Table 1.
Fields used to create the 3-D dose distributions used in this study. The lateral extent of the fields was 10×10 cm2 and the lateral spacing between the centers of adjacent spots at the isocenter plane was 0.5 cm. dprox: Location of the 90% proximal dose level relative to the Bragg peak dose; ddis: Location of the 90% distal dose level relative to the Bragg peak dose; Eprox: Lowest pencil beam energy; and Edis: Highest pencil beam energy.
| Field | Energy layers | dprox (cm) | ddis (cm) | Eprox (MeV) | Edis (MeV) |
|---|---|---|---|---|---|
| F1 | 36 | 4.0 | 8.1 | 72.5 | 105.2 |
| F2 | 19 | 8.1 | 12.1 | 105.2 | 131.0 |
| F3 | 29 | 10.5 | 20.5 | 121.2 | 176.2 |
| F4 | 19 | 20.5 | 30.6 | 176.2 | 221.8 |