Where should a missing tissue compensator be placed when used?

When using a missing tissue compensator in radiation therapy, it should be placed at some distance away from the skin to effectively account for the irregularities in contour that might affect dose distribution. Positioning the compensator at this distance allows for the compensator to modify the radiation beam more appropriately by blending the delivered radiation dose with the surrounding tissue absorption characteristics.

Placing the compensator directly on the skin may lead to inaccuracies in dose delivery, as it would not account for the necessary scattering and buildup required for effective treatment. Positioning it on the end of the electron cone could introduce additional complexities regarding dose distribution and is not standard practice. Additionally, placing the compensator on top of the bolus material at isocenter does not allow for the proper use of the missing tissue compensator to modify deep tissue doses effectively.

Consequently, maintaining a distance from the skin enhances the compensator’s role in achieving the desired therapeutic effect while staying compliant with radiation therapy principles.