Abstract
Near-infrared light propagation in various models of the adult head
is analyzed by both time-of-flight measurements and mathematical
prediction. The models consist of three- or four-layered slabs, the
latter incorporating a clear cerebrospinal fluid (CSF) layer. The
most sophisticated model also incorporates slots that imitate sulci
on the brain surface. For each model, the experimentally measured
mean optical path length as a function of source-detector spacing
agrees well with predictions from either a Monte Carlo model or a
finite-element method based on diffusion theory or a hybrid radiosity-diffusion
theory. Light propagation in the adult head is shown to be highly
affected by the presence of the clear CSF layer, and both the optical
path length and the spatial sensitivity profile of the models with
a CSF layer are quite different from those without the CSF layer.
However, the geometry of the sulci and the boundary between the gray
and the white matter have little effect on the detected light distribution.
(C) 1991 Optical Society of America
Users
Please
log in to take part in the discussion (add own reviews or comments).