Superficial Face and Parotid Region Flashcards
What nerve fibers pass through the Infraorbital foramen?
Infraorbital n. (V2)
What formina lie directly superior and inferior to the infraorbital foramen and also carry fibers of the trigeminal nerve (CN V)?
- Associated Bones?
Supraorbital Foramen (frontal bone) - Supraorbital n. (V1)
Infraorbital Foramen (Maxillary bone) - Infraorbital n. (V2)
Mental Foramen (Mandible) - Mental n. (V3)
**All just take the name of the foramen
What is a common job of the supraorbital (V1), Infraorbital (V2) and Mental (V3) nerves?
- They all provide major cutaneous innervation to the face
What pharyngeal arch to the muscles of facial expression arise from?
2nd pharyngeal arch (so innervated by CN VII)
What is the general origin and insertion of the facial mm.?
Originate from bone
Insert onto skin
What parts of the orbicularis oris m. are involved in gently closing the eye and which are involved in tight closure?
- Palpebral (inner) portion gently closes the eyelids
- Orbital Part (outer ring) closes eyelids more tightly
(CN VII innervated)
What muscle would you flex to wink an eye?
- Palpebral AND Orbital part
What does the occipitofrontalis mm. do?
- Elevates eyebrows and wrinkles to forehead
CN VII innervated
What muscle forms the sphincter around the mouth?
Orbicularis Oris
What is the function of orbicularis oris?
- Protrudes Lips
- Puckers the Mouth
What is the common insertion of levator labii superioris and depressor labii inferioris?
- actions
BOTH insert into fibers of Orbicularis oris
Levator Labii Superioris action:
- Elevates upper lip and raises the angle of the mouth
Depressor Labii Inferioris action:
- Pulls lip inferiorly and laterally
What is the action of zygomaticus major and minor?
Pulls corner of the mouth superiorly and laterally
Where does zygomaticus major insert?
Into the skin at the corner of the mouth
What is the job of Levator and Depressor Anguli oris?
Levator Anguli Oris:
- Raises angle of the mouth
Depressor Anguli oris:
- pulls angle of the mouth inferiorly and laterally
What facial muscle orginates in part from the pterygomandibular raphe?
- Buccinator
What are the jobs of the buccinator?
- Presses Cheek against too during mastication to keep food out of oral vestibule
- Active when expelling air from oral cavity (blowing)
What does the investing fascia continue as superiorly in the parotid region?
- Parotid Fascia or Capsule
Describe the complete path of the parotid duct?
- where does it empty?
- Anterior Border of Parotid
- Extends forward below to zygomatic bone
- Crosses the Masseter
- Turns deep at anterior border of buccal fat pad
- Penetrates Buccinator m.
- Opens at 2nd molar
What is the isthmus of the parotid gland?
- What is anterior and posterior
- Waist-like constriction of Parotid
Anterior:
- Ramus of Mandible
- Masseter
Posterior:
- Mastoid process
What major nerve, artery, and vein course THROUGH the parotid?
Nerve:
Facial n. (CN VII)
Vein:
Retromandibular
Artery:
External Carotid
What fascial layers bound the Lateral Pharyngeal Space?
- Partoid Fascia (continuation of investing fascia)
- Buccopharyngeal Fascia
What space does the lateral pharyngeal space communicate with medially?
Retropharyngeal
What is the relationship between the vein artery and nerve that are buried in the parotid from superficial to deep?
Superficial: CN VII
Middle: Retromandibular v.
Deep: External Carotid a.
What is the trunk of CN VII?
- CN VII as it emerges from stylomastoid foramen before it divides into inferior (Cervicofacial) and superior (Temporofacial) divisions
What nerve provides GVE innervation to the parotid?
- associated ganglia
NOTE: GVE = Parasympathetic in head
Nerve:
Glossopharyngeal N. (IX)
Ganglia:
Otic Ganglia
What nerve provides GSA innervation to parotid capsule/ sheath?
- C2 and C3 via Great Auricular n.
2. Mandibular Division (V3) of trigeminal n.
Where does the mental nerve become its own branch of V3?
- course
- Branches from inferior alveolar n. as inf. alveolar n. descends into mandibular foramen
2. Continues on medial side of mandible
3. Goes through the mental foramen to the outside of the face
What innervates the tip of the nose to the occipital part of the head?
Opthalmic division (V1)
*Via Supraorbital n.
Note: this includes upper eyelids
What innervates (GSA) the lower eyelids to the top lip?
Maxillary Division (V2)
*Via Infraorbital n.
What innervates (GSA) to lower lip and chin to the top half of the ear?
Mandibular division of (V3)
*Via mental n.
T or F: besides the supraorbital, infraorbital, and mental nn. there are other nn. that are important to filling out dermatomes of the face
True
What does the auriculotemporal n. do?
- Innervates Skin around the ear and superior pt. of parotid capsule
Where do the following components of CN IX go?
- GVE
- BE
- GSA
- GVA
- SA
GVE - parasympathetic to partoid gland
BE - stylopharyngeus
GSA - Posterior tongue, palatine tonsils, oropharynx, mucosa of middle ear and auditory tube
GVA- Carotid body and Sinus
SA - taste to posterior 1/3 of tongue
What nerve provides parasympathetic innervation to the parotid gland?
