Wedge¶

In German "Keil", assymetric block that can be brought between radiation source and patient to change the intensity of the beam (modify the dose distribution). At the thick parts of the wedge, less radiation can pass the wedge, so the tissue of the patient below those parts do not get the full radiation. At the thin parts, only a small amount of radiation is absorbed by the wedge. See also the schematic drawing here.

There are also so-called "dynamic wedges", where two movable blocks at each side form a configurable gap which can be reconfigured during treatment.