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Limitations of “basic calculations”
Patients are NOT water phantoms
Patient contour:
•
beam may be obliquely incident onto the patient
•
patient surface may be curved or of irregular shape
•
Heterogeneities:
•
tissues, such as lung and bone, have densities that
differ considerably from that of water.
Limitations will be looked at in
“Calculation of dose distributions in TPS”
Basic Dose Caculation
Principles 2012
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