Anatomy Flashcards
1
Q
What do the different parts of the ear do?
A
- External: collects soundwaves and directs them to middle ear
- Middle: conducts and amplifies vibration towards internal ear
- Internal: vibration/movement of fluid into action potentials
2
Q
What connects the middle ear to the nasopharynx?
A
Eustachian tube
3
Q
What is the basic anatomy of the nose?
A
- at the bottom is the hard then soft palate
- the nasopharynx is posterior to the nasal cavity
4
Q
What are the most important connections in the throat?
A
- Pharynx and oesophagus
- Larynx and trachea
!!tubular arrangement allows for movement of pathologies
5
Q
What is the arterial supply to the head and neck?
A
common carotids
subclavian
6
Q
What arteries supply the cranial cavity?
A
ICA vertebral artery (from SCA)
7
Q
What arteries supply the face?
A
ICA and ECA branches
8
Q
What arteries supply the neck?
A
ECA and SCA branches
9
Q
What are the branches off the external carotid artery?
A
from proximal to distal - superior thyroid artery - ascending pharyngeal artery - lingual artery - facial artery - occipital artery - posterior auricular artery - maxillary artery - superficial temporal artery (some anatomists like freaking out poor medical students)
10
Q
What is the venous drainage of the head and neck?
A
- follows arteries
- all drains to the internal jugular vein
!!danger triangle where veins can carry superficial infections to deeper head and neck areas
11
Q
What are the relevant cranial nerves for ENT?
A
1,5,7,8,9,10+12
12
Q
What are the features of the parasympathetic innervation to the head and neck?
A
- autonomic motor
- arise from CN7 and 9
- long then short neurones
- craniosacral outflow
13
Q
What are the most important parasympathetic ganglia in the head and neck?
A
CN7: submandibular and pterygopalatine
CN9: otic
14
Q
What is a ganglion?
A
collection of cell bodies in the peripheral nervous system
15
Q
What are the features of the sympathetic innervation of the head and neck?
A
- autonomic motor
- short then long neurones
- cervical sympathetic chain to peri-arterial plexus
16
Q
What are the features of the sensory innervation of the head and neck?
A
- three neurone chain
- synapses in the spinal cord and thalamus
- ganglion off the first neurone but no synapse
17
Q
What are the most important sensory ganglia of the head and neck?
A
trigeminal
geniculate
spiral and vestibular
18
Q
What are the features of the lymphatic drainage of the head and neck?
A
- follows veins
- most important groups of nodes are parotid, mastoid, deep cervical and superficial cervical
19
Q
What are the structures for turbulence in the nasal cavity?
A
superior, middle and inferior conchae
20
Q
What are the foramina in the nasal cavity?
A
- anterior ethmoidal (superior)
- posterior ethmoidal (superior)
- incisive (in midline)
- sphenopalatine (posterior-ish)
21
Q
What are the parts of the nasal septum?
A
- septal cartilage
- vomer
- perpendicular plate of the ethmoid
22
Q
What are the five contributors to Kiesellbach’s plexus (Little’s area)?
A
Ophthalmic artery= (from ICA)
- posterior ethmoidal
- anterior ethmoidal
Maxillary artery= (from ECA)
- sphenopalatine
- greater palatine (branch of above)
Facial artery= (from ECA)
- septal branch of superior labial artery (branch of lateral nasal)
23
Q
What are the internal parts of the nose and their epithelium type?
A
- nasal septum (around superior concha): olfactory epithelium, create turbulence, air reaches receptors
- nasal septum (around middle and inferior conchae): respiratory epithelium
- nasal vestibule: stratifies squamous epithelium with keratinised on outside skin and non-keratinised on inside
24
Q
What is the setup in the superior nasal cavity?
A
there are bipolar nerves going through from olfactory bulb (like a toothbrush) and the olfactory tract (toothbrush handle) takes the signals back to the brain
25
What is the somatic sensation to the nasal cavity?
- anterior and superior is V1= anterior ethmoidal nerve
| - posterior and inferior is V2= nasopalatine nerve
26
What is the trigeminal ganglion?
a mixture of all of the ophthalmic, maxillary and mandibular division of this nerve converging in one place
27
What are the parts of the external ear?
- tragus
- anti-tragus
- helix
- anti-helix
- lobe
- concha
28
What is the innervation to the tympanic membrane?
vagus and CNV3 nerve
29
What are the names for the outer ear?
pinna
| auricle
30
What are the three ossicles called?
