8. Superficial Scalp and Face Flashcards
What are the layers of the scalp?
S-C-A-L-P
- Skin
- Connective tissue (dense)
- Aponeurosis
- Loose CT
- Pericranium
What layers make up the scalp proper?
1. Skin
2. CT (dense)
3. Aponeurosis
These layers are intimately connected and move together as a unit.
Describe the SCALP
- Skin: abundant BV and glands
- (dense) CT has alot of neurovasculature.
- Aponeurosis serves as the attachement site for muscle bellies converging from the forehead & occiput (occipitofrontalis muscle) & from the temporal bones on each side (temporoparietalis and superior auricular muscles). Structure are. called epicranius and I by the facial N.
- Loose CT has potential spaces that. can fill with fluid if there is injury or infection.
- Pericranium- forms the external periosteum of the neurocranium
CN: Detached Scalp:
Easy or hard to put on?
Detached scalp is v. easy. to put back on because all neurovascularture supply comes from inferior to superior. Thus, you can reconnect them during surgey.
CN: Scalp infection
- Loose CT (layer four) is danger area because pus or blood spreads easily.
- Can also pass into the cranial cavity through small emissary veins (pass through parietal foramina in calvaria) to reach intracranial structures –
- Within the eyelids, even a relatively slight injury or inflammation may result in an accumulation of fluid, causing the eyelids to swell
Gaping vs. Non-gaping wounds
- Gaping wounds: caused when you go through the APO
- Non-gaping wounds: wounds within skin of dense CT (first two layers)
Describe the parotid gland and duct and their relations to nerves, vessels and muscles and its innervation.
type of gland?
Location?
Parotid gland is the largest salivary gland: located lateral on the face, anterior and inferior to ear. Extends from temporal bone -> mandible anterior of the ear. It is covered in fascia.
Describe the parotid gland and duct and their relations to nerves, vessels and muscles and its innervation.
Sensory innervation:
Parasympathetic innervation:
- Sensory innervation: Great auricular N. and auriculotemporal N
- Parasympathetic innervation: Glossopharyngeal n. (CN IX) via posterior auricular n. (postsynaptic from otic ganglion).
Describe the parotid gland and duct and their relations to nerves, vessels and muscles.
Parotid duct relation?
Parotic gland relations?
- Parotid duct relation: dives in buccinator M.
-
Parotic gland relations:
- 1. CN 7 does not innervste it, but passes through it
- 2. Retromandibular vein
- 3. External carotid A.
Muscles of facial expression develop from __________.
2nd pharyngeal arch
Muscles of facial expression are innervated by:
- Motor innervation: CN VII (facial)
- Sensory innervation of the face and anteriorsuperior part scalp: mainly CN V (trigeminal N)
List the muscles of facial expression
Occipitofrontalis M
Axn:
Frontal belly of occipitofrontalis m: lift up eyebrows and wrinkles forehead
Occipital bellow of occipitofrontalis m: retract scalp, increasing effectivness of frontal belly
Orbicularis oculi m.
Axn:
Has two parts:
1. Orbital part of the Orbicularis oculi m: close eyelids tightly
- Palpebral part of the Orbicularis oculi: close eyelids gently.
Depressor labii inferioris m.
Axn:
Depresses lip inferiorly and
Orbicularis oris M.
Axn
- Sphincter around mouth
- Axn: Keeps mouth close; compresses and protrudes lips when kissing/blowing.
Zyogmaticus Major M
Axn:
Elevate labial commissure bilaterally to smile
Buccinator M.
Axn:
Cheek muscle.
- Presses cheek against molar teeth; works with tongue to keep food between occlusal surfaces and out of oral vestibule; resists distension (when blowing)
Levator anguli oris
Axn:
Dilates mouth; widens oral fissure when grinning or grimacing
Risorius M
Axn:
Pulls the angle of the mouth laterally.
Contractions of the risorius muscle produce: facial expression of pleasure and laughter.
Dilators of mouth
- Risorius m
- Levator labii superioris m
- depressor labii inferioris m
What m protrudes and elevates lower lip?
Mentalis
Corrugator supercilii M.
Axn
Draws eyebraws medially and inferiorly, creating wrinkles above nose
WORRY
What are your muscles of mastication
- Lateral ptyerygoid m.
- Medial pterygoid m.
- Masseter m.
- Temporalis m.
What innervates muscles of mastication?
Trigeminal Nerve (CN V3)
Trigeminal nerve is also the sensory nerve for the face.
What pharyngeal arch do muscles of mastication come from?
