The purpose of this study was to quantify and map the gross
fibre architecture of the cranial dura mater
(CDM) using small angle light scattering (SALS). In SALS, HeNe laser light
is passed through the tissue,
and the resultant scattering pattern is analysed to determine the preferred
fibre direction and degree of
orientation. The dura mater was found to be a complex structure with
fibre orientations ranging from highly
aligned to nearly random. In the temporal region, 80% of the samples (n=20)
were found to have regions
composed of highly oriented fibres with a mean fibre direction of
6.3°±0.8° with respect to the sagittal
plane (i.e. almost parallel to the superior sagittal sinus). These highly
aligned regions were found in
symmetric anatomical locations about the median sagittal sinus and had
similar fibre orientations over both
hemispheres. Although our sample size was small, we found that the size
of the symmetric regions, which
covered 14.4±1.6% of the total CDM area, was not influenced by
subject's age or sex. The presence of
these highly oriented fibre regions in CDM may be due to mechanical
forces exerted on dura mater during
its development. These forces may have induced realignment of the collagen
fibres in the direction of tensile
pull, although the exact basis for the unique gross fibre architecture
of
CDM remains unknown.