SU‐E‐T‐404: The Effect of Field/target Size on Quality Assurance of TomoTherapy IMRT Treatments When Using a Diode Array for Absolute and Relative Dose Measurements

Purpose: Despite the known energy sensitivity of diodes due to an over‐ response to low‐energy photons, the presence of which depends on field size, there is trend toward using diode arrays for performing dose measurements in IMRT QA. The purpose of this investigation is to quantify the dependence of diode array dose measurements on field/target size, assess machine output tracking abilities, and improve the accuracy of diode arrays …