Applied Anatomy
Plentiful sebaceous glands make the scalp one of the most common sites for sebaceous cysts.
Wounds in the scalp bleed profusely because the fibrous fascia prevents vasoconstriction.
The emissary veins do not have valves and open in the loose areolar tissue; therefore, infection can be transmitted from the scalp to the cranial cavity. The layer of loose areolar tissue is known as the dangerous area of the scalp.
Metastatic spread of malignant lesions in front of the auricle is to the parotid and cervical groups of lymph nodes. The posterior part of the scalp is drained to the occipital and posterior auricular groups of lymph nodes.
Wounds superficial to the aponeurosis gap much less than wounds that cut through it because aponeurosis holds the skin tight.
During a difficult birth, bleeding may occur between the neonate’s pericranium and calvaria, usually over one parietal bone, because of a rupture of multiple minute periosteal arteries. The resulting collection of blood several hours after birth is known as cephalohematoma.
Anastomosis exists at the medial angle of the eye, between the facial branch of the external carotid artery and the cutaneous branch of the internal carotid artery. During old age, if the internal carotid artery undergoes atherosclerotic changes, the intracranial structures can receive blood from the connection of the facial artery to the dorsal nasal branch of the ophthalmic artery.
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