keményagyhártya

The dura mater, known in Hungarian as keményagyhártya, is the outermost of the three meninges, the membranes that protect the brain and spinal cord. It is a thick, tough, and fibrous layer that forms the outermost covering of the central nervous system. The name "dura mater" is Latin for "tough mother," reflecting its protective role. In the cranial cavity, the dura mater is closely adhered to the skull. It is composed of two layers: an outer periosteal layer that is continuous with the periosteum of the skull bones, and an inner meningeal layer. These two layers are usually fused except in certain areas where they separate to form venous sinuses, such as the superior sagittal sinus. The dura mater plays a crucial role in supporting the brain and spinal cord, and its toughness provides significant protection against physical trauma. It also helps to compartmentalize the cranial cavity, preventing excessive movement of the brain within the skull. The dura mater extends downwards to enclose the spinal cord, forming the dural sac.