(from lateral to medial) the malleus, incus and stapes
31
What joins the ossicles?
synovial joints join these bones to reduce the chance of breaking and to reduce friction
32
Where does the stapes sit?
in the oval window (the round window is below)
33
What are the skeletal muscles of the ear and their functions?
- stapedius: attaches to the stapes, it dampens sound by reducing vibrations (eg shouting and this works with muscles of opening the mouth and mastication)
- tensor tympani: also dampens sound by reducing vibrations of the tympanic membrane
34
How is air pressure in the ear changed?
by the Eustachian tube which is operated by the palate muscles
35
What happens when the outside pressure is greater than inside the tympanic cavity?
tympanic membrane pushes in which can be corrected by doing the valsalva maneuver
36
What happens when the outside pressure is lesser than inside the tympanic cavity?
tympanic membrane pushes out which can be corrected by yawning or opening mouth wide
37
What can happen when the tympanic membrane is pushed in or out?
reduced vibration of ossicles when the membrane is either in or out and this increases potential for barotrauma
38
How do infections spread to ear and nose?
Eustachian tube connects the anterior wall of the middle ear to the nasopharynx so can be the cause of infections spreading around
39
Why do children get more spread of infections in the ear?
- distance to ear is shorter in children from nasopharynx to middle ear so more likely to have infections spread
- tonsils/immune system are not fully developed
40
Why can ear pain be from facial pain and vice versa?
a common sensory nerve supply here so tonsillitis or pharyngitis can mimic earache
41
What supplies the general sensation of the tympanic cavity mucosa?
Tympanic plexus is on the promontory which is CNIX (through jugular foramen)
42
How does mastoiditis occur?
- epitympanic cavity is the superior part of the tympanic cavity (this is where the mastoid aditus lies)
- an infection can enter the mastoid process and the mastoid air cells which can cause osteomyelitis
- (can also be used as surgical access to the tympanic cavity )
43
What is in the Otic capsule?
(fully formed at birth)
- bony labyrinth (filled with perilymph)
- membranous labyrinth which is suspended in the bony labyrinth (filled with endolymph)
44
How does hearing occur from the bony labyrinth?
- vibrations make the tympanic membrane vibrate which passes through the ossicles, this then rocks the stapes into the oval window
- waves of fluid in the perilymph which goes all the way through the cochlea moving hair cells and creating APs
- goes around and hits the round window which absorbs the vibration and dissipates the forces in the air filled cavity
- APs made are conveyed to the brain by the cochlear nerve
45
How does hearing occur in the membranous labyrinth?
- membranous labyrinth filled with endolymph is stimulated by the vibrations outside and then
- the hair cells move around the organ of Corti and APs are made
- cochlear duct divides the cochlear canal into the scala vestibuli and the scala tympani
46
Where is the issue in a conduction or sensorineural hearing problem?
- conductive (external or middle ear)
- sensorineural (inner ear) hearing loss
Weber test and Rhine test
47
Where are the different frequencies of waves picked up?
high frequency close to the oval window
| low frequency far away from oval window
48
What is responsible for balance and head movement?
- vestibular apparatus
- saccule and utricle
- semicircular ducts
49
What detects linear horizontal and vertical movement?
- horizontal: utricle
| - vertical: saccule
50
What detects angular sagittal, coronal and axial movement?
- sagittal: anterior semicircular canal
- coronal: lateral semicircular canal
- axial: posterior semicircular canal
51
How is balance detected?
- head moves so cupula with hair cells moves
- endolymph fluid stays still until it builds momentum
- fluid opens ion channels causing depolarisation
52
What is the nerve supply to the inner ear?
- vestibular nerve from the vestibular apparatus
- cochlear nerve from the cochlea
- join together to form CNVIII which is the vestibulocochlear nerve which goes to the pontomedullary junction
53
What goes through the internal acoustic meatus?
- CN7 facial nerve
- CN8 vestibulocochlear nerve
- labyrinthine artery
54
What are the facial nerves functions and what goes wrong if these aren't working?
- Parasympathetic: dry eye, dry mouth and dry mucosa
- Special sensation: lack of taste anterior 2/3rd of tongue
- Somatic motor: facial paralysis
- General sensory
55
What are the portions of the facial nerve?
- Cranial: cerebellopontine angle and enters internal acoustic meatus
- Temporal: nerve to stapedius, greater petrosal nerve (eye, nasopharynx and palate)
- Extratemporal: chorda tympani runs in between the malleus and the incus and joins the lingual nerve and there is a submandibular ganglion
56
What are the names of the papillae?
Foliate papillae
Vallate papillae
Fungiform papillae
Filiform papillae (no tastebuds)
57
What is the pterygopalatine ganglion associated with?
the parasympathetic secretomotor supply of the facial nerve
58
What joins together to make to vidian nerve?
