Diploic veins

Diagram of the diploic veins in the human skull.

The diploic veins are a network of veins located within the diploë, the spongy bone layer between the inner and outer layers of the cranial bones. These veins are responsible for draining blood from the bone marrow and the skull into the venous sinuses of the dura mater.

Anatomy

The diploic veins are situated within the diploë of the cranial bones, which include the frontal bone, parietal bones, temporal bones, and occipital bone. They are characterized by their thin walls and large lumens, which allow them to accommodate changes in blood volume.

Major Diploic Veins

The major diploic veins include:

• Frontal Diploic Vein: Located in the frontal bone, it drains into the superior sagittal sinus.
• Anterior Temporal Diploic Vein: Found in the temporal bone, it drains into the sphenoparietal sinus.
• Posterior Temporal Diploic Vein: Also in the temporal bone, it drains into the transverse sinus.
• Occipital Diploic Vein: Located in the occipital bone, it drains into the occipital sinus.

Function

The primary function of the diploic veins is to facilitate the drainage of blood from the cranial bones. They play a crucial role in the regulation of intracranial pressure by providing a pathway for blood to exit the skull. Additionally, they help in the thermoregulation of the brain by allowing heat exchange between the blood and the cranial bones.

Clinical Significance

The diploic veins can be involved in various medical conditions. For instance, they may become engorged or thrombosed in cases of increased intracranial pressure or cranial trauma. Their proximity to the venous sinuses also makes them a potential route for the spread of infection from the cranial bones to the meninges.

Related Pages

• Cranial bones
• Venous sinuses
• Intracranial pressure
• Dura mater