Acute subdural hematoma is usually caused by external trauma that creates tension in the wall of a bridging vein as it passes between the arachnoid and dural layers of the brain’s lining—i.e., the subdural space. The circumferential arrangement of collagen surrounding the vein makes it susceptible to such tearing.

What causes tearing of the bridging veins?

Acute subdural hematoma is usually caused by external trauma that creates tension in the wall of a bridging vein as it passes between the arachnoid and dural layers of the brain’s lining—i.e., the subdural space. The circumferential arrangement of collagen surrounding the vein makes it susceptible to such tearing.

What bleed is caused by damage the bridging veins?

An ASDH commonly results from tearing of one or more bridging veins. This lesion also occurs from hemorrhagic contusions or intracerebral hematomas and from injury to a cortical artery or vein. Nontraumatic ASDHs can originate from a ruptured arteriovenous malformation or intracranial aneurysm.

What is the most common cause of subdural hemorrhage?

The most common cause for a subdural hematoma is head injury. This can be from a car crash, fall, or violent attack. This sudden impact can strain the blood vessels within the dura, causing them to rip and bleed. Sometimes small arteries also break within the subdural space.

What is the function of bridging veins?

Bridging veins drain the venous blood from the cerebral cortex into the superior sagittal sinus (SSS) and doing so they bridge the subdural space. Despite their importance in head impact biomechanics, little is known about their properties with respect to histology, morphology and mechanical behaviour.

What are bridging veins?

Bridging veins are veins in the subarachnoid space that puncture the dura mater and empty into the dural venous sinuses. A rupture of a bridging vein causes a subdural hematoma.

Where are bridging veins?

Can you have a bleed on the brain and not know?

There may be no warning signs of a bleed on the brain. For example, it could happen after someone falls and hits their head. If there is a weakness in the blood vessel wall, it can bulge or swell, which is known as an aneurysm. Aneurysms can rupture suddenly without warning, and cause a bleed on the brain.

Are bridging veins emissary veins?

The bridging veins (BVs) derive from the embryonic pial-arachnoidal veins and connect the pial veins with the dural sinuses or plexuses. The emissary veins (EVs) on the other hand represent the remaining connections of the superficial venous system with the dural venous system during the development of the skull.