Cerebrovasculature

Cerebrovasculature refers to the network of blood vessels that supply blood to the brain. This intricate system is crucial for delivering oxygen and nutrients essential for neuronal function and for removing metabolic waste products. The cerebrovasculature includes arteries, veins, capillaries, and venules, all working together to maintain brain health.

The primary arteries supplying the brain are the internal carotid arteries and the vertebral arteries. These large vessels branch into smaller arteries, eventually forming the arterial circle of Willis, an anastomotic ring that provides a critical redundancy in blood supply to the brain. From these arteries, smaller arterioles and then capillaries penetrate the brain tissue. Capillaries are the smallest blood vessels and are where the exchange of oxygen, nutrients, and waste products occurs between the blood and the brain cells.

Deoxygenated blood and waste products are collected by venules, which merge into larger veins. The major venous drainage pathways include the superficial and deep cerebral veins, which eventually drain into the dural venous sinuses. These sinuses are large venous channels located between the layers of the dura mater, the outermost membrane covering the brain. Ultimately, the blood from the dural venous sinuses empties into the internal jugular veins, returning to the heart.

The cerebrovasculature is protected by the blood-brain barrier, a highly selective semipermeable border that separates the circulating blood from the brain extracellular fluid, preventing the passage of most pathogens and large molecules. Diseases affecting the cerebrovasculature, such as stroke, aneurysms, and arteriovenous malformations, can have severe consequences due to the brain's limited capacity for self-repair.