Head and Neck anatomy Flashcards
1
Q
Where is the foramen ovale found and what are its contents?
A
Found in the Sphenoid bone
OVALE
- Otic ganglion
- V3 division of trigeminal nerve (mandibular nerve)
- Accessory meningeal artery
- Lesser petrosal nerve
- Emissary veins
2
Q
What are the 6 foramen in the sphenoid bone?
A
- Foramen ovale
- Foramen spinosum
- Foramen rotundum
- Foramen lacerum
- Optic canal
- Superior orbital fissure
3
Q
What are the contents of foramen spinosum?
A
- Middle meningeal artery
- Meningeal branch of the mandibular nerve
4
Q
Through which foramen does the maxillary nerve (V2) transmit?
A
Foramen rotundum
5
Q
What foramen does the Internal carotid artery pass through?
A
First, travels through the carotid canal and then enters the skull through Foramen lacerum
6
Q
What 3 structures transmit through the optic canal?
A
- Optic nerve
- Ophthalmic artery (branch of ICA)
- Sympathetic nerves
7
Q
How does raised intra-cranial pressure affect the optic nerve?
A
The optic nerve is covered by 3 layers of dura.
Raised pressure in the dura will then also affect the optic nerve and cause papilloedema
8
Q
What will damage or occlusion of the ophthalmic artery cause clinically?
A
Sudden blindness
9
Q
What are structures that pass through the Superior orbital fissure?
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A
Live Free Sarah To See No Ignorant Ass Individuals
- Lacrimal branch of ophthalmic (V1)
- Frontal branch of ophthalmic (V1)
- Superior ophthalmic vein
- Trochlear (CN IV)
- Superior division of oculomotor nerve
- Nasociliary branch of ophthalmic (V1)
- Inferior division of oculomotor
- Abducens nerve )CN VI)
- Inferior ophthalmic vein
10
Q
In which part of the skull is the jugular foramen found?
A
Temporal bone
11
Q
Which foramen are located in the temporal bone?
A
- Jugular foramen
- Stylomastoid foramen
12
Q
What 2 structures transmit travel through the stylomastoid foramen?
A
- Stylomastoid artery
- Facial nerve
13
Q
What structures travel through the carotid canal?
A
SIDE
- Sympathetic plexus around arteries
- ICA
- Deep petrosal nerve
- Emissary veins
14
Q
What are the 12 cranial nerves?
A
1- Olfactory nerve
2- Optic nerve
3- Occulomotor nerve
4- Trochlear nerve
5- Trigeminal nerve
6- Abducens nerve
7- Facial nerve
8- Vestibulocochlear nerve
9- Glossopharyngeal nerve
10- Vagus nerve
11- Accessory nerve
12- Hypoglossal nerve
15
Q
What structures travel through the Jugular foramen?
A
Anterior: Inferior petrosal sinus
Intermediate: CN 9, 10, 11
Posterior: Sigmoid sinus, Internal Jugular vein
16
Q
Where is the foramen magnum found?
A
Occipital bone
17
Q
Which 3 vessels pass through the foramen magnum?
A
- Vertebral arteries
- Anterior spinal artery
- Posterior spinal artery
18
Q
Where is a patient likely to have a lesion if they have bitemporal hemianopia?
A
Optic chiasm
19
Q
In bitemporal hemianopia, how can the location of the optic chiasm lesion be distinguished?
A
Upper quadrant > lower quadrant = Inferior chiasma compression (pituitary tumour)
Lower quadrant > upper quadrant = Superior chiasma compression (craniopharyngioma)
20
Q
In patients with Homonymous quadrantanopia, how can a parietal vs temporal lesion be differentiated based on clinical findings?
A
PITS - lesions in the optic radiation
Parietal - Inferior quadrantanopia
Temporal - Superior quadrantanopia
21
Q
A patient has homonymous hemianopia with macular sparing. Where is the lesion?
A
Occipital cortex
22
Q
Where does the transverse sinus of the cranium drain into?
A
Drains into the sigmoid sinus
23
Q
What does the sigmoid sinus drain into?
