The dural venous sinuses (also called dural sinuses, cerebral sinuses, or cranial sinuses) are venous

Vein

In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...

 channels found between layers of dura mater

Dura mater

The dura mater , or dura, is the outermost of the three layers of the meninges surrounding the brain and spinal cord. It is derived from Mesoderm. The other two meningeal layers are the pia mater and the arachnoid mater. The dura surrounds the brain and the spinal cord and is responsible for...

 in the brain

Brain

The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...

. They receive blood

Blood

Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

 from internal and external vein

Vein

In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...

s of the brain, receive cerebrospinal fluid

Cerebrospinal fluid

Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...

 (CSF) from the subarachnoid space

Subarachnoid space

In the central nervous system, the subarachnoid cavity is the interval between the arachnoid membrane and pia mater....

, and ultimately empty into the internal jugular vein

Internal jugular vein

The two internal jugular veins collect the blood from the brain, the superficial parts of the face, and the neck.-Path:On both sides and at the base of the brain, the inferior petrosal sinus and the sigmoid sinus join to form the internal jugular vein...

.

Venous sinuses

Name	Drains to
Inferior sagittal sinus Inferior sagittal sinus The inferior sagittal sinus , within the human head, is an area beneath the brain which allows blood to drain outwards posteriorly from the center of the head. It drains to the straight sinus , which connects to the transverse sinuses...	Straight sinus
Superior sagittal sinus Superior sagittal sinus The superior sagittal sinus , within the human head, is an unpaired area along the attached margin of falx cerebri. It allows blood to drain from the lateral aspects of anterior cerebral hemispheres to the confluence of sinuses...	Typically becomes right transverse sinus
Straight sinus Straight sinus The straight sinus , within the human head, is an unpaired area beneath the brain which allows blood to drain from the inferior center of the head outwards posteriorly...	Typically becomes left transverse sinus
Occipital sinus Occipital sinus The occipital sinus is the smallest of the cranial sinuses.It is situated in the attached margin of the falx cerebelli, and is generally single, but occasionally there are two....	Confluence of sinuses
Confluence of sinuses Confluence of sinuses The confluence of sinuses or torcular herophili is the connecting point of the superior sagittal sinus, straight sinus, and occipital sinus. It is found deep to the occipital protuberance of the skull. Blood arriving at this point then proceeds to drain into the left and right transverse sinuses...	Reference point, not an actual sinus
Sphenoparietal sinuses	Cavernous sinuses
Cavernous sinuses	Superior and inferior petrosal sinuses
Superior petrosal sinus Superior petrosal sinus The superior petrosal sinus is a venous structure located beneath the brain. It receives blood from the cavernous sinus and passes backward and laterally to drain into the transverse sinus....	Transverse sinuses
Transverse sinuses Transverse sinuses The transverse sinuses , within the human head, are two areas beneath the brain which allow blood to drain from the back of the head. They run laterally in a groove along the interior surface of the occipital bone...	Sigmoid sinus
Inferior petrosal sinus Inferior petrosal sinus The inferior petrosal sinuses, within the human head, are beneath the brain and allow blood to drain from the center of the head.They drain on either side inferiorly from the cavernous sinus and join with the sigmoid sinus to form the internal jugular vein, which continues inferiorly to drain...	Sigmoid sinus
Sigmoid sinuses	Internal jugular vein

Structure

The walls of the dural venous sinuses are composed of dura mater

Dura mater

The dura mater , or dura, is the outermost of the three layers of the meninges surrounding the brain and spinal cord. It is derived from Mesoderm. The other two meningeal layers are the pia mater and the arachnoid mater. The dura surrounds the brain and the spinal cord and is responsible for...

 lined with endothelium

Endothelium

The endothelium is the thin layer of cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. These cells are called endothelial cells. Endothelial cells line the entire circulatory system, from the heart...

, a specialized layer of flattened cells found in blood vessel

Blood vessel

The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...

s. They differ from other blood vessels in that they lack a full set of vessel layers (e.g. tunica media

Tunica media

The tunica media is the middle layer of an artery or vein.-Artery:It is made up of smooth muscle cells and elastic tissue...

) characteristic of arteries

Artery

Arteries are blood vessels that carry blood away from the heart. This blood is normally oxygenated, exceptions made for the pulmonary and umbilical arteries....

 and vein

Vein

In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...

s. It also lacks valves as seen in veins.

Clinical relevance

The sinuses can be injured by trauma. Damage to the dura mater

Dura mater

The dura mater , or dura, is the outermost of the three layers of the meninges surrounding the brain and spinal cord. It is derived from Mesoderm. The other two meningeal layers are the pia mater and the arachnoid mater. The dura surrounds the brain and the spinal cord and is responsible for...

, which may be caused by skull fracture, may result in blood clot

Thrombosis

Thrombosis is the formation of a blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel is injured, the body uses platelets and fibrin to form a blood clot to prevent blood loss...

 formation (thrombosis) within the dural sinuses. While rare, dural sinus thrombosis may lead to hemorrhagic infarction

Infarction

In medicine, infarction refers to tissue death that is caused by a local lack of oxygen due to obstruction of the tissue's blood supply. The resulting lesion is referred to as an infarct.-Causes:...

 with serious consequences including epilepsy

Epilepsy

Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...

, neurological deficits, or death.