Scalp and Superficial Face Flashcards
1
Q
What are the 5 layers of the scalp?
A
*use SCALP mnemonic*
- Skin (integument)
- Connective tissue (dense CT)
- Aponeurosis
- Loose areolar CT
- Pericranium (periosteum)
2
Q
What is the cutaneous innervation of the face and scalp?
A
-
trigeminal N. (CN V): front part of the face and anterosuperior part of the scalp
- opthalmic (V1) division: supraorbital N., supratrochlear N., and infratrochlear N.
- maxillary (V2) division: infraorbital N., zygomaticofacial N., zygomaticotemporal N.
- mandibular (V3) division: mental N., buccal N., auriculotemporal N.
-
spinal nerves C2-3
- anterior rami of C2, C3: greater auricular and lesser occipital Ns.
- posterior rami of C2: greater occipital N.
3
Q
What is the sensory component of the trigeminal N.?
What pathways does its branches take?
A
- ophthalmic (V1) division: exits cranium via superior ophthalmic (orbital) fissure (supraorbital N. exits via supraorbital foramen, supratrochlear N. exits via supratrochlear foramen, and infratrochlear N.)
- maxillary (V2) division: exits cranium via foramen rotundum (infraorbital N. exits infraorbital foramen)
- mandibular (V3) division: exits cranium via foramen ovale (mental N. exits via mental foramen, buccal N.)
4
Q
What is the arterial supply of the scalp?
A
- posterior auricular A. (from external carotid)
- superficial temporal A. (from maxillary)
- occipital A. (from external carotid)
- supraorbital/supratrochlear A. (ophthalmic A.)
5
Q
- superficial injury: superficial to aponeurosis, holds edges of wounds together
- deep injury: through aponeurosis, forms gap because of pull of occipitofrontalis M.
- both bleed profusely as CT tends to hold cut vessels open
- infections: can spread into cranium via small emissary veins (anastomoses between intra- and extracranial veins)
A
scalp injuries
6
Q
What are the muscles of facial expression?
A
- epicranius M. (frontalis and occipitalis): create expressions of surprise and/or fright; also collectively called occipitofrontalis M.
- orbicularis oculi M.: orbital and palebral portions; close eyelids
- levator labii superioris M.: lifts upper lip
- zygomaticus major and minor and levator anguli oris M.: smiling and laughing muscles
- depressor labii inferioris M. and depressor anguli oris M.: depress lower lip
- orbicularis oris M.: closes mouth and pout
- buccinator M.: muscle of cheek, holds cheek close to teeth
- buccinator and oribicularis oris M.: kissing muscles
*all innervated by facial N. (CN VII)*
7
Q
Describe facial N. (CN VII):
- motor innervation:
- sensory innervation:
- autonomic innervation:
A
- motor innervation: facial expression muscles (posterior auricular, temporal region, zygomatic region, buccal region, mandibular region, and cervical region)
- sensory innervation: taste anterior 2/3 of tongue
- autonomic innervation: parasympathetics to lacrimal, nasal cavity, and submandibular and sublingual glands
8
Q
- damage of facial N. due to surgery or infection
- muscle weakness/paralysis including inability to close eyelides (prone to cornea ulceration)
A
Bell’s palsy
9
Q
- tx that blocks neuromuscular transmission by inhibiting acetylcholine release
- used to treat eye disorders, migraines, muscle spasms, and used cosmetically
A
botox injections
10
Q
What is the OIN of the muscles of mastication?
A
- masseter M.: origin at zygomatic arch, insertion at lateral ramus and angle of mandible
- temporalis M.: origin at floor of temporal fossa and deep temporal fascia, insertion at coronoid process and anterior border of mandible; elevates and closes mandible, contributes to mandibular retraction
- medial pterygoid M.: origin at medial surface of lateral pterygoid plate and maxillary tuberosity, insertion at medial surface of mandibular ramus; elevates and protrudes mandible
- lateral pterygoid M.: origin at greater wing of sphenoid and lateral surface of lateral pterygoid plate, insertion at neck of mandible, articular disc, and TMJ capsule; protracts mandible, swings jaw to contralateral side, contributes to lateral chewing
*all innervated by trigeminal N., mandibular division (CN V3)*
11
Q
What muscles does the trigeminal N. provide motor innervation to?
A
- muscles of mastication: masseter, medial pterygoid, lateral pterygoid, temporalis
- mylohyoid M.
- anterior giastric M.
- tensor tympani M.
- levator veli palatini M.
12
Q
- initial infection of chickenpox virus
- lesions due to reactivation of virus that can appear anywhere on the body
- many produce lesions in cranial ganglia w/ most involving trigeminal N. (CN V)
- ophthalmic division commonly affected, usual cornea involved leading to painful corneal ulceration
A
herpes zoster virus
13
Q
What are the 3 salivary glands?
A
- parotid gland: largest, serous gland encapsulated by tough fascia
- submandibular gland: located in submandibular triangle inferior to mandible, mixed serous and mucous gland
- sublingual gland: located within oral cavity beneath tongue, mucous gland
14
Q
What are the structures found within/near the parotid gland?
A
- parotid duct: runs over masseter M., pierces buccinator and opens on surface of oral cavity near upper second molar
- facial N.: exits stylomastoid foramen and enters the gland after innervating stylohyoid and posterior digastric M.
- retromandibular V.
- external carotid A.
- auriculotemporal N.: CN V3 sensory
15
Q
Describe the vascularization of the face and scalp:
A
- facial A.: branch off external carotid A.; gives rise to labial and angular As.
- occipital A.: branch off external carotid A.; supplies posterior scalp
- posterior auricular A.: branch off external carotid A.
- superifical temporal A.: terminal branch of external carotid A.
- transverse facial A.: branch off the superficial temporal A.
- infraorbital A.: branch off the maxillary A.
- supraorbital and supratrochlear As.: branches off ophthalmic A.
- mental A.: terminal branch of inferior alveolar A.
28
Q
Describe the vein distribution of the face and scalp:
A
- generally follow path of the As.
- facial V. empties into internal jugular but has other anastomoses
- superficial temporal Vs.: join maxillary V. to form retromandibular V.
- retromandibular V.: joins posterior auricular V. to make external jugular
- anastomoses between supratrochlear, supraorbital, angular V. of facial V. w/ intracranial Vs. (potential spread of exterior infections into the cranium)
29
Q
Describe the lymphatics of the face and scalp:
A
- superficial cervical nodes: located along EJV draining superficial tissues of neck (submental, submandibular, parotid, mastoid, and occipital nodes)
- inferior deep cervical nodes: drain lateral cervical area and run along path of SCM (jugulo-digastric and jugulo-omohyoid nodes)
- all drain into nodes and lymphatics running along IJV
- lymphatics join to form lymphatic trunks that then join to form lymphatic ducts that empty into subclavian vein near its junction w/ IJV
