Applied Head, Neck, Neuroanatomy. Flashcards
(383 cards)
1
Q
What are the 3 layers of the deep cervical fascia from superficial to deep?
A
From superficial to deep
- Investing layer
- Carotid sheath
- Pre tracheal layer
- Pre vertebral layer
2
Q
Which structures are enclosed by the investing layer?
A
Sternocleidomastoid
Trapezius
Submandibular
Parotid salivary glands?
3
Q
What are the complications of an infection that develops in the retropharyngeal space?
A
Can potentially spread from the neck into the thorax as far down as the posterior mediastinum risking development of a mediastinitis
4
Q
Where does the retropharyngeal space lie?
A
Between the Pre-vertebral layer of fascia and the fascia surrounding the pharynx.
5
Q
Impingement of which nerve leads to loss of mastication?
A
Cranial Nerve 5 - Trigeminal nerve
Mandibular division supplies the muscles of mastication
6
Q
Impingement or damage of which nerve leads to loss of facial expression?
A
Facial nerve
7
Q
What is Bell’s palsy?
A
Inflammation of the facial nerve. Inflammation causes oedema and compression of the facial nerve as it runs through the internal acoustic meatus in the petrous part of the temporal bone
8
Q
What can be used to examine the sternocleidomastoid?
A
Put hand on the patients neck and ask them to look over their shoulder
(Lateral flexion of head is by the action of sternocleidomastoid)
9
Q
What can be used to test the accessory nerve?
A
Shrug against resistance to test damage to nerve that supplies the trapezius
10
Q
What are the borders of the anterior triangle?
A
Superiorly: inferior border of the mandible
Laterally: Medial border of the sternocleidomastoid
Medially: Imaginary saggital line down the midline of the body
11
Q
What are the borders of the posterior triangle?
A
Anterior: Posterior border of the sternocleidomastoid
Posterior: Anterior border of the trapezius muscle.
Inferior: Middle 1/3 of the clavicle.
12
Q
What does inserting surgical airways carry the risk of?
A
Infection of the pre tracheal space
13
Q
What are the 3 branches of the trigeminal nerve?
A
- Opthalmic division
- Maxillary division
- Mandibular division
14
Q
Loss of sensation in the scalp correlates with which nerve?
A
Trigeminal nerve
Provides main sensory innervation to scalp and face
15
Q
What is the main arterial supply of the head and neck?
A
-Common carotid artery which is the main arterial supply via its terminal branches
16
Q
What are the main venous drainage from the face, head and neck?
A
- Internal jugular vein which is the main venous drainage of head and neck structures.
- External jugular vein which also receives veins draining the scalp and face and runs more superficially than the IJV
17
Q
What are the branches of the common carotid artery?
A
- Internal carotid artery
- External carotid artery (facial artery branch supplies the face)
18
Q
Why is swallowing, movement of thence typically difficult and painful for a patient with a retropharyngeal abscess?
A
Compression of oesophagus causes pain to be elicited when moving the neck or swallowing
19
Q
What are the extra-cranial branches of the facial nerve?
A
Superior to inferior
- Temporal (above the eyes at side of head)
- Zygomatic (nose region)
- Buccal (mouth region above the lip)
- Mandibular (mouth region below lip)
- Cervical (neck region)
20
Q
How can the trigeminal nerve be tested?
A
- Movement of the jaw
- Sensory of the face
21
Q
How can the facial nerve be tested?
A
- Smile
- Frown
- Closing eyes
- Raising eyebrows
22
Q
How can the orbicularis be tested?
A
-CLose the eyes tightly and resist me trying to open them
23
Q
How can the levator palpebrae superioris be tested?
A
Elevation of the upper eyelid
24
Q
What nerve damage results in loss of elevation of the eyelid?
A
Oculomotor nerve
25
What is the examination for for occipitofrontalis muscle?
Raise the eyebrow against resistance
26
What is the examination for the orbicularis oris?
Purse lips and try to pull it up
27
What is the examination for the buccinator?
Blow out cheeks and resist expulsion of air
28
What is the action of the Buccinator?
- Keeps food from spilling into the cheek.
- Flattens cheek and holds the cheek close to the teeth when chewing.
- Prevents food pooling between cheek and gums
29
Which muscles are innervated by the mandibular branch of the trigeminal nerve?
- Medial pterygoid
- Masseter
- Temporalis
- Lateral pterygoid
30
What is the examination for the temporalis?
Palpation during jaw clench
31
What layers would the scalpel penetrate before it reached the bone?
- Skin
- Dense Connective tissue
- Epicranial aponeurosis
- Loose areolar connective tissue
- Periosteum
32
How is spread of bleeding within the subperiosteal layer limited?
There are membranous gaps in the sutures which the blood goes into which limits the spread of bleeding within the sub-periosteal layer.
33
Which suture can be found between the parietal bones?
Sagittal Suture
34
Which suture can be found between the frontal bone and parietal bones?
Coronal Suture
35
What suture can be found between the occipital bone and parietal bone?
