Face and Parotid Flashcards
Describe the three types of Le Fort fractures.
Type 1: horizontal maxillary fracture separates the upper teeth from the upper face.
Type 2: pyramidal fracture separates the upper teeth + the nasal bones from the upper face.
Type 3: horizontal fracture through the orbits, superior to the nasal bones - craniofacial disjunction.
What is the philtrum? What is the glabella?
The philtrum is the indent thingy in the middle of the upper lip.
The glabella is the space between the eyebrows.
Describe the fascial layers of the face.
There is a superficial fascia with a lot of fat but NO DEEP FASCIA except for in the regions of the parotid glands, masseter, and temporalis muscles. The deep fascia around these are extensions of the investing fascia around the neck.
Loss of elastin and collagen fibers in the skin results in ______.
wrinkles
Botox blocks the release of __________ at the neuromuscular junction.
acetylcholine
A 13-year-old girl visits her pediatrician complaining of loss of sensitivity in her lower eyelid, the skin below her right eye, and in her upper lip and teeth.
Which of the following sites is the most likely location for the nerve lesion responsible for these signs and symptoms?
a) Foramen spinosum
b) Foramen ovale
c) Foramen rotundum
d) Superior orbital fissure
e) Petrotympanic fissure
Which nerve(s) has been affected in this case?
c) Foramen rotundum
V2
CN V originates from the _____.
pons
Which branch(es) of the trigeminal nerve carry sensory fibers? Where do these cell bodies live?
All three branches have sensory fibers. Cell bodies live in the trigeminal ganglion.
Where in the skull is the trigeminal ganglion located?
Middle cranial fossa
Which branch(es) of the trigeminal nerve have motor fibers?
V3 only - for 8 muscles of mastication.
Name the foramen that each branch of the trigeminal nerve exits the skull.
V1 goes through the superior orbital fissure.
V2 goes through the foramen rotundum.
V3 goes through the foramen ovale.
Which nerve supplies general sensation to the inside of the cheeks?
Long buccal (V3)
Trigeminal neuralgia is likely caused by enlargement of which blood vessel?
The superior cerebellar artery
What types of fibers does the facial nerve (CN VII) contain?
- Somatic motor for muscles of facial expression and scalp.
- Somatic sensory to the tragus of the ear.
- Visceral motor (glands - parasympathetic) to the lacrimal and mucosal glands of the nasal cavity and soft palate via the greater petrosal and the submandibular and sublingual glands via the chorda tympani.
- Special sensory - taste from the anterior 2/3 of the tongue via the chorda tympani.
Nerves from CN VII pierce the _______ gland after exiting the ________ foramen.
parotid after exiting the stylomastoid foramen.
The buccinator muscle is supplied by the ______ branch of CN VII, while the cutaneous sensation of the skin covering the buccinator is provided by CN ____.
motor innervation to buccinator is done with the buccal branch of CN VII but the skin is done by V3 (long buccal branch of V3).
The parotid gland duct pierces the _______ muscle.
buccinator
The _______ is the smallest skeletal muscle in the body. It attaches to the _______ to dampen vibrations from the tympanic membrane and is innervated by CN _____.
stapedius muscle, attaches to the stapes, innervated by CN VII
What are the two parasympathetic nerves associated with CN VII? What does each one do?
Greater petrosal nerve: visceral motor to the lacrimal gland and glands in mucosa of nasal cavity and palate.
Chorda tympani: visceral motor to the submandibular and sublingual glands and special sensory to the anterior 2/3 of the tongue.
Describe the pathway of parasympathetic fibers of the chorda tympani from the brainstem to its targets.
Cell bodies in the superior salivary nucleus –> piggyback CN VII motor fibers through the facial canal –> split off into the middle ear and out the petrotympanic fissure –> piggyback on the lingual nerve (V3) to the tongue (special sense anterior 2/3) or to the submandibular ganglion where synapse happens (for visceral motor to glands) –> postganglionic fiber distribution on the lingual artery to the submandibular and sublingual glands.
Describe the afferent pathway of taste fibers as they travel from the anterior 2/3 of the tongue to the brain.
Tongue –> efferent visceral motor fibers of the chorda tympani –> follow the lingual nerve for a bit, branch off –> back through the petrotympanic fissure and through middle ear –> hop on CN VII –> geniculate ganglion where taste sensory cell bodies live –> brain stem.
Describe the pathway of parasympathetic fibers of the greater petrosal from the brainstem to its targets.
Cell bodies in the superior salivatory nucleus –> piggyback CN VII motor fibers through the internal acoustic meatus –> split off anteriorly, out the hiatus for the greater petrosal n. and meet up with the DEEP petrosal nerve (postganglionic sympathetic from the internal carotid a.), forming the vidian nerve –> through the vidian canal into the pterygopalatine fossa where parasympathetics from the greater petrosal synapse at the pterygopalatine ganglion –> postganglionic parasympathetic fibers hop on V1 and V2 to go to the lacrimal gland and nasal cavity/hard palate, respectively.
Bell’s palsy is associated with a viral disease that can affect all or part of the ______ nerve. A lesion at the trunk of the nerve as it travels through the _______ _______ _______ may also cause it. Name two clinical signs of this disease.
can affect all or part of the facial nerve.
also may be caused by a lesion as the nerve travels through the internal acoustic meatus
Clinical signs:
- One side of the face droops when the patient tries to smile.
- Difficulty closing the eye on the affected side due to paralysis of the orbicularis oculi muscle.
What causes Ramsay-Hunt syndrome Type II aka herpes zoster oticus? What are six clinical features?
Reactivation of varicella virus in the geniculate ganglion of the facial nerve.
Clinical features:
- Paralysis of facial muscles unilaterally.
- Pain around one ear.
- Sounds seem louder on one side.
- Loss of taste on anterior tongue.
- Drooling out the corner of the mouth due to buccinator paralysis.
- Changes in amount of tears or saliva.
