Head and Neck Flashcards
1
Q
5 embryological parts of brain and what they form?
A
Telencephalon = cerebral hemispheres Diencephalon = Thalamus and hypothalamus Mesencephalon = Midbrain Metencephalon = Cerebellum and pons Myelencephalon = Medulla
2
Q
1st pharyngeal arch forms….
A
Muscles = TAMM --> Tensor tympani and palatini, anterior digastric, mylohyoid and masseter. PLUS MUSCLES MASTICATION. Bones = Maxilla, meckles cartilage, incus Arteries = Maxillary and external carotid Nerves = Mandibular
3
Q
2nd pharyngeal arch forms….
A
Muscles = BPPSS = Buccinator, platysma, posterior digastric, stylohyoid, stapedius (also muscles of facial expression).
Bones = Stapes, styloid process, lesser horn + upper body of hyoid. Arteries = Inferior branch of superior thyroid, Stapedial Nerve = facial
4
Q
3rd pharyngeal arch forms…..
A
Muscle = stylopharyngeus Bones = greater horn and lower body of hyoid Arteries = Common and internal carotids Nerves = Glossopharyngeal Endocrine = thymus and inferior parathyroids
5
Q
4th pharyngeal arch forms….
A
Muscles = cricothyroid, all intrinsic muscles of soft palate Bones = thyroid and epiglottic cartilage Arteries = right subclavian and left aortic arch Nerve = Vagus and superior laryngeal Endocrine = superior parathyroids
6
Q
5th pharyngeal arch forms….
A
Nothing in humans
7
Q
6th pharyngeal arch forms….
A
Muscles = intrinsic muscle of larynx except cricothyroid (CRICOTHYOID = VAGUS from 4th ARCH) Bones = Cricoid, arytenoid and corniculate Arteries = right pulmonary, left pulmonary + ductus arteriosus Nerve = Vagus and recurrent laryngeal
8
Q
Which bone contains zygomatic arch, mastoid process and contains external acoustic meatus?
A
Temporal bone
9
Q
Where does posterior digastric muscle attach to on skull?
A
Mastoid notch
10
Q
In the anterior cranial cavity is frontal crest, what attaches here?
A
Falx cerebri = specialisation of dura mater
11
Q
What sits immediately behind the frontal crest at the tip of the ethmoid bone?
What does it transmit?
A
Foramen caecum at the tip of the ethmoid bone
Transmits emissary veins connecting nasal cavity and superior saggital sinus
12
Q
What bone is below the ethmoid bone in the anterior cranial cavity, and what attaches here?
A
Below ethmoid bone = sphenoid bone
Has anterior clinoid processes = point of attachment for tentorium cerebelli
13
Q
What is tentorium cerebelli?
A
Sheet of dura separating posterior cerebral hemispheres from cerebellum
14
Q
Where do granular foveolae live and what do they do?
A
Sit either side of the groove for superior sagittal sinus, and reabsorb CSF
15
Q
In the middle cranial fossa, what makes up the sella turcica and what does it house?
A
Anterior wall = tuberculum sellae
Posterior wall = Dorsum sellae
Deep central area = hypophyseal fossa
Pituitary gland lives here
16
Q
What sits posterior to the medial part of superior orbital fissure?
What sits posterolateral and medial to this?
A
Foramen rotundum
Posteromedial = foramen lacerum
Posterolateral = Foramen ovale, and just lateral to this = spinosum
17
Q
Where does pituitary develop from?
How is it attached to hypothalamus?
A
Rathkes pouch - dépression in the wall of the pharynx
Linked to hypothalamus via infundibulum
18
Q
Which foramen are in the posterior cranial fossa?
A
Foramen magnum, internal acoustic meatus, jugular foramen, hypoglossal canal
19
Q
Bone and contents of the foramen ovale?
A
Sphenoid bone
OVALE: Otic canal V3 = mandibular Accessory meningeal artery Lesser petrosal nerve Emissary veins
20
Q
Bone and content of foramen spinosum?
A
Sphenoid bone
Middle meningeal artery = branch of maxillary artery
Meningeal branch of mandibular nerve
21
Q
Bone and content of foramen rotundum?
A
Sphenoid bone
V2 - maxillary nerve
22
Q
Bone and content of foramen lacerum?
A
Kind of know as carotid canal - immediately lateral lacerum
Sphenoid bone
Internal carotid artery
Nerve and artery of pterygoid canal
23
Q
Bone and contents of jugular foramen?
A
Temporal bone
Anterior = Inferior petrosal sinus
Intermediate = Glossopharyngeal, vagus and accessory nerves = 9/10/11
Posterior = sigmoid sinus, the meningeal branch of occipital + ascending pharyngeal arteries
24
Q
Bone and contents of foramen magnum?
A
Occipital bone
Anterior and posterior spinal arteries
Vertebral arteries
Medulla oblongata
25
Bone and content of Stylomastoid foramen?
Temporal bone
Stylomastoid artery
Facial nerve
26
Bone and content of superior orbital fissure?
Sphenoid bone
A ROOST
Abducens nerve
Recurrent middle meningeal
Occulomotor nerve - superior and inferior division
Ophthalmic nerve - Lacrimal, frontal and nasociliary
Superior ophthalmic vein
Trochlear nerve
27
Which cranial nerves have parasympathetic innervation and what do they innervate?
1973
3 = occulomtor = pupillary constriction + accommodation
7 = facial = Lacrimal gland, submandibular and sublingual
9 = Glossopharyngeal = parotid
10 = Vagus = heart and abdominal viscera
3, 7 and 9 parasympathetic innervation via head and neck = branches of trigeminal
28
How does olfactory nerve exit cranium?
Via cribriform plate of ethmoid bone
29
Where does olfactory bulb lie?
in olfactory groove in anterior cranial fossa
30
Course of optic nerve?
Enters cranium via optic canal in sphenoid bone
Runs along surface of middle cranial fossa
In middle cranial fossa optic nerves from each side unite = optic chiasm
Medial half then crosses over to contralateral sides, lateral part stays ipsilateral = optic tract
Optic tract travels to lateral geniculate nucleus in thalamus
From LGN divides into upper optic radiation via parietal lobe and lower optic radiation via temporal lobe
Both finish in visual cortex
31
Occulomotor nerve general somatic efferent supply?
