Figure 8.

Simulated absorbed dose (a) and equivalent dose using ω_n=10 (b) for active scanning with and without a range shifter. The medulloblastoma field is used for this comparison and the range shifter is Lucite with 7 cm water-equivalent thickness. At 10–20 cm from the field edge, the range shifter increases the out-of-field absorbed dose and equivalent dose by factors of 2–5. Error bars represent 1 standard deviation of the mean from 20 independent simulations and data points are offset slightly for clarity.