Vectra WB360 photogrammetry system for total skin electron therapy dose modelling.
- The photogrammetry system acquired 92 photographs in 3.5 milliseconds, with reconstruction taking approximately 15 minutes per scan.
- Commercial treatment planning system modelling of extended source-to-surface distance total skin electron therapy geometry was unsuccessful; Monte Carlo dose calculation was performed using EGSnrc and Varian TrueBeam 6 MeV electron phase-space data.
- Monte Carlo simulations generally took less than 2 hours per beam, with three-dimensional dose files up to 1.75 GB before summed exports reduced file size by approximately 99%.
- Participant simulations produced a mean total B factor of 2.8 ± 0.1 at the anterior abdomen reference point and broadly reproduced clinically known hot and cold spot patterns, although disagreement remained in several regions including shoulder, lower leg, ankle, and top of foot.
CLINICAL TAKEAWAY
This study suggests that whole-body photogrammetry plus Monte Carlo simulation can provide useful pre-treatment information about total skin electron therapy surface dose homogeneity. The workflow may help anticipate hot spots, cold spots, shielding needs, and boost regions before treatment. But this remains a feasibility workflow, not a routine clinical planning solution: commercial system integration failed for the extended-distance electron geometry, simulations were computationally heavy, and patient treatment validation is still needed.