Periosteal Cranial Dura Mater

Structure

The periosteal cranial dura mater is the superficial layer of cranial dura. It is superficial to the meningeal dura and deep to the inner compact layer of bone making up the cranium. The internal surface of the cranium does not exhibit a periosteum, instead the outer layer of dura acts as this periosteum, hence the name.

The periosteal dura is firmly adhered to the meningeal dura in most places, except when they come apart at the dural venous sinuses. This thick fibrous material blends with the bone at the foramina on the basal surface of the skull and is firmly adhered to the sutures between bones.

A number of small vessels exist within the dura, the meningeal vessels. If these vessels rupture due to trauma, blood will accumulate in the space between the periosteal dura and the calvaria, the epidural space. The accumulation of blood during epidural hemorrhage is limited to the spaces between the sutures, as the periosteal dura is firmly adhered to the bone here, thus on CT and MRI it presents as a convex lesion.

Key Features/Anatomical Relations

The periosteal cranial dura mater is adherent to the inner surface of the cranial bones, especially along the sutures and foramina. It is continuous with the pericranium, covering the outer surfaces of the cranial bones, through the cranial sutures and the foramina. Additionally, it is continuous with the periosteum of the orbit via the superior orbital fissure.

List of Clinical Correlates

—Epidural hematoma

—Headache