1st pharyngeal arch
What other muscles are innervated by trigeminal N?
1. Myelohyoid M (V3)
2. Anterior belly of digastric M (V3)
3. Tensor tympani m and tensor veli palantini m. (V3)
Facial nerve is associated with the derivatives of the _____ pharyngeal arch.
2nd
Actions of facial nerve (CN VII)
Has a motor root and sensory root
-
Motor: Innervates the muscles of facial expression via
- Temporal branch
- Zygomatic branch
- Buccal branch
- Mandibular branch
- Cervical branch
- Motor to [posterior belly. of digastric m. and stylohyoid m.]
- Sensory:
- Taste for the anterior 2/3 of tongue via chorda tympani
- Sends parasympathetic fibers to [lacrimal gland, submandibular and sublingual salivary glands]
- General sensory around concha of ear
Mneumonic for facial nerve branches.
pA TINY ZEBRA BIT MY COCK
- 1. Posterior auricular
- 1. Temporal branch
- 2. Zygomatic branch
- 3. Buccal branch
- 4. Mandibular branch
- 5. Cervical branch
Parasympathetic fibers to lacrimal gland travel with?
Parasympathetic fibers to submandibular and sublingual gland travel with?
1. Greater petrousal N.
2. Chordi tympani
Bell’s Palsy
• Unilateral facial nerve paralysis
Cannot blink, pucker lips, keep food in mouth while chewing (drooling
What are the actions of trigeminal nerve (CN 5)?
Motor and sensory root:
- 1. Motor: for muscles of mastication via V3 (mandibular nerve)
- 2. Sensory: sensory to to the face
Branches of Trigeminal N (CN V)
- Opthalamic nerve (CN V1); branches into
- Supratrochlear N: sensation to cornea -> upper eyelid-> forehead -> vertex of scalp
- Supraorbital N: sensation to foreheard-> scalp -> vertex of scalp
- External nasal branch of anterior ethmoidal N: bridge and tip of nose
- Maxillary nerve (CN V2) -> cheek, upper lip, side of nose, lower eye lid, temporal area
- Infraoribital N
- zygomaticifacial n.
- zygomaticotmeporal n
- Mandibular (CN V3); sensory and motor
- Mental N. -> chin
- Buccal N. -> sensory
- Auriculotemporal
What innervates Dura?
CN V (trigeminal)
What is herpes Zoster?
Shingle; chicken pox
In ppl who had CP without vaccination, virus is dormant in sensory ganglia.
Herpes zoster can follow trigeminal N dermatomes almost precisely (esp V1)
Trigeminal Neuralgia aka tic douloureux
Sensory disorder of CN V;
Sudden attacks of pain often due to compresion of V2 and V3.
Describe the course and major branches of the blood supply to the superficial face. Evaluate anastomoses of the face and determine supply and distribution.
Major BV:
Off of external carotid A.
- Facial A. and V.
* Give of- inferior labial A.
- Superior labial A.
- Angular A.
- Facial A. and V.
- Superficial temporal A.
- Transverse facial A and V (located in front of ear)
- Infraorbital A (branch of maxillary A).
Off of internal carotid A.
- Supraorbital A and V
- Supratrochlear A and V.
Why is plastic surgery. so easy. on. face?
FACE/SCALP LOVES ANASTOMSING! Brain and tongue do not.
- Lipsd: Facial A. branches into superior and inferior labial A.
- Supraorbital from ICA and superficial temporal A from ECA anastomose
- Eyes: Angular A from ECA anastomose with supraorbital A from ICA.
Face drains via:
external jugular vein
Are there LN in scalp?
No lymph nodes in the scalp, &
only located in the parotid/buccal region of the face
Lymphatic drainage of the face is made up of what two groups of LN?
- Superficial ring (pericervical collar) LN
- Deep cervical LN
Lymph drains into the superficial ring (pericervical collar) of lymph nodes located where?
1. Submental
2. Submandibular
3. Parotid
4. Mastoid
5. Occipital
Superficial ring of LN drain into where?
Deep cervical LN:
- Jugulo-digastric (upper deep cervicals)
- Jugulo-omohyoid (lower deep cervicals)
• Lymph from the lateral part of face, scalp, & eyelids → ___________
→ superficial parotid lymph nodes
• Lymph from the upper lip & lateral lower lip → ___________
submandibular lymph nodes
• Lymph from the chin & central lower lip →_________
submental lymph nodes
• Lymph from the sides and posterior to ear →_________
mastoid LN
• Lymph from the back of head and neck →_________
occipital LN