- greater petrosal nerve: from geniculate ganglion to pterygopalatine ganglion
- deep petrosal nerve
59
What does each nerve bring to the vidian nerve?
- greater petrosal brings preganglionic parasympathetic axons and it then synapses in the pterygopalatine ganglion
- deep petrosal nerve brings postsynaptic sympathetics which don't synapse in the pterygopalatine ganglion
60
What suspends the vidian nerve?
inputs from the maxillary nerve
61
What other branches join the pterygopalatine ganglion?
branches from CNV1 from lacrimal gland which join to CNV2 by zygomatic nerve
62
What does disruption at the vidian nerve cause?
- dry nasal cavity
- dry nasopharynx
- ipsilateral dry eye
63
What does disruption at the internal acoustic meatus cause?
- dry nasal cavity
- dry nasopharynx
- ipsilateral dry eye
- no taste in anterior 2/3rds of tongue
- facial paralysis
64
What are the three phases of swallowing?
oral, pharyngeal and oesophageal phases
65
What is involved in the oral phase of swallowing?
voluntary, mastication and bolus manipulation
66
What do the muscles of mastication do in swallowing?
Muscles of mastication (CNV3) break down the food and allow it to mix with saliva
67
What do the facial muscles do in swallowing?
labial seal (orbicularis oris) and cheek tightening/pushing the food back to the back teeth (buccinator)
68
What do the tongue muscles do in swallowing?
(CNXII) manipulate the bolus and align it between the teeth
69
What does the soft palate do in swallowing?
Soft palate (CNX) depresses to create an oropharyngeal seal and the tongue ripples the bolus backwards
70
What is the hard palate made of and supplied by?
- keratinised stratified squamous epithelium to protect against abrasions
- palatal rugae
- supplied by branches of pterygopalatine ganglion so secretomotor is CNVII and general sensation is CNV2
71
What are the features of CNXII?
- hypoglossal nerve which runs in the hypoglossal canal which is at 10 and 2 from foramen magnum
- supplies all the muscles of the tongue except the palatoglossus
72
What is the course of CNXII?
its course is from medulla, through hypoglossal canal, descends close to carotid sheath, lateral to hyoglossus into floor of mouth
73
What is involved in the pharyngeal phase of swallowing?
- hyolaryngeal elevation, sequential constrictor contraction
- very short phase- less than a second unless there is pathology
74
What are the stages of the pharyngeal phase of swallowing?
- Elevation of the soft palate and seals nasopharynx
- The hyoid bone is dragged superiorly and anteriorly by the suprahyoid and the longitudinal pharyngeal muscles
- epiglottis inferior to the tongue to the tongue and covers the laryngeal aditus to protect the airway
- Bolus into oesophagus by tongue pressure, contraction of constrictors and relaxation of upper oesophageal sphincter (cricopharyngeus)
75
What is involved in the oesophageal phase of swallowing?
peristalsis, relaxation of upper oesophageal sphincter, involuntary phase
76
What is the cricopharyngeus?
- complete circular ring around the cricoid cartilage
| - quite thick and is innervated by external laryngeal nerve which is a branch of the CNX
77
Where is the parapharyngeal space?
runs parallel to the outside of the pharynx
78
Where is the retropharyngeal space?
- behind the pharynx and can spread infection to the mediastinum
- danger space is next to the alar fascia which has potential to travel from head down to mediastinum
79
What does the pharyngeal plexus do?
- innervates the soft palate and the pharynx muscles except the tensor veli palatini
- formed by CNIX and CNX
80
What is the sensory part of the gag reflex?
stimuli to posterior ⅓ of tongue, palatine tonsils and wall of oropharynx which are all innervated by CNIX (afferent = CNIX)
81
What is the motor component of the gag reflex?
tries to close off the oropharynx involving constrictors of the pharynx (CNX), longitudinal muscles of pharynx (CNIX and CNX) and tongue (CNXII) and soft palate (CNX) (efferent = CNIX, CNX, CNXII)
82
Where is the gateway to the mouth?
- gap between the superior and inferior pharyngeal constrictor muscles
- here is the Glossopharyngeal nerve, the lingual artery and the stylopharyngeus muscle
83
What are the tonsils that are removed and what can be a complication?
