Dose Course 2018_Flipping book

Dose modelling dose in small & composite fields Other aspects of modelling treat ent planning systems (TPS) affecting dose calculations in small photon fields

Aspects of beam modelling on treatment planning systems (TPS) that play major role on the calculation of dose in plans comprising of small MV photon beams:

• finite size of beam source (also referred to as focal spot ) • jaw and MLC leaf edges • resolution: choice of pixel/voxel sizes in fluence and dose matrixes • Inhomogeneities

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