A
Internal jugular vein
End of sigmoid sinus is the beginning of the Int Jugular vein
24
Q
Which 3 cranial sinuses converge and drain into the confluence of sinuses?
A
- Superior sagittal sinus
- Straight sinus
- Occipital sinus
25
Which sinus drains into the straight sinus?
Inferior sagittal sinus
26
Which sinuses drain into the sigmoid sinus?
- Superior petrosal vein
- Inferior petrosal vein
- Transverse sinus
27
How many paired and unpaired dural venous sinuses are there?
4 unpaired
6 paired (incl cavernous sinus)
28
What is the course of the cavernous sinus?
Paired. Found on the body of the sphenoid bone
Runs from the Superior orbital fissure to the Petrous temporal bone
29
What structures drain into the cavernous sinus?
- Superior ophthalmic vein
- Inferior ophthalmic vein
- Superior petrosal sinus
- Inferior petrosal sinus
- Basilar plexus of veins (posteriorly)
30
How can an infection of the face spread to brain?
If the infection spreads into the Superior and/or Inferior ophthalmic veins, the infection will spread, as these veins drain directly into the cavernous sinus
31
What are the contents of the cavernous sinus and what are its lateral wall components?
O TOM CAT
Lateral wall (from top to bottom)
- Oculomotor nerve (CN 3)
- Trochlear nerve (CN 4)
- Ophthalmic nerve (V1 of CN5)
- Maxillary nerve (V2 of CN5)
Contents (from medial to lateral):
- ICA (SN plexus)
- Abducens nerve (CN 6)
- Trochlear nerve (CN 4)
32
What is cavernous sinus syndrome usually caused by and what are clinical signs associated?
Most commonly caused by cavernous sinus tumours
Signs:
- Pain
- Ophthalmoplegia
- Proptosis
- Trigeminal nerve lesion
- Horner's syndrome
33
Which structure divides the anterior and posterior triangles of the neck?
SCM (sternocleidomastoid muscle)
34
What are the origins and insertions of the SCM?
Attaches at the clavicle and sternum and inserts into the mastoid
35
Which nerve innervates the SCM?
Accessory nerve
36
What are the borders of the posterior triangle of the neck?
Anterior: SCM
Posterior: Trapezius
Inferior: Middle 1/3 of clavicle
37
What muscles of the neck are found in the posterior triangle and make up its floor?
From superior to inferior
- Splenius capitis
- Levator scapulae muscle
- Posterior scalene
- Scalene medius muscle
- Anterior scalene muscle
38
What receives sensory information from the SCM?
Ansa cervicalis
39
What is the surface anatomy of the spinal part of the accessory nerve?
Located by drawing a line between the lower 2/3 of the trapezius muscle to the upper 1/3 of the SCM
40
How can the spinal part of the accessory nerve be damaged?
Surgery in the posterior neck (e.g. lymph node dissection)
41
If the accessory nerve is damaged in the posterior neck, which muscle is likely to be affected?
Trapezius muscle
At the point in which the accessory nerve is found in the post triangle, the SCM has already received its innervation and trapezius has not
42
What is the function of the scalene's anterior and medius?
Elevate 1st rib and laterally flex the neck to the same side
43
What is the function of Scalenus posterior?
Elevate 2nd rib and tilt neck to the ipsilateral side
44
What innervates the scalene muscles?
Spinal nerves C4-C6
45
What structures travels between the anterior and middle scalene muscles?
- Brachial plexus
- Subclavian artery
Go through a space called scalene hiatus
46
What is the relation of the subclavian vein and phrenic nerve to the anterior scalene muscle?
They pass anteriorly to it over the 1st rib
47
What is thoracic outlet syndrome and how is it caused?
Caused by compression of the brachial plexus and subclavian artery by the scalene muscles as they pass between scalene anterior and medius.
Patients will present with neuro-vascular symptoms in the upper limbs (e.g. cold extremities, numbness, weakness)
48
What are the boundaries of the anterior triangle of the neck?
Posterior: Anterior border of the SCM
Anterior: Midline of the neck
Superior: lower border of the mandible
49
What are the 3 sub triangles found in the anterior triangle of the neck and what do they contain?
