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Inverse Planning
• For each IMRT plan the planner may also be expected to
stipulate:
Beam Energy (Usually 6 MV is standard)
Fixed Field or Rotational
Number of beams (Usually 7 or 9 if fixed,)
Number of iterations (attempts)
• TPS then calculates the pattern of beam intensity or
fluence map of the treatment beams through weight
optimisation
• Several modifications of parameters may be needed to
achieve an optimal or best case plan