MotionSim Use Cases
Use Case 1: Commission a gating system
A non-gated delivery is delivered to an in-motion MapCHECK which is driven by a pre-selected motion kernel. A duty cycle is then defined for the gated beam and the same dose is delivered to the in-motion MapCHECK. The non-gated delivery should yield a blurry motion with a poor comparison to the TPS, whereas the gated results should be significantly more desirable if the system is functioning correctly.
Use Case 2: Dose QA for moving targets (with gating)
Prescription dose to the target (PTV) can be compromised due to the effect of internal target motion. The PTV travels along a motion path which defines the internal target volume (ITV.) MotionSim XY/4D simulates the ITV, so that true dose to the PTV can be assessed. PTV dose may appear to pass with stationary QA, however adding MotionSim XY/4D provides true ITV motion, and the confidence to be sure.
Use Case 3: Access interplay effects in MLC-based IMRT
Determining the “interplay effect” in MLC-based IMRT is significant for a given patient plan and target motion. Not taking the interplay effect into consideration during treatment can lead to significant non-uniform fracton-to-fraction dose delivery to the target, further putting the integrity of delivery at risk. The MotionSim XY/4D can be used to assess the interplay effect by comparing gated and non-gated fraction-to-fraction results against the TPS to determine delivery variances.