- Submandibular triangle (digastric): contains Hypoglossal nerve + facial vessels + submandibular nodes and glands
- Muscular triangle: contains strap muscles and External Jugular vein + external carotid art.
- Carotid triangle: contains carotid sheath (common carotid / Vagus / Int jugular vein) AND Ansa cervicalis
50
How is the digastric muscle divided and what is its nerve supply?
Digastric has an anterior (inferior border of Digastric triangle) and posterior belly (border of carotid triangle).
Anterior: Mylohyoid nerve
Posterior: Facial nerve
51
Where is the external carotid artery found in the neck?
In the muscular triangle of the anterior triangle of the neck
52
What path does the hypoglossal nerve take to exit the carotid sheath?
Crosses over the ICA soon after the bifurcation of the common carotid (into ICA and ECA) and exits anterior to the ICA
53
What path does the glossopharyngeal nerve take to exit the carotid sheath?
Crosses over the ICA anteriorly and then exits the carotid sheath posterior to the ECA (as the ECA exits the sheath)
54
What nerves, vessels and muscles are found in the posterior triangle of the neck?
Nerves:
- Accessory nerve
- Phrenic nerve
- C2-C4 nerve roots (supraclavicular nerve / Transverse cervical nerve / Great auricular nerve / Lesser occipital nerve)
Vessels:
- Ext. jugular vein
- Subclavian artery (3rd part at the inferior border)
Muscles:
- Inferior belly of omohyoid
- all scalene muscles
55
What is the embryological origin of the parathyroid glands and how does this affect the position of the glands anatomically?
Derived from the 3rd and 4th pharyngeal pouches.
Parathyroids from the 4th pharyngeal pouch are located SUPERIORLY (associated with thyroid)
Parathyroids from the 3rd pharyngeal pouch are located INFERIORLY (associated with thymus)
56
If you are unable to locate the inferior glands of the parathyroid at its expected position, where else could they be located in view of their embryological origin?
Superior mediastinum
Inferior glands originate from the 3rd pharyngeal pouch which is associated with the thymus
57
What is the blood supply of the parathyroid glands?
Derived from the Inferior and Superior thyroid arteries (thyrocervical trunk and ECA respectively)
Rich anastomsis between the 2 vessels
58
What are the relations of the parathyroid?
Laterally: Common carotid
Medially: Recurrent laryngeal nerve AND Trachea
Anteriorly: Thyroid
Posterior: Pre-tracheal fascia
59
What structure connects the right and left lobes of the thyroid?
Isthmus
60
At what vertebral level is the superior thyroid notch found and what is the anatomical significance of this level?
Superior thyroid notch = C4
Level of bifurcation of the common carotid artery
61
What is the arterial supply of the thyroid and the origin of these vessels?
- Superior thyroid artery (1st branch of ECA)
- Inferior thyroid artery (thyrocervical trunk from subclavian artery)
- Thyroidea ima (10% of population from brachicephalic artery/aorta)
62
Where does the inferior thyroid vein drain into?
Brachiocephalic vein
63
Where do the superior and middle thyroid vein drain into?
Internal Jugular vein
64
What is the embryological origin of the thyroid?
Foramen caecum at the base of the tongue
65
What causes a thyroglossal cyst?
Incomplete closure of the foramen caecum
66
What does incomplete descent of the thyroid from the foramen caecum cause?
Pyramidal thyroid
67
What is the path of the salivary duct (stensen's duct) ?
Crosses the masseter, then pierces the buccinator and drains adjacent to the 2nd upper molar tooth
68
What are the 5 terminal branches of the facial nerve?
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- Temporal (raises eyebrows)
- Zygomatic (closes eyes)
- Buccal (blows cheeks out)
- Mandibular (allows for showing teeth)
- Cervical (tensing of the neck)
69
What structures pass through the parotid gland?
From superficial to deep
From superficial to deep:
- Facial nerve (all branches)
- Retromandibular vein
- Ext Carotid artery
- Auriculotemporal nerve (V3)
-LNs
70
What supplies the overlying skin of the parotid gland?
Great auricular nerve (C2-3)
Commonly damaged in parotid surgery
71
Which two veins of the face converge to form the Anterior facial vein?