Inferior, superior and medial rectus
Inferior oblique
Levator palpebrae superioris
32
Occulomotor nerve visceral efferent supply?
Sphincter pupillae = pupillary constriction
| Cilliary muscles = accommodation
33
Occulomotor nerve path?
Exits brainstem anteriorly between midbrain and pons.
Travels in tentorium cerebelli and then passes via lateral wall of cavernous sinus
Exits cranial cavity via superior orbital fissure
34
Occulomotor nerve palsy symptoms?
Down and out
Pupil fixed and dilated
Ptosis
35
Trochlear nerve somatic efferent supply, and effect this has if absent?
Superior oblique
| Vertical diplopia - cannot look down and in, head tilt away from affected side.
36
Trochlear nerve path?
Only cranial nerve to exit dorsal aspect of brainstem - midbrain.
Exits between posterior and superior cerebellar arteries
Traverses forward and enters tentorium cerebelli
Travels through lateral wall of cavernous sinus
Exits via superior orbital fissure
37
Trigeminal nerve - origin of the nerve and the sensory + motor root?
Trigeminal nerve exits via pons
Sensory root forms large crescenteric ganglion originates in Meckels cave - here the three branches exit
Motor ganglion originates in pons
38
Which branch of trigeminal carries all the motor supply?
Mandibular
39
Cranial exit of each branch of trigeminal nerve?
Standing room only
Superior orbital fissure = V1
Rotundum = V2
Ovale = V3
40
Route of ophthalmic nerve and supply?
Passes laterally in wall of cavernous sinus, to exit via superior orbital fissure
Essentially supplies sensation from anterior scalp to eyes
PURE SENSORY
41
Maxillary nerve route?
Passes in lateral wall of cavernous sinus, inferior to ophthalmic nerve
Exits via foramen rotundum and enters pterygopalatine fossa
Here it gives off several branches
Exits pterygopalatine fossa via inferior orbital fissure - becoming inferior orbital nerve
42
Branches of maxillary nerve within the pterygopalatine fossa?
Gives off zygomatic nerve, which itself gives off zygomaticofacial and zygomaticotemporal
Posterior superior alveolar nerve = supplies molar teeth
Two ganglionic branches which join with pterygopalatine ganglion
Terminal branch exits fossa via inferior orbital fissure = inferior orbital nerve
43
Maxillary nerve supply?
Sensation from lower eyelids to upper lips and mucosa
| PURELY SENSORY
44
Mandibular nerve root and branches?
Exits via foramen ovale, the motor component also exits here and joins with sensory component soon after
Soon after they join = two branches = small meningeal and nerve to medial pterygoid
Then it divides into anterior and posterior trunks
45
Anterior trunk of mandibular nerve branches + innervation?
Buccal - mainly sensory, some motor to lateral pterygoid and temporalis
Masseteric = masseter muscle
Deep temporal = temporalis
Nerve to lateral pterygoid
46
Posterior trunk of mandibular nerves branches + innervation?
1. Auriculotemporal
- sensory to temple, external ear and auditory meatus, tympanic membrane and TMJ
- delivers parasymp of CN9 via lesser petrosal nerve. This then joins with V3 to give auriculotemporal to the parotid
2. Lingual
- Anterior 2/3rds of tongue and lower oral mucosa
- Chorda tympani branch of CN7 joins = taste to anterior 2/3rds of tongue + salivary secretions
If any damage proximal to joining of Chorda tympani, then you wont lose the taste to ant 2/3rds.
3. Inferior alveolar
- Small nerve to mylohyoid + Anterior belly digastric.
Innervates all lower teeth
47
What nerve supplies the angle of the jaw?
Greater auricular nerve
48
Abducens nerve supplies what muscle?
| Pathology if damage?
Lateral rectus
Cannot abduct eye, medial deviation
Lateral diplopia
49
Path of abducens nerve?
Exits brainstem between pons and medulla
Passes via anterior wall of cavernous sinus (with ICA)
Passes over petrous bone
Exits via superior orbital fissure
50
Which pharyngeal arch does facial nerve supply?
Second
51
Which pharyngeal arch does mandibular nerve supply?
First
52
Route of the facial nerve?
motor nucleus originates from the pons, sensory from nervus intermedius
Then enters petrous bone via internal acoustic meatus with the vestibulocochlear
Here the motor and sensory combine
Passes superior to vestibule of inner ear
At medial aspect of inner widens, and becomes geniculate ganglion
Exits via the stylomastoid foramen
Then enters the parotid gland to give its 5 terminal branches
53
Branches of the facial nerve and where?
As it becomes geniculate ganglion near inner ear = three branches:
Chorda tympani, greater petrosal and nerve to the stapedius
As it exits temporal bone via stylomastoid foramen = 2 branches:
Posterior digastric muscle (also supplies stylohyoid) and posterior auricular nerve (occipital belly of occipitofrontalis).
Enters parotid - Temporal, zygomatic, buccal, marginal mandibular and cervical
54
Buccal branch muscles?
ZORB LN
```
Zygomaticus minor - Elevates upper lip
Orbicularis - Close and tighten lip
Risorius - Aids smile
Buccinator - Pulls corner of mouth back
Levator anguli oris - Pulls angle of mouth up
Nasalis - flares nostrils
```
55
Branches of mandibular nerve
MALIN
```
Mental
Auriculotemporal
Lingual
Inferior alveolar
Nerve to mylohyoid
```
56
Route of vestibulocochlear nerve?
Exits brainstem at cerebellopontine angle between pons and. medulla at cerebellopontine angle.
Within the pons the vestibular and cochlea components join
Exits cranium at internal acoustic meatus(with the facial nerve).
In distal part of this splits into the V + C components again
57
which pharyngeal arch does the glossopharyngeal come from and which muscle does it innervate?
3rd pharyngeal arch = stylopharyngeus
58
Route of the glossopharyngeal nerve?
Several nerve roots from medulla
These pass through and join in jugular foramen
Just as it exits jugular foramen it gives off tympanic nerve = enters middle ear and joins tympanic plexus
The lesser petrosal nerve arises from the tympanic plexus -- supplies parasympathetic to otic ganglion. This goes on to give the auriculotemporal which is joined by V3 to supply parotid.
