Computational validation of the stereology principle applied to the microdosimetry of boron neutron capture therapy

High resolution quantitative autoradiography (HRQAR) is a novel technique t hat has been developed in our laboratory and applied to the microdosimetry of boron neutron capture therapy (BNCT). High resolution quantitative autor adiography is employed to define the microdistribution of boron-10 atoms wi thin a 1-2 mu m frozen tissue section. This microdistribution is used as in put to a novel two-dimensional Monte Carlo charged particle transport calcu lation that computes various microdosimetric parameters, such as the number of nuclear ''hits,'' energy absorbed in the nuclei, etc., within the envir onment of actual tissue morphology (i.e., cell nuclei, cytoplasm, and intra cellular space). Stereological transformation is then implemented to transf orm the two-dimensional calculations into effectively three-dimensional res ults. In the present study no seek to demonstrate the validity of the surro gate two-dimensional 2-D computation as being quantitatively equivalent to a hypothetical full 3-D calculation. The results show that within the limit ations of the test parameters used the surrogate 2-D and 3-D results are co mpletely equivalent within the statistical constraints of the Monte Carlo c alculations. Limitations of this approach also are evaluated, including a M onte Carlo calculation of the influence of the thickness of the histologica l tissue section and the track detector and the influence of He-4 and Li-7 particle lateral and range straggling. (C) 2000 American Association of Phy sicists in Medicine. [S0094-2405(00)01303-1].