- Supra-trochlear vein (from forehead)
- Supra-orbital vein (from forehead)
72
Which structures form the retromandibular vein and what is this vein also known as?
AKA Posterior facial vein
Formed by the unification of Superficial temporal vein AND Maxillary vein
73
What happens to the retromandibular vein after it enters the parotid gland?
It divides into its Anterior and Posterior divisions
74
What connects the Deep facial vein to the cavernous sinus?
Emissary veins
75
Which facial veins drain into the Internal jugular vein?
Anterior facial vein AND Anterior division of the retromandibular vein drain into the Common facial vein
Common facial vein drains into the Internal Jugular vein
76
What is the drainage site of the Posterior division of the retromandibular vein and Posterior auricular vein?
External Jugular vein
77
From which pharyngeal pouch does the Eustachian tube originate from?
1st pouch
78
What is the embryological origin of the palatine tonsils?
2nd pharyngeal pouch
79
What are nerve innervations of the parotid gland?
Parasympathetic: glossopharyngeal nerve (causes secretion of saliva)
Sympathetic: Superior cervical ganglion (causes flushing and sweating)
80
What effect on eating can damage to the nerve fibres in the parotid gland cause?
Frey syndrome
Causes sweating and flushing when eating as the sympathetic and parasympathetic innervations of the parotid gland are mixing post damage during surgery. This causes dual activation of fibres
81
Which cranial nerves carry parasympathetic fibres?
1973
CN3 - oculomotor fibres (pupillary constriction and accommodation through ciliary ganglion)
CN7 - facial nerve through Greater Petrosal Nerve (submandibular ganglion - lacrimal, sublingual, palatine)
CN9 - Glossopharyngeal (otic ganglion via Lesser Petrosal nerve and auriculotemporal nerve post-ganglionic for parotid)
CN10 - Vagus (heart and abdomen)
82
What are the superficial nerve relations of the submandibular gland?
Marginal mandibular nerve (branch of facial)
Cervical branch of facial nerve
83
Which nerves have an increased risk of damage during submandibular gland excisions?
- Marginal mandibular nerve (branch of facial)
(pt will lose ability to smile or show their teeth properly)
- Hypoglossal nerve
- Lingual nerve (wraps around the duct)
84
What are the deep nerve relations of the submandibular gland?
Hypoglossal nerve
Lingual nerve
85
Where does the submandibular duct open into the mouth?
At the frenulum of the tongue
86
What is the sympathetic and parasympathetic innervation of the submandibular gland?
Sympathetic: Superior cervical ganglion
Parasympathetic: via lingual nerve
87
What is the lymphatic drainage of the tip of the tongue?
Sub mental nodes
88
What is the lymphatic drainage site of the anterior 2/3 of the tongue?
Submandibular nodes and then to the ipsilateral deep cervical nodes
89
What is the motor innervation of the tongue?
Hypoglossal nerve (CN 12)
90
How can the hypoglossal nerve be tested?
Asking patient to stick their tongue out and moving it side to side
91
What provides taste and sensory innervation to the posterior 1/3 of the tongue?
Glossopharyngeal nerve
92
Which nerve provides taste sensation in the anterior 2/3 of the tongue and which nerve provides sensory innervation?
Taste: Facial nerve (via chord tympani)
Sensory: Mandibular nerve (V2) via lingual
93
What are the 3 structures that arise from the arch of the aorta?
- Brachiocephalic artery
- Left common carotid artery
- Left subclavian artery
94
What does the brachiocephalic artery/trunk divide into?
- Right common carotid artery
- Right subclavian artery
95
What is the course of the vagus nerves when branching off into the recurrent laryngeal nerves?
- Left vagus branches and loops under the arch of the aorta to begin ascending upwards as the LEFT recurrent laryngeal nerve
- Right vagus nerve branches and loops under the Right subclavian artery to begin ascending as the RIGHT recurrent laryngeal nerve
96
What 2 muscles does the subclavian artery travel between after its origin?
Between anterior and middle scalene muscles (deep to scalenus anterior)
97
What are the branches of the subclavian artery?
