Superior sagittal sinus

The superior sagittal sinus (also called the superior longitudinal sinus, Latin: sinus sagittalis superior) is an unpaired dural venous sinus that runs along the attached margin of the falx cerebri. It collects venous blood from the anterolateral parts of the cerebral hemispheres and drains into the confluence of sinuses.

The superior sagittal sinus arises near the crista galli and passes in the sagittal sulcus - 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 superior sagittal 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. Diploic and meningeal veins drain into the mentioned lacunae.

The superior sagittal sinus receives many tributaries from the brain. It receives from the cortical veins of the superior part of the frontal, parietal and occipital lobes, and of the anterior part of the frontal lobe's orbital surface, superior cerebral veins, veins from the diploe (diploic veins) and dura mater (meningeal veins), as well as veins from the pericranium.