DIFFERENCE BETWEEN RADIOTHERAPY QUALITY ASSURANCE DEVICES (ARC- AND MAP-CHECKS)

The radiotherapy is a complex procedure and involves understanding of the principles of medical physics, radiobiology, radiation safety, dosimetry, radiation treatment planning, simulation and interaction of radiation with other treatment modalities. Each step in the integrated process of RT needs quality control and quality assurance to prevent errors and to give high confidence that patients will receive the prescribed treatment correctly. A patient-specific quality assurance program has been developed to facilitate the clinical implementation of the intensity-modulated radiotherapy delivered using a micro‐multileaf collimator. The methodology includes several dosimetric tasks that are performed prior to the treatment of each patient. Film dosimeter is performed for each individual field and the multifield composite plan. Individual field measurements are performed at a depth of 5 cm in a water equivalent slab phantom. The heterogeneity inserts of phantom are 2 cm×2 cm×22 cm with absorption characteristics of water, brain, muscle, lung, breast, adipose tissue, bone, and liver.