59
Course of right vagus nerve ?
```
lateral medulla, jugular foramen.
Then contained in own dural sheath alongside accessory nerve
Descends in neck in carotid sheath.
- Medial to IJV
- Posterior to CC and IC
```
Anterior to 1st part of subclavian artery
Passes posterior to lung root
Forms vagal plexus inferiorly
Pass via oesophageal hiatus
60
Course of left vagus nerve?
```
lateral medulla, jugular foramen.
Then contained in own dural sheath alongside accessory nerve
Descends in neck in carotid sheath.
- Medial to IJV
- Posterior to CC and IC
```
Passes between subclavian artery and common carotid
Passes posterior to lung root
Forms vagal plexus inferiorly
Pass via oesophageal hiatus
61
What are the superior and inferior cervical cardiac nerves branches of, and what is their root?
Vagus
Right they pass posterior to subclavian artery
left superior - passes between aortic arch and trachea
Left inferior - descends with vagus itself
62
Course of right recurrent laryngeal vs left?
Right branches off and hooks under subclavian artery, ascending alongside trachea to insert in larynx
Left branches off and hooks under aortic arch, behind ligaments arteriosum and supplies larynx
- Left can be injured in thyroid surgery
63
Why is accessory nerve unique, and what does it innervate?
Arises from upper 5 cervical segments
Trapezius and sternocleidomastoid
64
Route of accessory nerve?
Arises from upper 5 C-spines, ASCENDS via foramen magnum, moves posteriorly and descends via jugular foramen
Fibres pass over transverse process of atlas = here it is crossed by occipital artery
Then descends medially to styloid process, stylohyoid and posterior belly of digastric
Then enters sternocleidomastoid at upper surface, leaves it posteriorly at midpoint
Travels along surface of levator scapulae
In close proximity to superficial cervical LN's
65
Hypoglossal nerve route?
Arises from pre-oliviary sulcus of medulla
Passes via hypoglossal canal
Lies on the carotid sheath, looping under the occipital artery.
Passes deep to the posterior belly of digastric
Then passes under stylohyoid muscle.
66
Hypoglossal supplies all muscle of tongue except which muscle?
Palatoglossus = VAGUS
67
Where does the common carotid bifurcate?
level of upper thyroid = C3/4
68
Does the cervical sympathetic chain lie anterior or posterior to the CCA?
Posterior
69
Route of the left common carotid vs right?
LEFT:
Arises immediately lateral to brachiocephalic direct from aorta.
Brachiocephalic vein passes anteriorly
Inferior thyroid artery posteriorly
It is in contact with trachea, left margin of oesophagus and left recurrent laryngeal
In the neck It runs superiorly, deep to sternocleidomastoid
Enters anterior triangle and the carotid sheath
Sits with vagus and IJV ---> IJV = lateral, vagus posterior
At C6 = crossed by omohyoid, and passes anterior to carotid tubercle
At C7 thoracic duct and vertebral artery lie behind it
Right is similar except arises directly from brachiocephalic
No thoracic duct on the right
Crossed by recurrent laryngeal posteriorly
70
What is the route of each vertebral artery?
Arises from 1st part of subclavian artery
Enters cranial cavity via foramen magnum, running through foramina of transverse processes of upper 6 cervical vertebrae
Runs posteromedially on axis, and then enters sub occipital triangle and enters vertebral canal.
Lies in subarachnoid space
Ascends on antero-lateral medulla surface
Unites to form basilar artery at base of pons
71
Branches of the vertebral artery?
Posterior and anterior spinal arteries
| Posterior inferior cerebellar artery
72
Branches of the basilar artery?
Caudal to rostral:
1. Anterior inferior cerebellar
2. Labyrinthine = accompanies CN7/8 into internal acoustic meatus
3. Pontine
4. Superior cerebellar = can be decompressed to treat trigeminal neuralgia
5. Posterior cerebral = oculomotor + trochlear nerve lies between this and superior cerebellar.
- Supplies occipital lobe and part of temporal
73
What are your branches of the internal carotid?
```
Anterior cerebral
Middle cerebral = brocas
Posterior communicating
Anterior choroidal
Ophthalmic
Meningeal + hypophyseal
```
74
Nerves at risk during carotid endarterectomy?
hypoglossal, greater auricular and superior laryngeal
75
What layer do the dural sinuses lie within?
| Valves or not?
Between the periosteal layer and meningeal layer of dura mater
No valves
76
Superior sagittal sinus location and path?
Superior surface of falx cerebri
Begins at foramen caecum - can receive emissary veins from nasal sinus
Ends posteriorly in confluence of sinuses
77
Inferior sagittal sinus route, what joins with it to form what?
Begins at inferior border of falx cerebri
Travels posteriorly to end at anterior edge of tentorium cerebelli where it is joined by great cerebral vein
Becomes straight sinus - continues posteriorly
78
Where does confluence of sinuses lie?
Dilated space at internal occipital protuberance
79
What sinus extends laterally from the confluence of sinuses, and what does each one receive?
The transverse sinuses
Right receives superior saggital sinus
Left receives straight sinus
80
what do the transverse sinuses become as they leave occipital bone, and in turn what do these become?
Become the sigmoid sinus, which becomes the IJV
81
Which sinus sits either side of sella turcia, what does it receive from and which structures pass through it?
Cavernous sinus
Receives from - Cerebral, ophthalmic and emissary veins
Structures passing THROUGH = ICA and abducens
Structures in LATERAL WALL = superior to inferior: OTOM
1. Occulomotor (3)
2. Trochlear (4)
3. Ophthalmic (V1)
4. Maxillary (V2)
Or its just the nerves 3,4,5a/b
Then passing through is nerve 6
82
What drains the cavernous sinus into the sigmoid sinus?
Inferior and superior petrosal sinuses
83
Tributaries into the internal jugular vein?
```
Pharyngeal
Common facial
Occipital
Lingual
Superior thyroid
Middle thyroid
External jugular
```
84
Three layers of the meninges?
tough outer layer = dura mater
Delicate inner layer = arachnoid mater
Inner layer firmly attached to brain = Pia mater
85
Are your cranial meninges continuous with the spinal meninges?
