Poster — Thurs Eve‐26: Influence of MLC leaf edge and tongue and groove effect on IMRT dose distributions

An important consideration when using multileaf collimators (MLCs) for IMRT delivery is the correct account of leaf edge effects. To study these effects, two maps were constructed from a clinical beam's step and shoot delivery sequence: a time-weighted leaf edge position (LEP) map where the pixel intensity was proportional to the length of time that a leaf edge defined the edge of any segment within the field, and a (TG) map where pixel …