Abstract:
:The aim of this work is to evaluate dosimetric accuracy of a new treatment modality, HybridArc, in iPlan RT Dose 4.5 (BrainLAB, Feldkirchen, Germany) using a four-dimensional diode array (ArcCHECK, Sun Nuclear Corporation, Melbourne, USA). HybridArc is able to enhance dynamic conformal arcs with inversely planned elements. HybridArc plans for various sites (intracranial and extracranial) were constructed and after that these plans were recalculated for the ArcCHECK diode array with Monte Carlo (MC) and Pencil Beam (PB) dose algorithms in iPlan RT Dose. All measurements of these HybridArc plans were performed with 6 MV photon beams of a Novalis accelerator (BrainLAB, Feldkirchen, Germany) using the ArcCHECK device without and with an insert containing an ionization chamber. Comparison of the absolute dose distributions measured and calculated in iPlan RT Dose with the MC algorithm at the cylinder of the ArcCHECK diode array for HybridArc plans gives good agreement, even for the 2% dose difference and 2 mm distance-to-agreement criteria. The PB calculations significantly differ from the ArcCHECK measurements so that the MC algorithm is found to be superior to the PB algorithm in the calculation of the HybridArc plans. One of the drawbacks of the PB calculations in iPlan RT Dose is the too large arc step size of 10°. Use of a finer angular resolution may improve the PB results significantly.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Petoukhova AL,van Egmond J,Eenink MG,Wiggenraad RG,van Santvoort JPdoi
10.1088/0031-9155/56/16/021subject
Has Abstractpub_date
2011-08-21 00:00:00pages
5411-28issue
16eissn
0031-9155issn
1361-6560pii
S0031-9155(11)79031-5journal_volume
56pub_type
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