7. Superficial Face and Scalp Flashcards
5 layers of the scalp
- skin
- connective tissue (dense)
- aponeurosis
- loose connective tissue
- pericranium
contains abundant arterial supply & glands
skin
thick, dense richly vascularized subcutaneous layer & nerves
connective tissue
broad, strong tendinous sheet; attachment for muscles
aponeurosis
sponge-like layer, potential space
loose connective tissue
dense layer of connective tissue that forms the external periosteum of the neurocranium
pericranium
Why can partially detached scalps be replaced with good chance of healing?
- nerves and vessels of the scalp enter inferiorly and ascend through layer 2 to the skin
- *scalp arteries are well-protected by dense connective tissue & anastamose freely
What is the “danger layer of the scalp”? Why is it called that?
loose connective tissue layer: pus or blood spreads easily in it
[infection can spread to the cranial cavity because it can pass through small emissary veins and reach the meninges]
When is a scalp wound considered a “gaping wound”?
if the wound cuts through the aponeurosis
superficial structures of the face
- parotid gland and duct
- cutaneous nerves: great auricular n.
- facial n. & branches
- muscles of facial expression
- muscles of mastication
- facial a. and v.
muscles of the scalp and face
Name muscles responsible for these expressions.
Name muscles responsible for these expressions.
Name muscles responsible for these expressions.
muscles of mastication
- temporalis m.
- masseter m.
- lateral pterygoid m.
- medial pterygoid m.
parotid plexus (branches of the facial n.)
- temporal branch
- zygomatic branch
- buccal branch
- marginal mandibular branch
- cervical branch
[mnemonic: A tiny zebra bit my cheek.]
- crosses zygomatic arch
- supplies:
- auricularis superior m. and auricularis anterior m.
- frontal belly of occipitofronalis m.
- superior part of the orbicularis oculi m.
temporal branch of CN VII
- passes via 2 or 3 branches superior and mainly inferior to eye
- supplies: inferior part of orbicularis oculi m. & other facial muscles inferior to orbit
zygomatic branch of CN VII
- passes external to the buccinator m.
- supplies: buccinator m. and muscles of the upper lip (upper part of orbicularis oris m. and inferior fibers of levator labii superioris m).
buccal branch of CN VII
- emerges from the inferior border of the parotid gland and crosses the inferior border of the mandible deep to the platysma to reach the face
- supplies the risorius m. and muscles of the lower lip and chin
marginal mandibular branch of CN VII
- passes inferiorly from inferior border of the parotid gland and runs posterior to the mandible
- supplies platysma m.
cervical branch of CN VII
Trace sensory and motor nerves of the Facial N.
Sensory and motor nerves of CN VII enter the skull via internal acoustic meatus, then reach the geniculate ganglion. From the geniculate ganglion, arises the greater pterosaurs n., which then passes through Pterygoid canal & joins the deep petrosal n. (Sympathetic) to form the nerve to Pterygoid canal (Vidian n.) This joins zygomatic n and lacrimal n to innervates the lacrimal gland.
From the geniculate ganglion, other branches arise: (1) auricular branch of vagus n. (Conveying general sensory fibers of CN VII). Facial nerve then passes through the stylomastoid foramen and gives off branches: (1) superior posterior occipital is, (2) general sensory fibers of N. VII, (3) muscles of facial expression, (4) platysma/stylohyoid/digastric (posterior belly.) Chorda tympani innervates taste fibers plus general sensory fibers of N. VII including the submandibular and sublingual glands.
cutaneous innervation of the head/neck:
maxillary division of trigeminal nerve (V2)
- zygomatic nerve
- zygmaticofacial and zygomaticotemporal n.
- infraorbital nerve (infraorbital foramen)
- palatine branches
- branches to mucosa of maxillary sinus
- branhes to posterior teeth
cutaneous innervation of the head/neck:
mandibular division of trigeminal nerve (V3)
- mental nerve
- buccal nerve
- auriculotemporal nerve
cutaneous innervation of the head/neck:
medial branches of dorsal rami of cervical spinal nerves
- greater occipital n. (C2)
- 3rd occipital n.
- from 4th, 5th, 6th, and 7th nerves in sucession
cutaneous innervation of the head/neck:
branches from cervical plexus
- lesser occipital nerves (C2-C3)
- great auricular nerve (C2-C3)
- inferior aspect of auricular (external ear) and parotid region of face (angle of jaw)
- transverse cervical nerve ( C2-C3)
- supraclavicular nerve (C3-C4)
motor innervation of the muscles of mastication
V3: mandibular division of the trigeminal nerve
- branches of the facial artery
- origin/course/distribution
occipital artery origin/course/distribution
posterior auricular artery origin/course/distribution
superficial temporal artery origin/course/distribution
transverse facial artery origin/course/distribution
mental artery origin/course/distribution
supra-orbital & supratrochlear artery origin/course/distribution
veins of face and scalp
facial artery anastamoses
