Corpus: Superior sagittal sinus

The superior sagittal sinus is an intradural venous blood vessel (sinus of the dura mater) that runs along the upper edge of the longitudinal cerebral fissure.

The superior sagittal sinus has a triangular cross-section, with the roof formed by the outer layer of the dura mater. The two side walls are created by the inward-folding layers of the falx cerebri, which is a dublication of the meningeal layer of the dura mater.

Within the bony skullcap (calvaria), the superior sagittal sinus occupies the median superior sagittal sulcus and features lateral extensions known as venous lacunae.

The superior sagittal sinus primarily drains the superficial veins of the brain, specifically the superior cerebral veins, which connect to the sinus via intradural bridging veins. Its drainage area includes the upper parts of the medial and lateral cerebral cortex of the frontal, parietal, and occipital lobes. It is also connected to the superficial cerebral vein through the superior anastomotic vein (Trolard vein).

Venous blood from the superior sagittal sinus flows into the confluence of sinuses via the transverse sinus and sigmoid sinus into the internal jugular vein. The superior sagittal sinus also plays a role in cerebrospinal fluid (CSF) resorption through arachnoid granulation.

Obstruction of the superior sagittal sinus, due to conditions such as septic or aseptic sinus thrombosis or compression by a meningioma, can lead to outflow disturbances. This can result in cerebral edema, congestion-induced hemorrhages, and associated central nervous system deficits.