Schematic overview of the 3-D dose reconstruction model.
Depth dose curves, normalized at depth, of the reconstructed (3-D Rec) and the planned dose distribution using the two algorithms of the planning system (FFTC and MGS) compared to the measured dose distribution using film. Depth dose curves are shown for 6 and photon beams and two field sizes; i.e., and .
Calculated, reconstructed, and measured dose distributions and gamma evaluations for a film plane inside the thorax phantom for the 3-D conformal plan. The figure represents data in a plane caudally from the isocenter plane. Isodose lines are plotted in the upper row for 5%, 50%, and 80% of the maximum dose. For the gamma evaluation a dose criterion of 3% of the maximum dose and a distance criterion of is used. The dashed white line indicates the 50% isodose line.
Results of the IMRT plan delivered to the thorax phantom. Isodose lines for 20%, 40%, 60%, 70%, and 90% of the maximum dose are shown. The bottom row shows the gamma evaluation indicating that the film size does not cover the total phantom and the edges are not taken into account during the gamma evaluation.
Extracted energy fluence distributions of the head and neck IMRT plan 1.
Dose distribution, gamma plots, and gamma histograms in a plane located at from the isocenter, for the head and neck phantom of plan 1. Isodose lines are shown for the 50%, 60%, 70%, and 80% of dose maximum. The gamma histograms are calculated over the area within the 5% isodose line excluding the air cavity, with a 3% of the maximum dose criterion and a distance-to-agreement criterion.
Analysis of gamma values of the comparison between the various dose calculation methods and the film measurements for the 3-D conformal plan and the IMRT plan delivered to the thorax phantom. Results are expressed as the average values with their standard deviation (SD). [Note: Acceptance criteria according to Stock et al. (Ref. 31). Bold numbers indicate nonacceptable values: or . Italic numbers fall in the intermediate range, i.e., acceptable if other verification tools indicate no large errors: or .]
Analysis of gamma values of the comparison between the various dose calculation methods and the film measurements for both plans delivered to the head and neck phantom. Results are expressed as the average and standard deviation (SD) of the four films of plan 1, and as the individual values for the two film measurements of plan 2.
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