Head and neck anatomy may be important in the development of the BBB. Astrocytes may also be responsible for transporting ions (electrolytes) from the brain to the blood. Blood from the brain and neck flows from: (1) within the cranium via the internal jugular veins, a continuation of the sigmoid sinuses. The right and left external jugular veins drain from the parotid glands, facial muscles, scalp into the subclavian veins. The right and left vertebral veins drain the vertebrae and muscles into the right subclavian vein and into the superior vena cava, into the right atrium of the heart. The lymphatic system drains the
Lesional demyelinations of the central nervous system ventricles within the brain. This morphologic appearance was named Dawson's fingers by Charles Lumsden, after the Scottish pathologist James Walker Dawson, who first defined the condition in 1916. "Dawson's fingers" is the name for the lesions around the ventricle-based brain veins of patients with multiple sclerosis. The condition is thought to be the result of inflammation or mechanical damage by blood pressure around long axis of medular veins. Dawson's fingers spread along, and from, large periventricular collecting veins, and are attributed to perivenular inflammation. Lesions far away from these veins are known as Steiner's splashes. Sometimes experimental autoimmune encephalomyelitis has