Lambdoid suture
36
What are the 3 bowl shaped depression formed on the cranial floor?
- Anterior Cranial Fossae
- Middle Cranial Fossae
- Posterior Cranial Fossae
37
What is the trilaminar arrangement of the calvaria?
```
Outer Table (compact bone)
Diploeic Cavity (spongy bone)
Inner table (compact bone)
```
38
When does growth at sutures stop?
Puberty
39
Why are the edges of the bones of the skull serrated?
To prevent slippage and movement
40
Periosteum covering the outer table is continuous through to the periosteum covering the inner table. True/False
True
41
Where does a cephalohaematoma occur?
Occurs between the periosteum and outer table of bone
42
Can bleeding in a cephalohaematoma pass the suture lines?
It cannot cross the suture lines
43
What are the purposes of fontanelles?
- To allow for altering of the skull size and shape during child birth
- To permit growth of infant brain
44
When do the fontanelles fuse?
Posterior - 1 month to 3 months
| Anterior - 18 months to 2 years
45
What is early fusion of fontanelles and sutures called?
Craniosyntosis
46
What is the shape of the fontanelles?
Slightly convex shape in a healthy baby
47
What should be performed in all partients with known or suspected skull fractures?
CT scanning should be performed to identify intra cranial injuries
48
Why is the pterion particularly at risk of fracture?
It is the thinnest area of the skull. Fusion between parietal, temporal, frontal and sphenoid
49
What are the two main types of fractures?
Linear - pass full thickness of skull. It is failed strains and involve no bone displacement
Depressed - Fragment is displaced inwards towards the brain
50
What are basilar skull fractures and what are their risks and signs?
Fractures involving the cranial base
Risks
- Associated with cranial nerve injuries
- Prone to causing cerebrospinal fluid leaks
Signs
- Raccoon eyes
- Battle signs
- Haemotympanum
51
What is the risk with the pterion?
Intracranial Haemorrhage due to the injury to the middle meningeal artery. Extradural haematoma
52
What the 3 sacs around the brain and their properties?
Dura: tough fibrous membrane
Arachnoid: soft translucent membrane
Pia: microscopically thin, delicate and closely adherent to surface of brain
53
What are the layers of the dura?
```
Periosteal = endosteum lining the inner bones of skull
Meningeal = Layers adjacent to arachnoid
```
54
What is the purpose of the dural folds?
Helps to stabilise the brain and act as Rigid dividers
55
What can a rise in pressure inside the skull lead to?
Compression and displacement of the brain against the rigid folds and/or through foramen magnum. (herniation)
56
What are the effect of a rise in pressure on the cranial nerves?
Their roots have a close relationship with the dural folds so they can get squashed
57
What are dural venous sinuses?
Venous blood filled spaces created by separation of meningeal from periosteal layer of the dura.
58
Where does venous blood from the brain drain to?
Venous sinuses via the cerebral veins
59
Where is the confluence of sinuses found?
Deep to the protuberance of the occipital bone
60
How do cerebral veins within the subarachnoid space drain into the dural venous sinuses?
Bridging veins
61
What is a common cause of extradural haemorrhage and where does it occur?
Arterial bleed via the middle meningeal artery.
Bleeding occurs between the inner table of bone and periosteal
62
What is a common cause of subdural haemorrhage?
Venous bleed through the bridging veins.
63
What is subdural haemorrhage?
-Bleeding between the meningeal layer of the dura and the arachnoid mata.
64
Why doesn't the bleed frimm a subdural haemorrhage spread across the brain?
Falx cerebri (dural folds) stops the spread across the side of the brain
65
Why are older people more susceptible to subdural haemorrhage?
- The Brian gets smaller as you get older
- Increase tension of the bridging veins
- A slight knock could cause the veins to rupture as a result
66
What usually cause a subarachnoid haemorrhage?
-Usually a branch of the circle of willis
Secondary to trauma or spontansous rupture of the blood vessel
67
What is the path of the vetebral arteries?
- Arise from the subclavian arteries on the right and left
- Ascend in the neck through transverse foramina in cervical vertebrae 6-1 and pass through the foramen magnum
- Form the basilar artery
68
Where does the internal jugular vein lie?
Lateral to the common carotid and mostly under the sternocleidomastoid
69
Where does the common carotid artery bifurcate?
-C4 at the level of the superior border of the thyroid cartilage
70
What commonly forms at the birfurcation of the carotid artery and what is the effect?
Atheromas. This causes stenosis of the artery. Also rupture of the clot can cause an embolus to travel to the brain. Leading to a transient ischameic attack
71
Why is the swelling more bulbous at the region of the bifurcation?
Carotid Sinus at the region of the bifurcation
Baroreceptors for detecting changes in arterial blood pressure.
72
What is located in the carotid body?
Peripheral chemoreceptors which detect arterial O2.
73
What are the borders of the carotid triangle?
Superior: Posterior belly of the digastric muscle.
Lateral: Medial border of the sternocleidomastoid muscle.
