bolus material
Pronunciation: BOH-lus
Tissue-equivalent material placed on the patient's skin surface to modify radiation dose distribution and improve target coverage.
Full Definition
Bolus material is tissue-equivalent substance (typically gel, wax, or commercial bolus) placed directly on the patient's skin to alter the radiation beam's dose characteristics. Bolus effectively brings the maximum dose closer to the skin surface by eliminating air gaps and providing uniform thickness over irregular body contours. It is commonly used for superficial tumors, chest wall treatments, or when maximum dose delivery to the skin surface is desired. The thickness and composition of bolus material must be carefully selected based on beam energy and treatment goals. Medical editors should understand that bolus use affects dose calculations and skin toxicity expectations, requiring specific documentation in treatment plans and protocols.
Usage
Usage note: Thickness and composition must be specified. Affects dose calculation and skin toxicity.
In Context
- "A 1-cm bolus was applied to ensure adequate dose to the superficial chest wall recurrence." — Treatment setup description
- "The treatment plan specified daily bolus placement for reproducible dose delivery." — Treatment prescription