VIT C & D
VIT C & D
- Vertebral artery
- Internal thoracic artery (branches further into Inferior thyroid / Suprascapular / Transverse and Ascending cervical)
- Thyrocervical artery
- Costocervical trunk
- Dorsal scapular artery
98
Where does the common carotid artery terminate and divide?
Superior thyroid notch - C3/C4
99
What is the path of the internal carotid artery?
- Travels upwards after bifurcation and through the Carotid canal before entering the skull via Foramen Lacerum
- Travels vertically into the cavernous sinus where it runs transversely
- Travels vertically to exit cavernous sinus. Exits near the optic nerve where it gives off its first branch - Ophthalmic artery
- After branching, it travels transversely again before moving upwards and terminating at the circle of willis
100
Where are baroreceptors found in the carotid?
In the carotid sinus of the proximal ICA
101
Where are chemoreceptors found in the carotid and which nerve are they innervated by?
Found at the bifurcation of the common carotid
Supplied by Glossopharyngeal nerve (CN 9)
102
What are the branches of the External carotid artery?
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- Superior thyroid
- Ascending pharyngeal artery
- Lingual artery
- Facial
- Occipital
- Posterior auricular
- Maxillary artery (branches into middle meningeal artery / Inf alveolar artery)
- Superficial temporal artery
103
Where does the middle meningeal artery arise from?
Branch of maxillary artery
104
Which foramen does the middle meningeal artery pass through?
Foramen spinosum
105
Which bones form the Pterion?
- Parietal
- Frontal
- Squamous part of temporal
- Greater wing of sphenoid
106
What will the rupture of the middle meningeal artery cause?
Extra dural haematoma
107
Which cranial nerve is most susceptible to damage in raised intracranial pressures and why?
Abducens nerve (CN 6)
Due to have a very long intra-cranial course
108
What will damage to the trochlear nerve (CN4) lead to?
Inability to look down
109
Which nerve can be damaged during a carotid endarterectomy?
Hypoglossal nerve
due to its close relation to the carotid sheath
110
Which nerve is mainly responsible for the sensory supply of the face?
Trigeminal nerve (CN 5)
111
What are the 3 branches of the trigeminal nerve and where do they exit the skull?
Standing Room Only
- Ophthalmic nerve (V1)
- Maxillary nerve (V2)
- Mandibular nerve (V3)
Standing Room Only
V1: Superior orbital fissure
V2: foramen Rotundum
V3: foramen Ovale
112
Which branch of the trigeminal nerve provides sensory innervation to the tip of the nose?
V1 - Ophthalmic nerve
113
What is the sensory innervation of the angle of the jaw?
Greater auricular nerve (branch of cervical plexus C2-C3)
Rest of the face is supplied by Trigeminal nerve
114
Which branch of the trigeminal nerve carries sensory AND motor innervations and what do they supply via their motor aspect?
Mandibular nerve (V3)
Supplies motor function for muscles of mastication and some muscles of the neck:
- Masseter
- Temporalis
- Medial pterygoid
- Lateral pterygoid
-
115
Which nerve is susceptible to injury during parotid surgery or TMJ dislocation?
Auriculotemporal nerve (branch of mandibular nerve V3)
116
What does the facial nerve supply?
Face, Ear, Taste, Tear
Face: muscles of facial expression
Ear: nerve to stapedius
Taste: anterior 2/3 of tongue
Tear: parasympathetic fibres to lacrimal and salivary glands
117
What is the origin of the motor aspect of the facial nerve?
Pons
118
What is the course of the facial nerve to the face?
- Starts at the Pons as roots
- Passes through petrous Temporal bone into the internal auditory meatus with vestibulocochlear
- Then enters facial canal where the roots fuse to form facial nerve
- Then forms geniculate ganglion
- Exits cranium through Stylomastoid foramen
119
In a patient with cerebropontine tumour, which 2 nerves will be affected?
- facial nerve
- vestibulocochlear nerve
120
Where is the geniculate ganglion found and what nerve arises from here?
Found at medial aspect of the middle ear
Branch:
- Greater petrosal nerve (for lacrimal glands)
121
What is the course of the glossopharyngeal nerve in relation to the auriculotemporal nerve?