- Ganglion used (for parasympathetics)?
Tympanic Nerve (CN IX)
Ganglion:
- Parotid Ganglia (postsynaptic bodies)
brain)
How does the tympanic n. (CN IX) get to the tympanic cavity?
- Passes through the Tympanic Canaliculus (between Jugular foramen and Carotid Canal)
Where do the GSA cell bodies of the Tympanic n. (CN IX) lie?
- Inferior and Superior Petrosal Ganglion (GSA)
- Pre-ganglionics for GVE lie in brainstem motor nuclei
Where is the inferior petrosal ganglion located?
OUTSIDE the skull, just outside the jugular foramen
Where does the Tympanic n. Recieve GSA signals?
- Internal Tympanic Membrane
- Auditory Tube
- Other pts. of middle ear mucosa
What does CN IX continue as it its preganglionic parasympathetic fibers travel beyond the middle ear plexus?
- Lesser Petrosal n.
Describe the Course of the lesser petrosal n.
- Passes forward THROUGH PETROUS part of temporal bone
- EMERGES through HIATUS of LESSER Petrosal n.
- Crosses floor of MIDDLE cranial cavity
- Passes THROUGH foramen Ovale
- TERMINATES in the Otic Ganglion
Where is the Otic Ganglion located?
Medial to Mandibular n. in Infratemporal Fossa just below Foramen Ovale
What nerve do the PARAsympathetic fibers exiting the Otic ganglia, bound for the parotid ride on?
- Ride on Auriculotemporal Branch of V3 (this branch of V3 provides GSA to parotid capsule)
When does the tympanic n. change its name to the Lesser Petrosal n.?
After crossing though Hiatus of Lesser Petrosal n.
How do sympathetic branches get to the parotid gland?
They ride on branches of the external carotid
What artery provides the main blood supply to the face?
Facial A.
What is the route of the facial a. after curving over the border of the mandible?
- Curves Over mandible ANTERIOR to the masseter
2. Travels past ANGLE of the MOUTH to the medial side of the eye
What muscles of facial expression overlies the Facial a. near the angle of the mouth?
- Zygomaticus Major (and minor)
What is the relationship of the hypoglossal n. to the occipital a.?
- Wraps around medially to laterally to course anteriorly to the tongue mm.
What branch arises from the external carotid a. immediately above the posterior belly of the digastric?
Posterior Auricular n.
What is the relationship of the Posterior Auricular n. to:
- External Aucoustic Meatus
- Mastoid Process
- Styloid Process
- Posterior the EAM
- ANTERIOR to Mastoid
- Posterior and Superior to Styloid Process
What muscle parallels the posterior auricular a.?
Stylohyoid
What Muscles and Structures are supplies by the Posterior Auricular a.?
- Parotid Gland
- Styloid mm. (stylohyoid, stylopharngeus, styloglossus)
- Posterior Digastric m.
What are the two terminal branches of the external carotid?
- Maxillary a.
2. Superficial Temporal a.
What bone does the maxillary a. run beneath?
mandible
Where does the Superficial Temporal a. begin?
Behind the neck of the Mandible, DEEP to the parotid gland
What branch of superficial temporal runs just lateral and inferior to the mandibular notch?
Transverse Facial a.
What major artery does the blood supply to the area just above the nose and eyebrows derive from?
- Internal Carotid a.
What artery allows for anastomoses of branches from the internal and external carotid aa?
Opthalmic Branch of internal Carotid
What vein runs parallel to the facial a. and where does it drain?
- Facial Vein
- Drains to Internal Jugular
What vein forms from tributaries on the scalp in the frontal and parietal region?
- Superficial Temporal Vein
The superficial temporal v. joins the ___________ to form the __________.
- Superficial Temporal + Maxillary v. = Retromandibular v.
What two veins join to form the external jugular v.?
- Retromandibular and Posterior Auricular vv.
Where is the frequently occurring communication between the facial v. and the external jugular usually seen?
Near or along the SCM
What major vein(s) lie(s) in the danger area and why is it called the danger area?
- Facial Vein and its branches
- Dangerous because infection can travel through the opthalmic vv. to the cavernous sinus or to the pterygoid plexus into the cavernous sinus
What structures are at risk when doing buccal fat pad cosmetic surgery?
- Parotid Duct
2. Buccal Branches of VII
What part of the parotid is typically involved in cancers?
Superficial Part
T or F: most cancers of the parotid gland are benign.
True, 80% are benign
When do malignant tumors of the parotid come to clinical attention?
- Whey they begin pressing on the facial n.
- Can invade the facial nn. themselves
What is the most common cause of nontraumatic facial paralysis?
- Inflammation of the Facial n. near its exit point at they Stylomastoid Foramen
- Produces Edema and nerve compression in the facial canal
What nerve is affected by Bell’s palsy?
- what causes it?
- Facial n.
- Cause is poorly understood (could follow exposure to cold temperature or virus)
Where does superficial temporal branch from the external carotid?
Posterior to the notch of the mandible
What are the anterior, posterior, and superior borders of the parotid bed?
Anterior:
- Half of the masseter
Posterior:
- External Auditory Meatus, and SCM
Superior:
- Zygomatic arch (temporal pt)