Yes
| Apart from dura mater, which has two layers and only the inner meningeal is continuous through the foramen magnum
86
What are the three dural partitions, where they begin and end and what they separate?
Falx cerebri - separates cerebral hemispheres
- Begins anteriorly at frontal crest, joins with tentorium cerebelli posteriorly
Tentorium cerebelli - Separates cerebral hemispheres from cerebellum
- Begins anteriorly at clinoid process for sphenoid bone, finishes posteriorly in groves for transverse sinus
Falx cerebelli - separates cerebellar hemispheres
87
Arterial supply to dura mater In anterior fossa?
Anterior meningeal artery = branch of ethmoidal arteries
88
Arterial supply to dura mater in middle cranial fossa?
Middle meningeal = branch of maxillary, enters via foramen spinosum
accessory meningeal = small branch of maxillary, enters via foramen ovale
89
Arterial supply to dura mater in posterior cranial fossa?
Posterior meningeal = terminal branch of ascending pharyngeal, via jugular foramen
A meningeal branch from ascending pharyngeal also enters via hypoglossal canal
Meningeal branch from occipital via jugular foramen and mastoid foramen
Meningeal branch from vertebral artery via jugular foramen
90
Which pharyngeal arch do all the facial muscle come from, and which nerve supplies them?
How can we classify facial muscles?
2nd pharyngeal arch = facial nerve
Orbital, nasal and oral group
91
Muscles not defined as facial muscle but from 2nd pharyngeal arch?
Platysma: Tenses skin of neck and moves lower lips down
Origin = below clavicle
Insertion = Medial fibres on mandible, lateral fibres join muscles around mouth
Occipitofrontalis
Frontal belly = anterior covers forehead and attaches to skin of eyebrows
Occipital belly = arises from posteiror aspect of the skull
Moves the scalp and wrinkles forehead
Insertion for both = galea aponeurotica
Occipital belly = posterior auricular nerve
92
Course of salivary duct?
Crosses masseter, pierces buccinator, drains adjacent to 2nd upper molar = stensens duct
93
Structures passing through the parotid gland?
FEAR
Facial nerve - all branches except mandibular
External carotid artery
Auriculotemporal nerve
Retromandibular vein = superficial temporal and maxillary vein combine
94
Lymphatics and innervation of parotid gland?
Lymphatics = deep cervical
Innervation:
Sensory = auriculotemporal
Parasymp:
- Begins in the inferior salivary nucleus. Exits medulla as CNIX
- Then forms inferior ganglion. Typmanic nerve leaves this. Forms tympanic plexus.
- in tympanic plexus in middle ear branches to lesser petrosal --> otic ganglion
- Post-ganglionic it is via auriculotemporal nerve, where it is joined by V3.
95
Branches of the ophthalmic nerve?
Supra-orbital and supra-trochlear nerves:
Exit orbit superiorly to supply upper eyelid, forehead and scalp
Infratrochlear exits orbit medially = innervates medial half of upper eyelid and side of nose
lacrimal nerve = exits orbit laterally = lateral half of upper eyelid
External nasal nerve = anterior nose
96
What is the posterior auricular a branch of, where does it branch and what does it supply?
Facial nerve
Branches as the facial nerve passes through stylomastoid foramen, to exit temporal bone
Supplies occipital belly of occipitofrontalis and posterior auricular muscle
97
Arterial supply to the face - four main arteries?
Facial artery = branch of external carotid, passes through deep structures of the neck, posterior to submandibular gland.
- terminates at medial eye as angular artery
Transverse facial artery = branch of superficial temporal = terminal branch of external carotid
- Arises within parotid
Maxillary artery = larger terminal branch of external carotid
Ophthalmic artery = Branch of ICA
Three small branches: zygomaticofacial, zygomaticotemporal + dorsal artery
98
Venous drainage of face?
Facial vein:
- Supratrochlear and supraorbital form the angular vein
- this becomes the facial vein
- Facial vein lies posterior to facial artery, until it reaches inferior mandible and it passes superficially over the submandibular gland (vs. artery passing posterior)
99
Lacrimal gland innervation?
Facial nerve gives off the greater petrosal nerve which goes to the pterygopalatine ganglion
Post-ganglionic = joins with nerve fibres of maxillary nerve to form zygomatic nerve.
This joins with lacrimal nerve to innervate lacrimal gland
100
Vasculature of lacrimal gland?
Ophthalmic artery and vein
101
Fissures and foramina of orbit?
Superior orbital fissure = A ROOST
Inferior orbital fissure = Maxillary nerve + zygomatic branch, infra-orbital vessels
Optic canal = optic nerve and ophthalmic artery
102
Extrinsic eye muscles - innervation and action, and origin /insertion
All occulomotor except SO4 LR6
Levator palpebrae superioris = Elevates upper eyelid
- Origin = lesser wing of sphenoid
Insertion = tarsal plate
- superior branch of occulomotor
Superior rectus = Elevates and adducts eye
- Origin = Superior part of common tendinous ring
- Inserts = anterior eyeball superiorly
- Superior branch of occulomotor
Inferior rectus = depresses eye and adducts
- origin = inferior common tendinous ring
- insertion = anterior half of eyeball inferiorly
- Superior branch of occulomotor
Medial recuts = adducts
- Origin = medial common tendinous ring
- insertion = Medial anterior eye
- inferior branch occulomotor
Inferior oblique = adducts and elevates = up and in
- origin = medial floor of orbit
- insertion = outer posterior quadrant of eye
- inferior occulomotor
LR = abducts
- Origin = lateral common tendinous ring
- insertion = lateral anterior eyeball
- abducens
SO = down and out
- origin = Body oh sphenoid
- insertion = posterior puter quadrant
- trochlear nerve
103
2 intrinsic muscles of the eye?
Sphincter pupillae - constricts pupil = occulomotor
Dilator pupillae - dilates pupil = superior cervical ganglion
104
lymphatic drainage of external ear?
Lower part = superficial cervical
Upper lateral part = superficial parotid
Medial upper part = mastoid and deep cervical
105
Innervation of external ear?
Auriculotemporal, greater auricular ands occipital nerve
106
Layers of tympanic membrane?
