TY  - EJOUR
AU  - Menzel, Miriam
AU  - Axer, Markus
AU  - De Raedt, Hans
AU  - Costantini, Irene
AU  - Silvestri, Ludovico
AU  - Pavone, Francesco S.
AU  - Amunts, Katrin
AU  - Michielsen, Kristel
TI  - Finite-Difference Time-Domain simulations of transmission microscopy enable a better interpretation of 3D nerve fiber architectures in the brain
M1  - FZJ-2019-00285
PY  - 2018
N1  - 15 pages, 6 figures (main part); 18 pages, 13 figures, 2 tables (supplementary information)   	https://arxiv.org/abs/1806.07157
AB  - Transmission microscopy measurements of histological brain sections provide usually only 2D (in-plane) information about the spatial nerve fibre architecture. To access the third dimension (out-of-plane orientation) of the nerve fibres, more advanced techniques are required, such as Three-dimensional Polarized Light Imaging (3D-PLI) which uses birefringence measurements to derive the 3D fibre orientations. Here, we show that the polarization-independent transmitted light intensity (transmittance) already contains 3D information: we demonstrate in experimental studies of multiple species (rodent, monkey, human) that the transmittance decreases significantly (by more than 50 %) with increasing out-of-plane angle of the nerve fibres. Using finite-difference time-domain simulations, we demonstrate that this decrease is mainly caused by polarization-independent light scattering in combination with the finite numerical aperture of the imaging system, and that the transmittance does not depend on the crossing angle between in-plane fibres. This allows to use the transmittance e.g. to distinguish between in-plane crossing and out-of-plane nerve fibres in 3D-PLI measurements.
LB  - PUB:(DE-HGF)25
UR  - https://juser.fz-juelich.de/record/859427
ER  -