Figure 4.

Percentage difference in treatment times for single shot treatment from all sectors ((a), (b), (c)) or one sector ((d), (e), (f)) generated with the default setting of the 80 mm radius hemispherical skull model and for the same treatment with discrepancies (1 mm, 2 mm, 3 mm, 5 mm, 10 mm, 15 mm, 20 mm) from 80 mm. C6, C7, and C8 are measurement point of a hemispherical skull measurement helmet and were expanded on above discrepancies. The measurement coordinates ranged from $(\mathrm{x},\mathrm{y},\mathrm{z})=(100\hspace{0.17em}\text{mm},100\hspace{0.17em}\text{mm},125\hspace{0.17em}\text{mm})$ to (100 mm, 40 mm, 125 mm), incremented by $\mathrm{\Delta }\mathrm{y}=20\hspace{0.17em}\text{mm}$. The difference of treatment time increases with increases in skull radius size and distance from center location. One sector was affected significantly larger than all sectors.