Externally = stratified squamous epithelium
Then fibrous layer
internally = mucous membrane continuous with middle ear
107
Innervation of tympanic membrane?
Inner part = glossopharyngeal nerve
| Outer part = Auriculotemporal nerve
108
Order of middle ear bones?
Tympanic membrane > malleus (via umbo) > incus > stapes > oval window
109
Which nerve innervates middle ear and clinical relevance?:
Glossopharyngeal
| Means after tonsillectomy / tonsillitis may get ear pain
110
Does Chorda tympani pass medial or lateral to pars flaccida?
| and where does Chorda tympani come from?
Medial to pars flaccida
It is a branch of the facial nerve once it widens in the middle ear to become geniculate ganglion
111
How does middle ear communicate with nasopharynx?
Pharyngotympanic tube anteriorly
112
Arterial supply of middle ear?
Venous supply?
2 arteries:
Tympanic branch of maxillary artery
Mastoid branch of occipital / posterior auricular
Venous = pterygoid plexus and superior petrosal sinus
113
2 muscles of the middle ear, innervation and role?
Tensor tympani:
- mandibular nerve of trigeminal
- contraction causes the handle of malleus to move medially which tightens tympanic membrane = dampens loud noises
Stapedius:
- Facial nerve
- Pulls stapes posteriorly in response to loud noise = prevents excessive oscillation
114
Innervation of inner ear and closely related nerve?
Vestibulocochlear
Facial closely related - enters inner ear with it via internal acoustic meatus, where it then enters facial canal and enlarges to become geniculate ganglion
At geniculate it gives off greater petrosal nerve
Then goes on to give off stapedius and then Chorda tympani
Exits skull via stylomastoid foramen.
115
Branches of maxillary artery?
First part - sits below auriculotemporal nerve and runs along lower border of lateral pterygoid:
- Middle meningeal
- Inferior alveolar
- Deep auricular, anterior tympanic, accessory meningeal
Second part - Runs underneath ramus of mandible and insertion of temporalis. Runs along superficial surface of lateral pterygoid before passing between two heads:
- Deep temporal
- Masseteric
- Buccal
- Pterygoid
116
Fascial layers of the neck?
Superficial fascia - contains platysma
Pre-vertebral - contains scalene muscles and deep muscles of back
- also extends to form axillary sheath, which covers
brachial plexus and axillary artery
Pre-tracheal fascia - covers oesophagus, trachea and thyroid
Carotid sheath = IJV, ICA / CCA and vagus
117
Superficial drainage of the neck?
What forms retromandibular vein?
Via external jugular vein:
Formed from joining of retromandibular and posterior auricular veins
Once formed it travels in superficial fascia
Passes superficial to sternocleidomastoid, passing posterior to it just superior to clavicle
Here it pierces cervical fascia
Passes deep to clavicle and enters subclavian
*Retromandibular vein formed from superficial temporal and maxillary veins*
118
Borders of anterior triangle of neck + subdivisions of this?
Anterior border of sternocleidomastoid
Midline of neck
Inferior border of mandible
Submental, submandibular / digastric, carotid and muscular triangles
119
Border and contents of submental triangle?
Anterior belly digastric, hyoid bone and anterior midline
120
Border and contents of submandibular/digastric triangle?
Anterior and posterior digastric and inferior mandible
Submandibular nodes and glands, facial vessels and hypoglossal
121
Border and contents of carotid triangle?
Anterior sternocleidomastoid, Superior omohyoid and posterior digastric belly
Carotid sheath and ansa cervicalis
122
Border and contents of muscular triangle?
Hyoid bone, superior belly of omohyoid + anterior sternocleidomastoid
Strap muscles and external jugular vein
123
Muscles of the anterior triangle can be divided into two groups, and what muscles are in these groups?
Suprahyoid = Stylohyoid, digastric, mylohyoid, geniohyoid
Infrahyoid = Thyrohyoid, omohyoid, sternohyoid, sternothyroid (TOSS)
124
Innervation of posterior digastric vs anterior digastric?
Posterior = facial nerve branch, as it leaves stylomastoid foramen
Anterior branch = mylohyoid branch of inferior alveolar = mandibular posterior trunk branch
125
External carotid path?
Divides at C3/C4 from common carotid
Ascends anterior to internal carotid and posterior to post. belly of digastric and stylohyoid.
Pierces the fascia of parotid gland, and within parotid divides into its 2 terminal branches - maxilla and superficial temporal
126
Branches of external carotid from inferior to superior?
```
Superior thyroid
Ascending pharyngeal
Lingual
Facial
Occipital
Posterior auricular
Maxillary
Superficial temporal
```
127
Ansa cervicalis - relation to IJV in sheath, what it supplies + how to get to it fascia wise?
superficial to IJV in carotid sheath
Supplies infra hyoid muscles except thyrohyoid
Must divide pre-vertebral fascia to expose it
128
When dividing strap muscles to expose a large goitre where must you divide?
You most divide them superiorly as the ansa cervicalis enters at the inferior aspect of the muscles
129
Thyroid origin and what structure marks course?
Foramen caecum = origin
| Thyroglossal duct = path of descent
130
Which fascia surrounds thyroid and parathyroid?
Pre-tracheal fascia
Clinically relevant as it is an unforgiving fascia = can form tense haematoma post-thyroid surgery
131
Relations of the thyroid - anteriorly, posteriorly, medial + lateral
Anterior = infra hyoid muscles except thyrohyoid, anterior sternocleidomastoid
Posterior = parathyroid glands, anastomosis of superior and inferior thyroid arteries
Medial = trachea, larynx, pharynx, oesophagus, Cricothyroid. Also external and recurrent laryngeal
Lateral = carotid sheath
132
Arterial supply of thyroid?
Superior thyroid artery = 1st branch of ECA
Inferior thyroid artery = branch of thyrocervical trunk = branch of subclavian. Enters thyroid at C6
- has inferior branch which supplies lower thyroid and
anastomoses with posterior branch of superior thyroid artery
- Ascending branch supplies parathyroids
thyroid ima - 10% of population, directly from brachiocephalic / aorta
133
Venous supply of thyroid?
superior and middle thyroid veins directly to IJV
| Inferior thyroid vein to brachiocephalic
134
Embryology of parathyroids?
inferior ones from 3rd pharyngeal arch - can be associated with thymus
Superior ones with 4th pharyngeal arch, can be associated with thyroid
135
Vasculature of parathyroids?
| How does arterial supply ever the parathyroid?
