Bragg Peak

When energetic protons enter tissue, they release most of their energy as they come to rest—at the site of the tumor. Immediately after the peak of energy release, or the "Bragg Peak," the radiation dose falls near zero. Less radiation affects healthy tissue in front of the tumor, and virtually none of it affects healthy tissue behind the tumor. This results in far less damage to nearby organs and structures. Because the healthy tissue receives less radiation, higher doses may be delivered to the tumor more accurately, leading to more effective treatment.