Base of Skull/Pharynx/Retropharyngeal space Flashcards
1
Q
A
Retropharyngeal space (concern for dissection secondary to abscess)
2
Q
A
3
Q
A
4
Q
A
5
Q
ID and innervation
A
6
Q
ID and innervation
A
The cricopharyngeus m. is sometimes stretched (surgically)
7
Q
Pharyngeal plexus
A
Motor fibers are from CN X (vagus n.)
Sensory innervation fibers are from CN IX (the glossopharyngeal n.)
8
Q
ID and innervation (Superior to inferior)
A
Mid pharyngeal constrictor - connects to the hyoid bone
Constrictors are all innervated by the vagus n.
9
Q
A
Remember the lungs/trachea are anterior outpocketing of the pharynx (embryologically)
10
Q
ID and innervation
A
11
Q
ID and innervation
A
Sup. pharyngeal - anteriorly connects to buccinator with pterygomand raphe
Middle pharyngeal - connects anteriorly to the hyoid bone
Inferrior pharyngeal constrictor - connects anteriorly to the thyroid cartilage
12
Q
How to ID CN XII
A
The hypoglossal n. runs under the posterior belly of the digastric m.
13
Q
A
14
Q
A
15
Q
A
16
Q
A
Anterior scalene lives just anterior to components of the brachial plexus
The phrenic nerve lives anterior to the anterior scalene
17
Q
Whats the first sign of an acoustic neuroma?
A
Acoustic neuorma - tumor of CN VIII
Tinnitus - 1st
Balance issues - second
18
Q
A
19
Q
A
Chorda tympani runs between the handle of the malleus and the incus (internal to the malleus and external to the incus)
Goes into the anterior wall of the middle ear cavity, coming out of the petromandibular fissure right into the mandibular fossa
20
Q
Chronic middle ear infections can damage what important neurological structure?
A
The chorda tympani
21
Q
Trauma to the mandible can damage what nerve?
A
The chorda tympani - the head of the mandible can fracture the mandibular fossa, injuring the chorda tympani as it exits the petromandibular fissure
22
Q
How does the eustachian tube run?
What direction
A
From the middle ear, out the anterior wall and into the pharynx
23
Q
Tensor tympani
A
Innervated by CN V-3 (mandibular branch) and attaches to the malleus
Tenses the malleus against the tympanic membrane to dampen noise
24
Q
The stapedius m
A
Attaches to the stapes to dampen its vibrations
Innervated by CN VII
25
Where does CN IX exit the skull and enter the middle ear?
CN IX (the glosspharyngeal n.) exits the skull at the jugular foramen and enters the middle ear at the tympanic canaliculis (floor or jugular wall)
The tympanic branch of CN IX is sensory to the medial wall
Exits as the lesser petrosal branch (innervates the parotid)
## Footnote
CN's IX, X, and XI exit the jugular foramen
26
Levator palpebrae superiorosus
Skeletal muscle (proximal portion) is innervated by CN III, distal region (superior tarsal m.) is innervated by sympathetic fibers
## Footnote
Horner's syndrome - partial ptosis (injury or lesions to sympathetic chain)
27
CN IX
Tympanic branch - sensory to middle ear mucosa
Lesser petrosal branch - parasympathetic to parotid (hitchhikes on auriculotemporal branch of CN V-3)
28
CN X
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CN XI
30
CN XII
31
Superior rectus m.
32
Lateral rectus m.
33
Medial rectus m.
34
Inferior rectus m.
35
Superior oblique m.
Attaches to the posterior lateral quadrant of the globe
36
Lacrimal n.
37
Inferior oblique m.
38
Frontal n.
39
Trochlear n.
## Footnote
Only n. that originates on dorsal side of brain stem
40
If a Pt's eye is stuck in the lateral position and their CN III is completely nonfunctional, but their CN IV is functional, what will happen if you ask them to look down with the affected eye?
The eye will internally rotate
41
Nasociliary n.
Branch of CN V-1
Corneal reflex
42
Upper division of oculomotor n.
43
Lower division of oculomotor n.
Motor - inferior/medial rectus mm., and inferior oblique m
Sensory - (corneal reflex) fibers pass through ganglion and go to globe via **short ciliary nn**.
Parasympathetic - for accomodation via fibers which synapse in ciliary ganglion and go to mm of ciliary body (ball up lens) and iris (constricts pupil) via short ciliary nn
44
Where do sensory fibers for the coronary reflex arise?
CN V-1 = sensory
CN VII = motor
45
Regions of the phyarnx
A. **Nasopharynx** – base of the skull to the soft palate
B. **Oropharynx** –uvula/palate to hyoid bone
C. **Laryngopharynx** –C4-C6
46
Boundaries of the retropharyngeal space
**Anterior Boundaries **
a. Constrictor muscles-superior, middle and inferior constrictor muscles innervated by cranial nerve X,
vagus.
b. Stylopharyngeus muscle—innervated by cranial nerve IX
c. Carotid sheath
i. Internal jugular
ii. Internal carotid
iii. CN X-vagus n. (parasympathetic)
d. Sympathetic nerves (superior cervical ganglion can be found on the posterior surface of the carotid
sheath, with fibers attaching to cervical nerves 1 - 4)
**Posterior Boundary**
a. Vertebral column (bones)
b. Longus Coli m.
c. Longus Capitis m.
