Equations for the dose distributions of high-energy electrons.

Dose distributions of high-energy electrons were calculated using simple equations which were derived from experimental data. Equations are composed of functions of the percent depth dose, the field effect ratio and the off-axis ratio. The electron energy and field size are parameters for the calculation. Dose distributions were compared between experiments and calculations for different field sizes and energies. It is concluded that the equations can be applied clinically to calculate dose distributions for treatment planning.