Numerous arteries nourish the hair follicles and dermis layer of the scalp. The University of Michigan Medical School notes that the dense connective tissue of the scalp holds these arteries firmly in place; this causes the arteries to remain open instead of restricting when cut or injured and causing excessive bleeding from the head. The blood supply of the scalp largely stems from branches of arteries that travel through the neck, brain and head.
Frontal Arteries
The front and top of the scalp are largely supplied by the frontal, supraorbital, supratrochlear and lachrymal arteries. These arteries arise from the internal carotid artery, a large primary artery that runs from the neck into the brain, where it branches into various areas. Some of these arteries possess corresponding nerves that have similar names and follow similar paths in the scalp.
Lateral Arteries
The lateral, or side, arteries of the scalp are the superficial temporal artery and the posterior auricular artery. These branches stem from the external carotid artery, a primary artery that supplies the face with blood, as described by the University of Michigan Medical School. As their names suggest, the superficial temporal artery runs close to the surface of the scalp in the side, or temporal, lobe, and the superficial artery is a shallow artery that runs behind the ear along the side and top of the scalp. The temporal artery consists of both anterior and posterior branches.
Posterior Arteries
The occipital artery is the main artery that infuses the scalp at the back of the head with blood. It runs parallel to the greater occipital nerve that innervates this area. As its name suggests, this artery runs up and over the occipital lobe of the brain. The occipital artery extends from the external carotid artery that supplies the neck and parts of the brain and brain stem with blood, according to the StrokeCenter.org.