- Palatine tonsils
| - glossopharyngeal nerve can be hurt and this will lose some gag and posterior 1/3rd taste
84
What does the posterior cricoarytenoid do?
lateral rotation at cricoarytenoid joint which widens the rima glottidis (forced respiration)
85
What does the lateral cricoarytenoid do?
closes the rima glottidis with the arytenoid muscle doing the final close
86
What are the components of phonation?
inspiration, controlled expiration and then phonation itself
87
What is involved in the controlled expiration phase of phonation?
- contraction inspiratory muscles
- builds pressure in respiratory tree below the larynx
- pressure depends on task
88
What is involved in the phonation phase of phonation?
- adduction of vocal cords and the expiratory muscles increase subglottic pressure
- this pushes through and vocal folds ripple which creates air vibration
89
What are the movements of the vocal cords and their result?
- Tension increases pitch
- Relaxation decreases pitch
- Adduction quietens
- Abduction loudens
90
What are the intrinsic muscles of the larynx supplied by?
skeletal and innervated by inferior laryngeal branch of CNX (except the cricothyroid which is external laryngeal nerve)
91
What do the arytenoids and the lateral cricoarytenoids do?
- arytenoids- phonation
| - lateral cricoarytenoids- whispering
92
What does the thyroarytenoid do?
relaxes the vocal ligament and decreases pitch
93
What does the cricothyroid muscle do?
muscle tenses the vocal ligament
| this increases pitch
94
What is the mucosal innervation to above and below the vocal folds?
Mucosa above the vocal folds is the internal laryngeal nerve
Mucosa below the vocal folds is inferior laryngeal nerve
95
What is the path of the vagus nerve in this area?
- through jugular foramen
- gives off superior laryngeal nerve
- runs down in carotid sheath
- gives off recurrent laryngeal nerve which hooks under the aorta and then becomes the inferior laryngeal nerve
96
What are the parts of cough?
- Glottic closure by lateral cricoarytenoid and arytenoid
- Muscles contract to increase body cavity pressure
- Glottic release of high pressure air jet
97
What does the vagus supply in ENT?
sensory and motor supply to palate, pharynx and larynx
98
How can the action of the vagus nerve be tested I the larynx and pharynx?
- Pharynx: ask patient to swallow sip of water and larynx will move up and down
- Larynx: ask patient to speak and the intrinsic laryngeal muscles are functioning normally to move vocal cords
99
What is dysphonia?
inability to produce an appropriate level of phonation
100
Where does a supraglottic tumour spread to?
drain to superior deep cervical nodes
101
Where does a subglottic tumour spread to?
to paratracheal nodes and present with voice/airway obstruction
102
What happens to glottic tumours?
usually stay in the nodes and present with voice changes/airway obstruction
103
What are the features of vocal nodules?
lumps on rima glottidis and cause pain when speaking
104
What is the cause of unilateral vocal cord palsy?
recurrent laryngeal nerve is cut
105
What happens in the resonance of speech?
larynx makes sound and the buzz is amplified by the pharynx, oral and nasal cavities
106
What happens in the articulation of speech?
oral sounds come from soft palate tensing (CNV3) and elevating (CNX)to close off nasopharynx
nasal sounds come from soft palate tensing and descending to close off oropharynx
107
What are the main cranial nerves for referred pain to the ear?
- CNV2+3- trigeminal (facial sensation and mastication)
- CNVII- facial (facial expression, taste ant. 2/3rd, salivary and lacrimal glands)
- CNIX- glossopharyngeal (parotids, taste post. 2/3rd, palatine tonsils and gag)
- CNX- vagus (sensory and motor)
108
What supplies the tympanic membrane?
```
internal = glossopharyngeal nerve
external = split with a bit of vagus at the inferior side, the rest is CNV3
```
109
What are the main causes of ear pain if the ear is normal?
- Teeth
- Tongue
- TMJ
- Throat
- Trigeminal neuralgia
110
What are the sinuses of the face?
frontal
ethmoid air cells
sphenoidal
maxillary
111
What are the exit places of the CNs from the brain?
- Cribriform plate = CNI
- Optic canal = CNII
- Superior orbital fissure CNIII, CNIV, CNV1, CNV
- Foramen rotundum = CNV2
- Foramen ovale = CNV3
- Internal acoustic meatus = CNVII, CNVIII
- Jugular foramen = CNIX, CNX
- Hypoglossal canal = CNXII
112
What node drains the palatine tonsils?
Jugulo-digastric node
113
What is the best scan for the sinuses?
CT scan
114
What nerve runs through the posterior triangle?
the accessory nerve
115
What does the 6th cranial nerve run through?
the cavernous sinus
116
What nerve runs superficial to the submandibular gland?
the marginal mandibular nerve
117
Which nerve runs near the lower wisdom teeth?
inferior alveolar nerve
