The Scalp Flashcards
what does the scalp refer to?
layers of skin and subcutaneous tissue that cover the bones of cranial vault
what are the layers of the scalp?
Skin dense Ct epicranial Aponeurosis Loose areolar ct Periosteum
which layers are tightly bound together?
first 3 - move together as a unit
skin, dense Ct, epicranial Aponeurosis
what does the skin contain?
numerous hair follicles and sebaceous glands - site for sebaceous cysts
what does the dense Ct do?
connects the skin to the epicranial aponeurosis
richly vascularised and inervated
why can the scalp be a site of profuse bleeding?
the blood vessels within the dense Ct are high adherent to the Ct
this renders them unable to fully constrict if lacerated
what is the epicranial aponeurosis?
a thin, tendon-like structure that connects the occipitalis and frontalis muscle
describe the loose areolar ct
a thin ct layer that separates the periosteum of the skull form the epicranial aponeurosis
what does the loose areolar ct consist of?
numerous blood vessels - including emissary veins which connect the veins of the scalp to the diploic veins and intracranial venous sinuses
describe the periosteum
outer layer of skull bones
what does the periosteum become continuous with? where?
becomes continuous with the endosteum at the suture lines
Clinical: scalp infections, where is the danger area of the scalp?
loose CT
clinical: why is the loose CT the danger area of the scalp?
because pus and blood spreads easily within it, and can pass into the cranial cavity along the EMISSARY veins
therefore, infection can spread from scalp to meninges - can lead to meningitis
where does the scalp receives its rich blood supply via?
external carotid artery and opthalmic artery
what is the opthalmic artery a branch of?
internal carotid
how many branches of the external carotid artery are involved? what are they?
3
superficial temporal
posterior auricular
occipital
what is the mnemonic for remember the branches of the external carotid artery?
some anatomists like freaking out poor medical students
what are the all the branches of the external carotid artery?
S: superior thyroid artery A: ascending pharyngeal artery L: lingual artery F: facial artery O: occipital artery P: posterior auricular artery M: maxillary artery S: superficial temporal artery
what does the superficial temporal artery supply?
frontal and temporal regions
what does the posterior auricular artery supply?
area superiorly and posteriorly to the auricle
what does the occipital artery supply?
back of the scalp
anterior and superiorly, where else does the scalp receive blood supply from?
2 branches of the opthalmic artery:
supraorbital artery
supratrochlear artery
how is the venous drainage of the scalp divided?
into superficial and deep components
what does the superficial venous drainage follow?
the arteries: (SOP,SS) superficial temporal occipital posterior auricular supraorbital supratrochlear