47
Longus capitis m
Attaches: Attaches from transverse processes of CV3-CV6 to occipital bone
§ Innervation: Cervical rami from C1-C4
§ Action: head flexion, rotate head
48
Longus coli m.
Attaches: Attaches from bodies of CV3-TV3 to transverse processes and bodies of CV2-CV6
§ Innervation: Cervical rami from C2-C6
§ Action: neck flexion, rotate neck
49
Anterior scalene
Attaches: Transverse process of CV3-CV6 to the scalene tubercle of the first rib
§ Innervation: Cervical anterior rami from C5-C8
§ Action: elevate first rib (aid in inspiration), laterally flex at neck
50
Posterior scalene m.
Attaches: Transverse process CV4-CV6 to upper surface of second rib
§ Innervation: cervical anterior rami from C6-C8
§ Action: elevate second rib (aid in inspiration), laterally flex at neck
51
Middle scalene m.
Attaches: Transverse process CV2-CV7 to upper surface of first rib
§ Innervation: cervical anterior rami from C5-C8
§ Action: elevate first rib (aid in inspiration), laterally flex at neck
52
Superior constrictor m.
Attaches: medial pterygoid plate, mandible (mylohyoid line), side of tongue to median raphe, (some fibers to pharyngeal tubercle of skull
Innervation: vagus n. (CN X)
Action: constricts upper pharynx
53
Middle constrictor m.
Attaches: greater and lesser horns of hyoid, stylohyoid ligament to median raphe
Innveration: vagus n. (CN X)
Action: constricts middle/lower pharynx
54
Inferior constrictor m.
Attaches: cricoid/thyroid cartilages to median raphe
Innveration: vagus n. (CN X)
Action: constricts lower pharynx
55
What muscle opens the eyelid?
The levator palpebrae superioris m.
56
What innervates the lacrimal gland?
The facial nerve (CN VII) via the greater petrosal n. (parasympathetic innervation)
57
What nerves that branch from the trigeminal n. innervate the eye?
Frontal - provides sensory from eye/forehead, gives rise to supraorbital and supratrochlear branches
Lacrimal - provides sensory innervation to the lacrimal gland, conjunctiva, and the lateral upper eyelid
Nascocillary - gives rise to long ciliary nerves (provid sensory innervation to the cornea) and the infratrochlear nerve (provides sensation to the medial canthus, bridge of the nose, and conjunctiva
- Anterior/posterior ethmoidal nerves provide sensory to the nasal cavity and skin on tip of nose
58
Lateral wall of the middle ear
Composed almost entirely of tympanic membrane, boundary between middle and external ear.
TM - three layered structure with epithelium externally and mucous layer internally, with some CT connecting the two, which contains microscopic nerves and vessels
The handle of the malleus attaches to the internal surface (crossed internally by the chorda tympani n.)
59
Medial wall of middle ear
Promontory - exclusion of the first rotation of cochlea (2.5 total turns)
Round window
Oval window - articulates with stapes
Tympanic plexus (mostly CN IX)
60
Anterior wall of middle ear
Tensor tympani m. (CN V-3) - attaches to the neck of the malleus - dampens movement caused by loud noises
pharyngotympanic (eustachian/auditory) tube
Sympathetic branches enter through wall foramina
Borders the interal carorid a.
Chorda tympani n. passes through the anterior canaliculus
61
Posterior wall of middle ear
Buldge from CN VII traveling the facial canal
Antrum
Pyramidal eminence with stapes m.
CN VII - chorda tympani passes through posterior canaliculus
Openings to mastoid sinus
62
What aspect of the middle ear is closes to the internal jugular vein?
A thin bone lies between the middle ear and jugular bone at the floor of the middle ear
63
What separates the middle ear cavity from the cranial cavity?
The tegmen tympani (bone at the roof of the middle ear)
64
Malleus
Articulates with the tympanic membrane and incus, has a muscle attachment to the tensor tympani (innervated by CN V-3)
65
Incus
Articulates with the malleus and stapes
66
Stapes
Articulates with incus and oval window of the inner ear, has a muscle attachement to the stapedius m. (innervated by CN VII)
67
Geniculate ganglion
Contains somatic sensory cell bodies/fibers of CN VII that carry sensory from ear and taste from tongue
68
Greater petrosal nerve
Branch of CN VII
Carries parasympathetic fibers to the lacrimal and retropharyngeal space, base of the skull, ear, nasomucosal glands
Tavels with CN V-2/V-1
69
Chorda tympani n.
Branch of CN VII
Provides taste to the tongue and parasympathetic innervation of the submandibular and sublingual glands
Travels with CN V-3
70
Sensory to the external auditory meatus
Supplied by CN V-3 (mandibular branch of trigeminal n.)
71
General sensory innervation to the middle ear mucosa
CN IX (glossopharyngeal nerve)
72
The retropharyngeal space is a potential space between the _____ and the ______
The retropharyngeal space is a potential space between the pharynx and esophagus
73
The geniculate ganglion
Sensory cell bodies of CN VII (taste, and general sensory to pinna)
CN VII parasympathetic ganglia - pterogopalantine and submandibular ganglia
74
What muscle helps open the eustachian tube?
Tensor veli palatini m. (innervated by CN V-1)
