pBolus is used in radiation therapy where a patient requires full prescription dose on the skin surface. The pBolus acts as a tissue equivalent material, placed on the patient skin to account for the build-up region of the treatment beam. There are currently a variety of different Bolus materials in use throughout Australia including thermoplastic sheets, pellets and gel slabs (Superflab).
In general, the aim is that the pBolus will contact well with the patient’s skin resulting in minimal air gaps, be of uniform density and thickness, be reproducible to position and not cause discomfort to the patient in either the creation or daily positioning of the pBolus.
Literature reports that 3D printing allows the fabrication of tissue equivalent pBolus of detailed volumetric structures defined on the CT image data. This results in the possibility for pBolus to be made for complex shapes fitting closely to the patient’s skin in a reproducible fashion.