Comparative analysis of intensity modulation inverse planning modules of three commercial treatment planning systems applied to head and neck tumour model.

摘要: Abstract Background and purpose : Three commercial treatment planning modules for intensity modulated radiation therapy (IMRT) Inverse Planning, MDS-Nordion Helax-TMS, Varian Cadplan-Helios, CMS Focus, were compared in an attempt to determine potential application limits or dosimetric differences among various optimisation algorithms. Materials methods A comparative analysis of dose distributions was conducted at level on a group four patients presenting advanced head neck cancers. In the study, we analysed primarily static ‘step shoot' multileaf implementation modulation realisation with some investigation, Cadplan-Helios ‘sliding window', dynamic approach IMRT delivery. The whole study carried out using inverse tools implemented by vendors fully optimising each plan obtain best dosimetry given general objectives. To achieve adequate target coverage, Helax-TMS Focus adding extra margins 5 6mm volume (PTV). Beam arrangements set five nine equally spaced fields. two complexity levels. At first level, dose–volume constraints applied only spinal cord, while parotid glands added second level. relative values histograms compared, together estimate biological implications terms Equivalent Uniform Dose target. system also number levels selected discretisation fluence matrix investigated. Results With common strategies proper consideration (TPS) specific features (e.g. PTV margin problem), no substantial three algorithms demonstrated cord. outlined where sub-optimal results obtained 5-field geometry. Mainly due volumes, presented significant better sparing healthy tissue around PTV, mean Irradiated Volume 50% Finally, dosimetrically acceptable stable target, minimum eight should be collimator (MLC) segmentation, giving average 1.5 segments per field Conclusions TPS show instance that analysed, as well conversion from computed fluences sequences systems can produce substantially equivalent plans (for coverage organs risk sparing) if is performed once strong understanding feature achieved. Secondly, limited (about eight)