Straight sinus

A major venous channel located within the cranial cavity.

The straight sinus is a large venous channel situated within the brain that plays a critical role in draining blood from various regions. It is formed by the union of the inferior sagittal sinus and the great cerebral vein (vein of Galen). This sinus runs along the line where the falx cerebri and the tentorium cerebelli meet.

Terminologia Anatomica

sinu-rectus

System

Circulatory system

Function

The primary function of the straight sinus is to collect venous blood from deep structures of the brain and transport it to the confluence of sinuses, where it can then proceed to the internal jugular veins. By draining blood from areas such as the midbrain and parts of the cerebellum, the straight sinus helps maintain proper venous circulation within the cranial cavity. Additionally, it plays a role in regulating intracranial pressure and facilitating the removal of metabolic waste products, ensuring brain tissues remain healthy and functioning optimally. Any obstruction in this sinus can potentially lead to serious complications, underscoring its importance in cerebral circulation.

Location

The straight sinus is anatomically positioned near the midline of the cranial cavity, bordering the falx cerebri and tentorium cerebelli, which are two important membranes in the brain. It is found at the junction where the inferior sagittal sinus drains into it from below, and the great cerebral vein contributes to it from the front. This sinus runs posteriorly and opens into the confluence of sinuses, which is located at the upper part of the occipital bone, allowing for further drainage into other larger venous channels. Its deep location within the brain makes it an important structure for venous drainage and highlights the complex vascular network of the cranium.

Did You Know?

The straight sinus is part of the dural venous sinus system that helps drain deoxygenated blood from the brain.
Despite its name, the straight sinus is not completely straight, but rather has various curves and turns.
It can be involved in various pathologies, including thrombosis, which can severely affect brain function and lead to increased intracranial pressure.