For each of the 10 scheduled IMRT dose distributions, 440 delayed doses were generated by combinations of spatial doses (range, 0-10 mm with a 0.5 mm increment) and dose carry-overs (range, 0-10% with a 0.5% increment), as shown in Figure 3a.3a. Maps γ planar dose distributions of IMRT, with criteria of 3 mm/3%, were established between each of the staggered distributions, with or without noise, and the initial dose distribution; The percentage of passages (percentage of pixels with γ 3 mm (an overlay of 10 cases). There were 678 staggered distributions that filled P (3 mm, 3%) ≥ 90% or “passed” imRT-QA, but 328 (48%) of them had changes (d0) > 3 mm. Figure 88 shows an example of the passport percentage usage limits for IMRT QA. Figure 8a8a shows the initial dose distribution with that shown in Figure 1a.1a. Figure 8b8b is the dose distribution with a spatial displacement of 4.5 mm. Figures 8c, 8c, 8d8d show absolute DD and DTA respectively.
Figure 8e8e shows the gradient map of the dose distribution and Figure 8f8f shows the surface distance between the initial distribution and the offset distribution of the dose. For this example (spatial displacement of 4.5 mm), the D90 was 3 mm and the percentage of pass (percentage of pixels with γ < 1) for the criteria of 3 mm/3% was 90.01%. This result also shows that the percentage of successful people may not reflect the difference between two doses and therefore should not be used for quantitative analysis. Conclusions: Surface distance is a direct measure of the difference between two doses and can be used to evaluate or determine parameters for the calculation of the γ index. . . .