Glossopharyngeal nerve --> Inferior ganglion --> travels with Tympanic nerve --> Continue as Lesser petrosal nerve --> Otic ganglion where gives off parasympathetic fibres to Auriculotemporal nerve
122
If there is damage at the geniculate ganglion, what nerve function of the facial nerve will remain preserved?
Greater petrosal nerve (for Lacrimal gland)
this branches above the level of the geniculate ganglion and so is unaffected
123
What is the main difference in clinical presentation between an upper motor and lower motor neurone facial palsy?
Upper motor lesion: Upper part of face is spared. Only lower part of face affected (i.e. pt will still be able to raise their eyebrows)
Lower motor lesion: Entirety of face is affected + may also have loss of taste in anterior 2/3 of tongue, reduced lacrimation, hyperacusis
124
Which nerve provides sensation to the maxillary region of the face?
Infraorbital nerve, branch of maxillary nerve (V2 of trigeminal nerve)
125
What supplies sensation to the angle of the jaw and the skin overlying the parotid?
Great auricular nerve (C2-C3)
126
Where does the long buccal nerve arise from and what is its function?
Arises from mandibular nerve (V3)
Provides sensory innervation to the anterior cheek
127
Which nerve supplies the lower teeth and gums?
Mental nerve (branch of mandibular nerve V3)
128
Which muscles are innervated by the oculomotor nerve and what symptoms would arise in an Occulomotor nerve palsy?
Muscles:
- Superior rectus muscle
- Inferior rectus muscle
- Medial rectus muscle
- Inferior oblique
- Parasympathetic to sphincter pupillae
- Levator palpeerde superioris
3rd nerve palsy (3 Ds):
- Divergent eyes
- Dropping of eyelids (Ptosis)
- Dilated pupils (unopposed sympathetic activation of dilator pupillae)
129
The mandibular nerve supplies all muscles of mastication except one. Which muscle is this and which nerve is it innervated by?
Buccinators - supplied by buccal branch of facial nerve (CN7)
130
What does the inferior alveolar nerve supply and where does it arise from?
From mandibular nerve (V3)
Supplies:
- Sensory to lower teeth
- Sensory for lower cheek (as mental nerve)
131
Where does the vagus nerve arise and through which foramen does it exit the skull?
Arises from lateral surface of the medulla
Exits through Jugular foramen
132
When entering the mediastinum, what is the path of the left and right vagus nerves?
Left Vagus: lies in the interval between the common carotid and subclavian artery
Right Vagus: passes anterior to the 1st part of the subclavian artery
133
After beginning their ascent, what is the path of both recurrent laryngeal nerves?
- Pass in the groove between the trachea and oesophagus
- Enter the larynx behind the articulation of the thyroid cartilage and the cricoid
- distribute to the larynx muscles
134
Which muscle of the intrinsic larynx muscles is not supplied by the recurrent laryngeal nerve?
Cricothyroid muscle
135
Which nerve innervates the cricothyroid muscle and what is the function of this muscle?
External branch of the superior laryngeal nerve
Causes adduction of the vocal cords - responsible for high pitched voice
136
What are the effects of partial and complete injury to the recurrent laryngeal nerve in relation to the vocal cords and breathing?
Partial damage: affects breathing
Complete damage: affects voice only
Can both be bilateral or unilateral
137
What effects on breathing does partial unilateral and bilateral injury to the recurrent laryngeal nerve cause?
Unilateral partial: dyspnoea on exertion
Bilateral partial: Stridor
138
What affects on the voice does complete unilateral and bilateral injury to the recurrent laryngeal nerve cause?
Complete unilateral injury: hoarseness of voice
Complete bilateral injury: Aphonia (complete loss of voice)
139
Where is the Ansa Cervicalis found?
Anterior triangle of the neck
140
Which muscles of the neck does the Ansa cervicalis innervate?
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- GenioHyoid
- ThyroHyoid
- Superior Omohyoid
- SternoThyroid
- SternoHyoid
- Inferior omohyoid
141
What are the nerve roots of the Ansa cervicalis?
C1, 2, 3
142
Where should the inferior neck strap muscles be divided during surgery and why?
