Vena emissaria

Vena Emissaria is a small vein that connects the dural venous sinuses with veins outside the skull. These veins are unique in that they do not possess valves, which are typically present in other veins of the body. The vena emissaria plays a crucial role in the circulatory system, particularly in the drainage of the cranial cavity.

Anatomy

The vena emissaria is located within the human skull. It serves as a connection between the dural venous sinuses, which are venous channels found between layers of dura mater, and the veins outside the skull. There are several types of vena emissaria, including the mastoid emissary vein, the occipital emissary vein, and the parietal emissary vein, each named for the area of the skull in which they are located.

Function

The primary function of the vena emissaria is to drain blood from the cranial cavity to veins outside the skull. This is particularly important in regulating intracranial pressure, as the drainage of blood helps to maintain a balance within the cranial cavity.

The vena emissaria also plays a role in the body's thermoregulatory processes. It helps to dissipate heat from the brain by allowing blood to flow from the warmer interior of the skull to the cooler exterior.

Clinical Significance

Due to their unique structure and location, the vena emissaria can sometimes serve as a pathway for infections to spread from the face and scalp to the intracranial structures. This can potentially lead to serious conditions such as cavernous sinus thrombosis or meningitis.

See Also

• Vein
• Dural venous sinuses
• Cranial cavity
• Circulatory system