A pre-absorber optimization technique for pencil beam scanning proton therapy treatments

In pencil beam scanning proton therapy treatments is possible to treat almost all tumors without using any passive object on the beamline. The only parameter that forces to use a passive beam modifier is the minimum energy. Usually the minimum energy is either 70 or 100  MeV [1], corresponding to 4.1 cm or 7.5 cm of water equivalent thickness, respectively [1]. This means that, for minimum energies available of 70 MeV, tumors located at a water equivalent depth shallower than 4 cm cannot be treated if a pre-absorber is not used.
Source: Physica Medica: European Journal of Medical Physics - Category: General Medicine Authors: Tags: Original paper Source Type: research