Superior sagittal sinus
The superior sagittal sinus (also superior longitudinal sinus, Latin: sinus sagittalis superior) is an unpaired dural venous sinus running along the attached margin of the falx cerebri.
The superior sagittal sinus arises near the crista galli, passes in the sagittal sulcus, which is a groove on the internal surface of the frontal, parietal, and squamous parts of the occipital bone. Further, the superior sagittal sinus enters the confluence of sinuses at the internal occipital protuberance.
The superior sagittal sinus is triangular in cross-section. At the beginning it is narrow. As it passes posteriorly, the sinus widens gradually.
Situated on either side of the superior sagittal sinus are two or three lacunae, enlarged venous spaces: frontal (small), parietal (large) and occipital (intermediate) lacunae. These lacunae tend to fuse together in the elderly, thereby creating a single elongated lacuna on each side. These lacunae drain diploic and meningeal veins.
The superior sagittal sinus receives many tributaries from the brain: from the cortical veins of the superior part of the frontal, parietal and occipital lobes, from the anterior part of the orbital surface of the frontal lobe, superior cerebral veins, veins from the diploe and dura mater, and veins from the pericranium.