Divided in their upper half (i.e during a tracheostomy)
Nerve supply to the inferior strap muscles of the neck comes from the Ansa cervicalis and enters at their inferior aspect. Dividing these muscles in their upper half reduced risk of damage to this nerve supply
143
Which nerve supplies most of the external auditory meatus and lateral surface of the auricle?
Auricotemporal nerve (branch of mandibular V3)
144
What are the boundaries of the middle ear?
Lateral: Tympanic membrane
Roof: Tegmen tympani (can erode into the mastoid air cells by severe middle ear infection causing Mastoiditis)
Floor: Jugular wall - jugular vein runs under it
Medial: lateral wall of inner ear
145
What 2 nerves pass through the internal auditory meatus?
- Facial nerve
- Vestibulocochlear nerve
146
What effects does an acoustic neuroma have on the nerves passing through the internal auditory meatus?
Facial: damage to facial nerve can lead to paralysis of stapedius (nerve to stapedius) causing hyperacusis
Vestibulocochlear nerve: irreversible damage that can cause permanent hearing loss in the affected side
147
What is the blood supply of the lacrimal system?
Ophthalmic artery (from ICA)
drains via ophthalmic vein
148
What is the blood supply of the tonsils?
Tonsillar artery (branch of facial artery)
149
What structure is responsible for haemorrhage during tonsillectomy?
External palatine vein
Vein is immediately lateral to the tonsil and susceptible to injury
150
Which nerve is responsible for referred pain to the ear during episode of tonsillitis?
Glossopharyngeal nerve
151
Where is the site of a tracheostomy?
2nd to 5th tracheal rings
Midway between the cricoid and suprasternal notch
152
Where is the site of a cricothyroidotomy?
At the cricothyroid membrane located by a depression between cricoid and thyroid
153
What is the vertebral level of the angle of the mandible?
C2
154
What is the lymphatic drainage of the posterior 1/3 of the tongue?
Deep cervical nodes
155
What are the origins of the cranial nerves?
CN 9, 10, 11, 12 - from Medulla
CN 5, 6, 7, 8 - from Pons
CN 1, 2 - from anterior canal fossa
156
What is the rate of production of CSF and what is the total average volume of CSF in the system at any point?
20ml/hr
150ml total volume. CSF is recycled over 3x per day
157
What is path of CSF circulation?
--> Lateral ventricle
--> Foramen of Monro (interventicular foramen)
--> 3rd Ventricle
--> Cerebral aquaduct
--> 4th Ventricle
--> Foramen of Magendie (median aperature) / Foramen of Luschka (lateral aperture)
--> Subarachnoid space
--> Superior sagittal sinus
158
What key anatomical features are found at C6?
- Level of cricoid cartilage
- Site where carotid artery can be compressed against the transverse process of C6
- Junction of larynx and trachea (beginning of trachea)
- Joining of pharynx and oesophagus
- Recurrent laryngeal nerve enters larynx
- Inferior thyroid artery enters thyroid and middle thyroid leaves
159
How do spinal metastasis occur?
- Spread from primary tumour mainly by arterial route
- Retrograde spread Batson's venous plexus
- Direct invasion through intervertebral foramina
160
What are the 5 tumours that most commonly metastasise to the spine?
- Breast
- Lung
- Thyroid
- Kidney
- Prostate
161
What muscles are supplied by the ansa cervicalis?
GHost THought SOmeone Stupid Shot Irene
GenioHyoid
ThyroidHyoid
Superior Omohyoid
SternoThyroid
SternoHyoid
Inferior Omohyoid
162
What 3 arteries contribute to Littles area?
- Facial
- Maxillary (greater palatine artery)
- Ophthalmic (anterior ethmoidal artery)
163
Which artery lies between the submandibular gland and the mandible and is prone to damage during surgery?
Facial artery
164
A muscular defect in which two muscles causes a pharyngeal pouch?
- Thyropharyngeus
- Cricopharyngeus
165
What is the embryological origin of the recurrent laryngeal nerves?
6th pharyngeal arch
166
What is the blood supply of the 2nd pharyngeal arch?
Stapedial artery
Hyoid artery
167
Which pharyngeal arch do the muscles of mastication arise from?
1st pharyngeal arch
