Emissary vein

Emissary vein

Emissary veins as depicted in Gray's Anatomy

The emissary vein is a part of the human circulatory system that connects the dural venous sinuses with veins outside the skull. These veins are named for their function as 'emissaries' that allow blood to flow in and out of the skull, providing a cooling mechanism for the brain.

Structure

Emissary veins are valveless veins that traverse the skull or exit through the foramen, connecting the dural venous sinuses with veins outside the skull. They are located in several areas, including the mastoid, occipital, parietal, and condylar regions.

Function

The primary function of the emissary veins is to provide a route for blood to flow in and out of the skull, which can help cool the brain. They also provide a potential pathway for the spread of infection from the face and scalp to the intracranial structures.

Clinical significance

Due to their valveless nature, emissary veins can potentially allow the spread of infection from the extracranial to intracranial structures, leading to conditions such as cavernous sinus thrombosis and meningitis. They can also be a route for the spread of metastatic cancer.

See also

• Vein
• Dural venous sinuses
• Cavernous sinus thrombosis
• Meningitis