ABSTRACT
Helical TomoTherapy delivers intensity-modulated treatments through a unique architecture that resembles to a computed tomography (CT) scanner. The CT-like design of the TomoTherapy system enables the acquisition of CT images with a mega-voltage (MV) fan beam and the patient in treatment position. Films can be directly calibrated in the TomoTherapy beam quality. However, the specificities of the TomoTherapy technology make this procedure less practical than with a C-arm Linac. M. Avanzo et al. measured the skin dose delivered by the TomoTherapy system using EBT films. In general, they observed an overestimation of the dose at the skin by the TomoTherapy treatment planning system. Radiographic films were used in general. But the procedures described can be readily adapted to General Aniline & Film (GAF) chromic films, especially mechanical tests that typically do not rely on the quantification of the optical density into dosimetric quantities. GAFchromic films are well suited for TomoTherapy devices.
