Proton Pencil Beam Scanning planning/ rayPencilScanning and rayLineScanning
RayStation provides leading tools for designing and optimizing actively scanned pencil beam proton treatment plans, including IMPT, single field uniform dose and distal edge tracking.
RayStation enables design and optimization of proton treatment plans for actively scanned pencil beams, with the option to include block apertures. All optimized plans are directly deliverable since the spot weight limits are taken into account in the optimization loop.
Aperture shape can be created using treat-and-protect ROI with user-defined margins, and manual tools can be used to shape and edit. Accurate dose computation is achieved using the Monte Carlo dose engine, including the block edge scattering effect. Block aperture is taken into account in spot selection and included in dose calculation for optimization (pencil beam or Monte Carlo).
A wide selection of tools for robust optimization makes it possible to create treatment plans that are robust to geometrical and dosimetric uncertainties.In addition, the inclusion of 4D-CT images in the robust optimization process addresses situations where there is significant relative interfractional motion of internal organs, such as in the thorax during free breathing.
Other challenges arising from intrafractional motion include interplay effects, which will occur if the delivery takes place on a similar time scale as the intrafractional organ motion. Evaluation of these effects and methods to mitigate them is crucial, and RaySearch has developed tools for this purpose, such as layer repainting. All plans are directly deliverable after optimization since the minimum spot weight is taken into account in the optimization.
- Ultrafast Monte Carlo dose engine for optimization and final dose
- Pencil beam dose engine
- PBS treatments with block apertures
- Optimization of pencil beam scanning and line beam scanning using multi-field optimization, single field uniform dose tracking techniques.
- 4D optimization
- Robust optimization over multiple 4D-CT images, scenario-based optimization regarding uncertainties in range (density) and position (isocenter shifts, target shifts, etc.)
- Control of initial energy layer and spot selection per beam with respect to target and OAR
- Layer repainting
- Range shifter support
- Bragg peak visualization
PBS specific features:
- Step-and-shoot spot scanning
- Optimization including lower and upper limits of spot MU delivery
- Spot visualization with beam’s-eye-view and patient 2D/3D views
- Manual editing of spot pattern
- Spot weight filtering
- Quasi-discrete PBS
- Spot order sorting through scan path length optimization
Line scanning specific features:
- Line segment visualization
- Line segment filtering in optimization with beam’s-eye-view and patient 2D/3D views