Automated range compensation for proton therapy.

A system has been developed to produce complex three-dimensional Lucite compensators to adjust proton depth of penetration within treatment fields. Range adjustments are based on depth prescription contours laid on serial CT scans which contain detailed information on patient contours and inhomogeneities traversed by the beam. The automated system for range compensator production is described, with the constraints arising from proton scattering, fabrication time, and required resolution. Agreement between desired and obtained dose distributions is shown for a typical treatment site. The system's use for automated production of contoured patient apertures is also discussed.