Premium
The influence of heavy water on boron requirements for neutron capture therapy
Author(s) -
Wallace S. A.,
Mathur J. N.,
Allen B. J.
Publication year - 1995
Publication title -
medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.473
H-Index - 180
eISSN - 2473-4209
pISSN - 0094-2405
DOI - 10.1118/1.597585
Subject(s) - boron , neutron capture , neutron , materials science , heavy water , neutron flux , neutron temperature , radiochemistry , penetration (warfare) , nuclear medicine , nuclear engineering , environmental science , nuclear physics , chemistry , medicine , physics , deuterium , operations research , engineering
Neutron penetration in tissue is a major limitation of thermal NCT, as such much work has centered 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 a heterogeneous ellipsoidal 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. Both thermal (0.025 eV) and epithermal (2–7 keV) ideal neutron beams are analyzed. Using 10 B ratios in the range of documented human uptake, the thermal advantage depth improved by approximately 0.7 cm for 20% D 2 O replacement, however, the therapeutic depth increased by less than half this value. For the epithermal beam, both the advantage depth and the therapeutic depth increased by over 1 cm. Effects of heavy water replacement on 10 B requirements to therapeutically treat the midline of the brain are also evaluated.