The influence of heavy water on boron requirements for neutron capture therapy

Neutron penetration in tissue is a major limitation of thermal NCT, as such much work has centred upon the epithermal neutron beam in an effort to improve this situation. Further gains in neutron flux penetration, and thus therapeutic ratios, are possible if natural water is replaced with heavy water prior to therapy. Applying MCNP to heterogeneous ellopsoidal skull/brain model, advantage depth and therapeutic depth parameters are studied as a function of heavy water replacement for a range of tumor to blood boron ratios.