IMRT

Intrafraction movement in lung • Dosimetric effects are linked to the relative frequencies of all the movements. • There seems to be a possible problem with leaf/ movement interplay in DMLC techniques (VMAT/ DMLC) which can not be solved by PTV-margins. • The size of this effect is dependent on the relative movement (size and speed). • VMAT : depending on whatever your leaves are doing (can have low modulation) • Possible solutions can be found in tracking, gating ...