The RBE for mouse bladders after irradiation with 1 to 8 fractions of d(4) + Be neutrons
Published Online:28 Jan 2014https://doi.org/10.1259/0007-1285-59-697-61
Abstract
Mouse bladders were irradiated with 1, 2, 4 or 8 fractions of electrons or neutrons. Urination frequency was scored from 9 to 14 months after irradiation and this was used as a measure of the extent of bladder damage.
The RBE for neutrons relative to 1.8 MeV electrons increased from 3.2 for large single doses to 5.4 for 8 fractions.
Repair of sublethal injury after electron irradiation was considerable, with 63–72% of each fractionated dose repaired. Repair after neutron irradiation was less, with only 35–43% of each fractionated dose recovered.
Linear-quadratic analysis of all the fractionated bladder data yielded an α/β ratio for electrons of 6–7 Gy and, surprisingly, the α/β ratio for neutrons was only slightly higher at about 8 Gy.
