ABSTRACT
This chapter provides an overview of measurement- and calculation-based techniques for patient-specific pretreatment quality assurance (QA) that provide multidimensional dose information, ideally in "full" three dimension. The challenge at the department level is to setup an effective net of QA procedures, since the goal of a routine pretreatment verification procedure is to catch errors before the actual treatment begins. The main limitation of the treatment-planning system is that it provides a model of the patient and plan delivery and is only as good as the input data for the dose calculation algorithms, and therefore there are limits to the modeling capability. Calculation-based methods and verification of dose and monitor units (MU) for conventional three dimensional conformal radiation therapy techniques have been used for a long time as routine QA procedures. When used as a general dose verification tool, without the expectation that small deviations will be detected, independent dose and MU verification can be of great value in a department.
