Imaging for early stage breast cancer

Optimization methods in HDR/PDR BT

1 . No optimization (Paris Dosimetry System) • uniform dwell times

2. Forward optimization • manual optimization (editing dwell times/weights) • geometrical optimization (on distance and volume) • polynomial optimization on - distance dose points (dwell time gradient restrictions) - volume dose points (SSDS – extension of PDS) - dose points on the target surface (conformal) • graphical optimization (only for local adjusments)

3. Inverse optimization (IPSA, HIPO) • anatomy based with surface and volume dose objectives