A thermoplastic bolus material can be used to alter the depth of the maximum radiation dose (Dmax) during radiation therapy. It is a tissue-equivalent material, which means that it has similar properties to human tissue when it is irradiated.
During radiotherapy, the radiation dose usually “builds up” a couple of millimetres beneath the skin, instead of directly underneath it (the depth depends on the beam-energy). When treating conditions like skin cancer, you may want to alter the beam, so that the maximum dose can be located right underneath the skin, where it is most needed in this instance. The bolus material will serve as a “build-up material” and can help you to achieve just that.
The diagram below is an example for bolus use in Electron Beam Therapy. The orange region is the tumour, where you want the “build-up dose” to be deposited.
Thermoplastic bolus materials from Orfit are available in sheets of different sizes and in pellets. The latter is especially useful for filling up cavities, such as the ear.
Take a look at the available sizes and find more detailed instructions on how to use Orfit Thermoplastic Bolus in the Instructions for use.