Commissioning and Clinical Evaluation of a Secondary Check Software for 3D Conformal and IMRT Treatment Plans
P Foong1, H Looe2, B Poppe3*, (1) ,,,(2) ,,,(3) WG Medical Radiation Physics Pius-Hospital & Carl von Ossietzky Universität, Oldenburg,SU-E-T-544 Sunday 3:00:00 PM - 6:00:00 PM Room: Exhibit Hall
The increasing complexities of the geometry of 3D radiation treatment plans possess challenges
to the monitor unit (MU) and dose verification in clinical routine. In this work, the commissioning
of the DIAMOND software (PTW-Freiburg Germany) for two Siemens linear accelerators
(Primus & Artiste) along with the evaluation of its performance is described.
DIAMOND employs the modified Clarkson integration method for dose computation and a pointeye-
view (PEV) method for scatter calculation on collimators by a geometrical back-projecting
into the collimation system from the view of the source. During the commissioning process, the
machine data (geometrical set up) and dosimetry base data such as the percentage depth dose
(PDD), head scatter factor Sc as well as total scatter factor Sc,p, off-axis profiles are entered into the software. A comprehensive validation process is performed following the provided protocol.
For evaluation purposes, twelve 3D conformal treatment plans and two prostate IMRT plans are
calculated with DIAMOND and the results are compared to the values from the treatment
planning system (TPS).
The deviations of the MU for 3D conformal treatment plans computed with the DIAMOND
software are within ±3%. For IMRT plan verification, the dose at a point in the target volume is
computed for every treatment beam, with deviations within 0.40% to 3.28%. The typical time for
single dose point verification is less than a minute, thus minimizing the clinical workload of the
verification process. For dose matrices calculation at certain plane, a relative longer
computation time is needed depending on a field dimension.
In this work, we have demonstrated the ability of the DIAMOND software to compute MU and
dose at a point for 3D conformal and IMRT plans. Its speed and accuracy implies that
DIAMOND can be implemented as independent secondary check software in the clinical routine.