What is the Sagittal Sinus?

The sagittal sinus is a large vein found in the human head. This vein travels over the top portion of the skull, beginning at the top of the skull and moving to the back part of the skull. At this point, the vein splits into two sections and works to carry blood back to the heart from the vein. The two sections of this vein are known as the superior sagittal sinus and the inferior sagittal sinus.

The superior sagittal sinus is sometimes referred to as the superior longitudinal sinus. This sinus is located above and behind the human brain, but inside of the skull bone known as the cranium. This placement allows veins to move from across the top of the head to the back of the head. It is widely believed that the spinal liquid known as cerebrospinal fluid is drained into the superior sagittal sinus from the arachnoid granulations, small valves responsible for transporting cerebrospinal fluid.

The inferior sagittal sinus, also called the inferior longitudinal sinus, is found underneath the brain. The inferior sagittal sinus allows blood vessels to span the area of the head from the center to the back of the head. This sinus travels from the falx cerebri to the corpus callosum. The falx cerebri is a sickle-shaped structure that has a tendency to calcify with age. The corpus callosum helps to give the human brain the ability to coordinate sensory as well as motor impulses.

Cerebral venous sinus thrombosis, often simply referred to as CVST, is a medical condition affecting both the superior and inferior sagittal sinuses. CVST is a type of stroke that occurs due to a blood clot in the sinuses. Symptoms of this condition can include headache, vision changes, muscle weakness affecting the face and libs on the affected part of the body, and, in some cases, seizures. Treatment generally begins with medications prescribed to keep the blood from clotting. In some cases, surgical intervention to remove the clots and promote drainage of fluids from the brain may be required.

Traumatic brain injuries can also lead to damage involving the sagittal sinus. Surgery is often required when this type of injury exists. The prognosis in this situation depends on the extent of the damage. If the flow of blood is compromised for a prolonged period of time, normal brain function may not be able to be restored.