Bolus is a special substance used as equivalent to the tissues of the human body in radiotherapy, meaning that when it’s exposed to radiation, its features would be similar to those of the human tissue. One of the features of the high-voltage beams used in radiotherapy is that the rays delivered by the aforementioned beams reach their maximum level in a few millimeters under the skin instead of the surface of the patient’s skin.
In case of skin cancers or any concern about possible complications of surgical scars, which is aimed to deliver the radiation to the skin, the goal would be maximizing the amount of this radiation. In these conditions, the bolus functions as a substance equivalent to the additional tissue on the skin, increasing the amount of radiation. The thickness of these materials will vary for different patients and different photon energy and electron beams. The RTE boluses are presented with thicknesses of 5 and 10 mm and in different dimensions.