Arterial supply is ascending branch of inferior thyroid.
Enters MEDIALLY
Venous is via thyroid veins
136
Borders of posterior triangle?
Posterior sternocleidomastoid
Lateral clavicle
Anterior trapezium
137
Contents of posterior triangle?
```
Muscles = Traps, sterno, splenius capitis and the scalenes
Vessels = thyrocervical trunk, external jugular vein and subclavian
Nerves = accessory nerve and cervical plexus
LN's = supraclavicular and occipital
```
138
Muscles of posterior triangle: Origin, insertion, function and innervation?
Trapezius = elevate, adduct and depress scapula
- Accessory
- origin = superior nuchal line + spinous processes C7 - T12
- insertion = Lateral third of clavicle, spine of scapula
Sternocleidomastoid = tilt head ipsilaterally
- accessory
- Origin = upper sternum and medial clavicle
- insertion - Lateral half of nuchal line + lateral mastoid process
Splenius capitus = together draw head back, individually move head ipsilaterally
- posterior rami of cervical nerves
- origin = lower half of ligaments nuchae, spinous process of C7 - T4
Insertion = Mastoid process and skull below nuchal line
Posterior scalene = elevates rib 2
- Anterior rami of C5-C7
- Origin = transverse process of C4-C6
- insertion = rib 2
Middle scalene = elevates rib 1
- Anterior rami of C3-C7
- origin = transverse process of C2- C7
- Insertion = rib 1
Anterior scalene = elevates rib 1
- Anterior rami of C4 - C7
- Origin = C3-C6
- Insertion = Rib 1 and scalene tubercle
139
Vessels of posterior triangle in neck?
External jugular vein = joining of retromandibular and posterior auricular
Thyrocervical trunk = branch of subclavian artery = inferior thyroid, suprascapular and transverse cervical
- All pass anterior to anterior scalene
Subclavian:
- 1st part = ascends to medial border of anterior scalene
- 2nd part passes between anterior and middle scalene
- 3rd part = emerges from between the two. Becomes axillary artery at lateral border of first rib.
140
Nerves In posterior triangle of the neck?
LN's of posterior triangle?
Accessory nerve = passes deep to sternocleidomastoid
Cervical plexus from C2-C4 anterior rami
Supraclavicular and occipital
141
Branches of subclavian artery?
VITC+D
```
Vertebral arteries
Internal thoracic
Thyrocervical trunk
Costocervical
Dorsal scapular
```
142
Internal thoracic and costocervical trunk: routes + what are they branches of?
branches of subclavian artery
Internal thoracic = Passes posterior to the clavicle, enters thoracic cavity anterior to thoracic transversus muscle
Costocervical:
- on left arises from 1st part fo subclavian, medial to anterior scalene
- on right arises from second part
- both sides it ascends superiorly over dome of lung behind anterior scalene
143
Nerves of the root of the neck and their course?
Phrenic:
Passes with. IJV on anterior scalene, then passes deep to deep vertebral fasica
LEFT:
Passes over 1st part of subclavian artery, runs between subclavian artery and vein.
Runs laterally to left subclavian, aortic arch and LV
Then passes anterior to root of lung, piercing diaphragm solo
RIGHT:
Passes over second part of subclavian artery, running between the subclavian artery and vein.
Runs anterior to right vagus and lateral to SVC, to the right of the pericardium.
Passes over right atrium, exiting diaphragm at T8
Recurrent laryngeal = branch of vagus
Right hooks under subclavian artery
Left hooks under aortic arch
Sympathetic trunks
144
What are the 3 Sympathetic trunks of the root of neck and what they supply?
Superior cervical ganglion = superior cardiac nerves + surrounds carotid arteries
Middle cervical ganglion = C5 + C6, middle cardiac nerves
Inferior cervical ganglion = C7-T1, plexus around vertebral artery + inferior cardiac nerves
145
Where thoracic duct joins left brachiocephalic what are the three confluences and their drainage?
Right sided equivalent?
Left jugular trunk = head and neck
Left subclavian trunk = Left upper limb
Left bronchomediastinal = Left half of thoracic structures
Right side has same confluence but they go directly into brachiocephalic in right
146
Relations of thoracic duct and its route?
```
Anterior = oesophagus
left = thoracic aorta
Right = azygous vein
```
At T5 passes to left of oesophagus, passing behind the carotid sheath but in front of:
- thyrocervical trunk
- phrenic
- vertebral artery
147
Where does pharynx begin an end?
Base of skull down to the b beginning of the oesophagus at cricoid cartilage (C6)
148
What separates the oropharynx and laryngopharynx?
Epiglottis
149
How do you divide up the two sets of muscles in the pharynx, origin and insertions and their innervation?
Constrictor muscles = Circumferential fibres. All insert posteriorly into pharyngeal raphe
- Superior constrictor = pterygomandibular raphe
- middle constrictor = hyoid bone
- inferior constrictor = cricoid and thyroid cartilage
Longitudinal muscles = all elevate pharynx, and all insert into pharyngeal wall
- Stylopharyngeus = medial styloid process
- Salpingopharyngeus = inferior to opening of pharyngotympanic tube
- Palatopharyngeus = Palatine aponeurosis
ALL INNERVATED BY VAGUS, except Stylopharyngeus = glossopharyngeal
150
Sensory supply to pharynx?
```
Nasopharynx = V2
Oropharynx = vagus via pharyngeal plexus
Laryngopharynx = Vagus via superior laryngeal
```
151
Vasculature of pharynx?
Lymph drainage?
superior pharynx = branches of external carotid artery
Inferior pharynx = Pharyngeal branches of inferior thyroid artery from thyrocervical trunk
Venous = Pterygoid plexus
LN's = deep cervical nodes
152
Tonsils:
Arterial supply?
Venous supply?
LN's?
Tonsillar artery = branch of facial
Venous = its veins pierce the constrictor muscles to join either external palatine or facial veins
LN's = jugulodigastric and deep cervical
153
Tonsillectomy:
Indications?
