The Superior Sagittal Sinus (SSS) runs along the top
of the brain. Structures called the Arachnoid
Villi are attached to the SSS and are the main site of reabsorbtion
of cerebrospinal fluid (CSF) back
into the blood. The mechanism whereby the CSF is absorbed into the blood
is the difference in hydrostatic pressure between the two fluids. The arachnoid
villi enlarge with age to form bulb-like granulations. They are covered
by a smooth endothelium that prevents the
veneous blood actually entering the central
nervous system (CNS).
Sagittal Sinus links:
The
superior sagittal venous sinus
Arachnoid
granulations in lateral lacunae of the superior sagittal sinus
T2-weighted
structural MR: Slice 31
Dorsal
view of human brain in meninges
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