What is damaged if haemorrhage?
Indications. = suspected malignancy, recurrent tonsillitis, causing sleep apnoea
External palatine vein lies laterally = can be damaged in tonsillectomy
154
Innervation of the laryngeal muscles?
All by the recurrent laryngeal, except the Cricothyroid = external laryngeal (branch of superior laryngeal from vagus)
155
Muscles of the larynx - origin and insertion?
Posterior cricoarytenoid
- Origin = Posterior cricoid
- insertion = muscular process of arytenoid
Lateral cricoarytenoid
- Origin = Arch of cricoid
- Insertion = Muscular process of arytenoid
Thyroarytenoid
- origin = posterior thyroid cartilage
- insertion = muscular process of arytenoid
Transverse and oblique arytenoids
- Origin = Arytenoid cartilage
- insertion = contralateral arytenoid
Vocalis
- origin = depression in lamina of thyroid cartilage
- insertion = Vocal ligament/process of arytenoid
Cricothyroid
- origin = cricoid anterolaterally
- insertion = inferior and horn of thyroid cartilage
156
Arterial supply of the larynx?
Which one of these is closely related to the internal laryngeal nerve, and where does it pass through?
Superior laryngeal artery = branch of superior thyroid artery via external carotid
Inferior laryngeal artery via inferior thyroid artery via thyrocervical trunk
Superior laryngeal nerve is closely related to the internal laryngeal nerve, and together they pierce the thyrohyoid membrane
157
Venous drainage of the larynx?
Superior laryngeal vein into superior thyroid vein to IJV
Inferior laryngeal vein into middle thyroid artery into IJV
158
LN's of larynx?
Above vocal cord = deep cervical
| Below vocal cord is ones associated with inferior thyroid artery
159
What cell type is inner larynx, and what is vocal cords?
Inner larynx = ciliated pseudostratified columnar
| Vocal cords = stratified squamous
160
Nerve supply of larynx?
Superior laryngeal nerve:
- Descends medial to ICA and divides into external and internal just above hyoid bone
- Internal = sensory to vocal cords. Pierces thyrohyoid membrane with superior laryngeal artery
- External = penetrates inferior constrictor of pharynx. Supplies cricothyroid
161
Arterial supply of the nose?
Venous drainage?
Comes from internal carotid = anterior and posterior ethmoidal via ophthalmic artery
External carotid:
Maxillary artery gives Sphenopalatine + greater palatine
Facial gives Superior labial + lateral nasal
Pterygoid plexus, anterior region can also drain via facial vein
162
Route of the arteries to the nose from external carotid?
Route of the arteries to the nose from internal carotid?
Sphenopalatine:
- Branch of maxillary, exits pterygopalatine fossa and enters nasal cavity via sphenopalatine fossa
- Supplies lateral wall via posterior nasal branch, and medial wall via posterior septal branch
Greater palatine:
- branch of maxillary within the pterygopalatine fossa
- enters nasal cavity via incisive canal
- supplies anterior media part of the wall
Superior labial and lateral ansal:
- Branch of facial
- Labial = lips and nose, nasal = external nose
Anterior and posterior ethmoidal:
- From ophthalmic artery
- Posterior enters via cribriform plate
- anterior accompanied anterior ethmoidal nerve along groove of cribriform plate and enters via foramen lateral to cristal galli
163
Which arteries from a major anastomosis in the nose?
Sphenopalatine, anterior ethmoidal, greater palatine and superior labial = SAGS
This can be site of major epistaxis
164
Nerve supply to nasal cavity?
Which does the anterior ethmoidal artery travel with?
special afferent = olfactory
Maxillary = sensory:
- Enters via sphenopalatine fossa
- lateral wall and septum
Ophthalmic = sensation:
- Anterior ethmoidal - travels forward in groove of cribriform plate, enters nasal cavity via foramen lateral to Cristal galli with anterior ethmoidal artery
165
What does the anterior ethmoidal artery terminate as and supply?
External nasal nerve = tip of nose
166
Lymphatics of nose?
```
Anterior = submandibular
Posterior = deep cervical
```
167
Innervation of muscles of tongue?
All supplied by hypoglossal EXCEPT Palatoglossus = vagus nerve
168
Veins of the tongue?
Dorsal lingual vein:
- Travels with lingual nerve
- Deep to hyoglossus, on top of the genioglossus
- Pass out via aperture of mylohyoid, middle and superior constrictor - to IJV
Deep lingual vein:
- Passes over external surface of hyoglossus, beneath genioglossus.
- Travels with hypoglossal nerve
- Drains into IJV
169
Arteries of the tongue?
Main on is lingual artery from external carotid, adjacent to greater horn of hyoid
- Enters cavity via aperture formed from mylohyoid, superior and middle constrictor
- Passes deep to hyoglossus
- Then travels forward between hyoglossus and genioglossus
170
Innervation to the tongue?
Sensory:
Anterior 2/3rds = mandibular via lingual
posterior 1/3rd = glossopharyngeal
Taste:
Anterior 2/3rds = facial
Posterior 1/3rd = glossopharyngeal
171
Route of hypoglossal, glossopharyngeal and lingual nerve to the tongue?
Hypoglossal:
- Innervates all muscles except palatoglossus
- Leaves skull via hypoglossal canal
- At angle of mandible, arches sharply forwards under occipital artery (sternocleidomastoid branch)
- Travels superficial to ECA/ICA
- Follows root of deep lingual vein over the hyoglossus
Glossopharyngeal:
- Leaves skull via jugular foramen + descends along posterior stylopharyngeus
- Then slips through aperture created by mylohyoid and middle/superior constrictors
- Is deep to hyoglossus
Lingual:
- Passes beneath superior constrictor
- continues forward and passes under submandibular gland
- Ascends in tongue on superior hyoglossus
- Closely related to third molar
172
If you extract the 3rd molar, what nerve may be affected and symptoms?
Lingual nerve
| Paraesthesia on anterolateral tongue
173
Lymphatics of tongue?
```
Tip = submental
Middle = submandibular
```
Both then go to deep cervical LN's.
```
Anterior = ipsilateral
Posterior = bilateral spread
```
174
What sits superficial and deep to submandibular gland?
Superficial = Facial vein and artery, marginal mandibular nerve + cervical branch of facial, Platysma
Deep = Facial artery below mandible, Lingual and hypoglossal nerve
175
Whats the best access for submandibular gland surgery?
3cm below mandible = avoid transection of marginal mandibular nerve
176
Vessels and lymphatics of submandibular gland?
Facial artery and vein
LN's = deep cervical and jugular
177
Parasymp. innervation of submandibular gland?
Superior salivary nucleus
Chorda tympani via facial nerve
Joins onto lingual nerve
178
Common cell type found in parathyroids?
Oxyphill
179
Arterial and venous supply of the teeth?
Arterial = branches of the maxillary artery
Superior alveolar = upper teeth
Inferior alveolar = lower teeth
Venous maps this -> pterygoid plexus
180
Innervation of teeth?
Upper teeth = branch of maxillary nerve = Anterior/posterior/middle superior alveolar branches
lower teeth = mandibular nerve = inferior alveolar nerve
- This divides next to first pre-molar into incisive and mental branches
181
Thymus - cellular arrangement?
Has cortex = tightly packed lymphocytes
| Has medulla = epithelial cells, arranged around keratinised Hassall's corpuscle
182
Thymus arterial and venous supply?
Arterial = Internal mammary + pericardiophrenic
Venous = left brachiocephalic
183
Draw the cranial fossa and the foramen - labelling each one and its contents.
See notes.
184
Bones and contents of internal acoustic meatus?
Temporal bone
Facial nerve
Vestibulocochlear nerve
Labrynthine artery
185
Bone and contents of optic canal?
Sphenoid bone
Optic nerve
Ophthalmic artery
186
How does the facial nerve go via the Internal acoustic meatus AND stylomastoid foramen?
Nerve arises In the pons - two roots a motor and sensory.
The two roots travel via the internal acoustic meatus.
Still within the temporal bone they exit the IAM and 3 big things happen:
1. two roots fuse = facial nerve
2. next the nerve forms geniculate ganglion
3. Gives off three branches = greater petrosal, Chorda tympani and nerve to stapedius
Then exits cranium via stylomastoid foramen.
187
Orbital group of face muscles (2)?
Orbicularis oculi = close eyelids
Two major parts outer orbital part, inner palpebral part
Origin = medial palpebral ligament
Palpebral part finishes lateral ralphe, orbital part is continual orbit.
Corrugator supercilli = draws eyebrow to midline, wrinkling above nose
Origin = medial end of superciliary arch
Inserts = skin medial half of eyebrow.
188
nasal group of facial muscles (3)
1. nasalis = flares and closes nasal aperture.
Alar part flares. originates maxilla below, inserts alar cartilage.
Transverse part decompresses. Origin maxilla, inserts aponeurosis across dorsum of nose
2. Procerus = brings medial eyebrow down and wrinkles nose.
Origin = nasal bone
Inserts skin lower forehead.
3. Depressor septi nasi = widens nostrils
Origin = maxilla insertion = lower part of septum.
189
Oral group facial muscles (4)?
1. Orbicularis oris = narrows mouth e.g. whistling
Origin - buccinator, some maxilla superiorly and mandible inferiorly
Insertion = ski and mucous membranes of lips
2. Buccinator = Contracts cheeks against teeth
Origin = posterior maxilla and mandible
Insertion. = corner of lips and blends with orbiculares oris
3. Lower group oral muscles
4. Upper group oral muscles
190
Muscles of mastication (4)?
What innervates them all?
1. Masseter = elevates mandible
Origin = zygomatic arch and maxillary process of zygoma
Inserts = lateral mandible
2. Temporalis = elevates and retracts mandible
Origin = bone of temporal fossa
Insertion = Mandible
3. Medial pterygoid = elevates and lateral movement of mandible
Origin = Deep head > medial pterygoid process. Superficial head = tuberosity of maxilla.
Insertion = medial mandible
4. Lateral pterygoid = protrusion and lateral mandible movement
Origin = upper head > infra temporal fossa. Lower head > lateral pterygoid.
Insertion = TMJ and neck of mandible.
ALL INNERVATED BY MANDIBLE
191
Suprahyoid muscles?
1. Stylohyoid = elevates hyoid bone
Origin = base of styloid process
Insertion = lateral hyoid bone
Facial Nerve
2. Posterior digastric = pulls hyoid bone up and back
Origin = mastoid process temporal bone
Insertion as above
Facial nerve
3. Digastric anterior belly = Lowers mandible
Origin = Lower mandible
Insertion = tendon of hyoid bone
Mylohyoid nerve from inferior alveolar of mandibular
4. Mylohyoid = Elevate floor of mouth
Origin = mylohyoid line on mandible
Insertion = body of hyoid bone
Mylohyoid nerve
5. Geniohyoid = Elevate hyoid or pull mandible down
Origin = mandible
Insertion = Anterior hyoid
Anterior ramus C1 via CNXII
192
Infrahyoid muscles?
1. Thyrohyoid = depresses hyoid and raises larynx.
Origin = thyroid cartilage
Insertion = Body of hyoid
Anterior ramus C1 via CNNXII
2. Sternohyoid = Depresses hyoid bone post swallow
Origin = Posterior SCJ
Insertion = body of hyoid
Anterior ramus C1-3 via ansa cervicalis
3. Omohyoid = depresses hyoid bone
Origin = superior scapula
inserts lower body of hyoid
Anterior rami C1-3 via ansa cervicalis
4. Sternothyroiud = draws larynx down
Origin = posterior surface of sternum
Insertion = thyroid cartilage
Anterior rami C1-3 via ansa cervicalis
193
Thyrocervical trunk - route and branches?
Arises medial to anterior scalene. Gives three branches:
1. Inferior thyroid = Ascends anterior to anterior scalene, then moves medial and posterior to carotid sheath
- The it moves medially it gives off ascending cervical and inferior laryngeal arteries
2. Transverse cervical artery = passes laterally and anterior to anterior scalene
3. Suprascapular - anterior to anterior scalene
194
What does internal thoracic artery branch off of, and what does it split into?
Branch of subclavian artery
As it passes 6th intercostal space it divides into superior epigastric and musculophrenic arteries.