Inferior: Superior belly of the omohyoid muscle.
74
What is the importance of the carotid triangle?
- Important for surgical approach to the carotid arteries or internal jugular vein
- Access the vagus and hypoglossal nerves
- Carotid pulse can felt in just below the birfurcation
- Carotid sinus massage
75
How can you terminates a supraventricular tachycardia at the carotid sinus?
- A carotid massage increase pressure in the artery
- This means that the glossopharyngeal nerve is stimulated and send signal to the brain.
- The efferent signal to slow the heart down from the brain is transmitted by the vagus nerve
76
What are the contents of the cavernous sinus?
- Plexus of extremely thin-walled veins on upper surface of sphenoid
- Internal carotid artery
- Oculomotor nerve
- Trochlear nerve
- Abducent nerve
- Opthalmic and Maxillary nerve of the trigeminal nerve
77
What is the blood supply to the scalp and their roots?
From internal carotid artery
- Supra-orbital artery
- Supratrochlear artery
From external carotid artery
- Superficial temporal artery
- Posterior auricular artery
- Occipital artery
78
Where do the blood vessels in scalp lie?
In subcutaneous connective tissue layer
79
How is constriction of the blood vessels limited in dense connective tissue layer and what are the issues of this?
- Walls of the arteries are closely attached to dense connective tissue.
- You can get profuse bleeding as a result of an open scalp wound
80
The Loss of the scalp results in bone necrosis. True/False
False. Blood supply to the skull is mostly via the middle meningeal artery
81
Where can the facial artery pulse be felt?
- Inferior border of mandible
| - Anterior to the masseter muscle
82
What is the clinical relevance of the Kiesselbach area?
Common site of nose bleeds.
83
What are the most important branches of the kiesselbach area?
- Septal branch of sphenopalatine artery
| - Anterior ethmoidal arteries
84
What are the shapes of the extradural and subdural haemorrhage?
- Extradural: Pear
| - Subdural: Banana shape. Slim
85
What is the venous drainage of the scalp?
- Superficial temporal veins
- Occipital vein
- Posterior auricular veins
86
What is the connection between the venous drainage of the scalp and dural venous sinuses?
Several emissary veins connect the veins of the scalp then to the dural venous sinuses. Can act as a potential route for infection to spread.
87
What is the effect of the spread of infection from the scalp to the cranial cavity?
It can affect the Meninges
88
What is special about emissary veins and the veins of the face?
They are valveless
89
What are the contents of the cavernous sinus?
- Internal carotid artery
- Oculomotor nerve
- Trochlear nerve
- Abducent nerve
- Opthalmic and maxillary branch of the trigeminal nerve
90
Which is a better indicator of the pressure of the right atrium? IJV or EJV
Internal Jugular Vein is better indication pressure in the right atrium
91
How do you measure the jugular venous pressure?
- Use the right Internal jugular vein
- PAtient at a 45 degree angle with the head slightly to the left
- Pulsations are observed through the sternocleidomastoid muscle which hide the internal jugular vein
- The height measured in 5cm from the sternal angle
- MEasured in cmH2O
92
What are some important branches of the maxillary artery?
- Middle meningeal
| - Sphenopalatine
93
What is the function lymphatic vessels?
- Continuous removal of remaining tissue fluid and proteins from extracellular space back to blood circulation.
- It is also a route for spread of infection and malignant disease
94
What is uni-directional flow of lymph?
- Tissue fluid
- Lymphatic Capillary
- Lymphatic vessels
- Lymph nodes
- Lymphatic vessels
- Lymphatic trunks
- Lymphatic ducts
- Venous system
95
How does the fluid flow thorough the lymphatic systems?
- Passive constriction
- Intrinsic constriction
- Fluid goes through valves
96
What are the causes of lymphoedema?
- Removal or enlargement of lymph nodes
- Infections
- Damage to lymphatic system such as cancer treatments
- Lack of limb movement
- Congenital issues (such as Milroy's syndrome)
97
What is the key role of the lymph nodes?
-Immune surveillance and defence
98
How does the lymph node achieve its roles?
Highly organised centres of immune cells such as lymphocytes and macrophages. This helps it deal with the pathogens if they are present in the lymph fluid due to transfer from an infected tissue
99
What the common causes of an enlarged lymph node?
- Infection
| - Malignancy
100
What does an enlarged lymph node as a result of infection feel like?
- Tender
| - Mobile
101
What does an enlarged lymph node as a result of malignancy feel like?
- Hard
- Matted
- Non-tender
102
Where are specific regions in the body where lymph nodes are palpable?
- Neck (cervical)
- Armpit (axillary)
- Diaphragm
- Spleen
- Abdominal
- Pelvic
- Groin
103
What separates the deep and superficial lymph nodes in the neck?
Terminal node lie deep to Investing layer of deep cervical fascia
104
Where are lymph nodes located?
- Submental
- Sub-mandibular
- Pre-auricular
- Post auricular
- Occipital
105
What is waldeyer's ring?
Annular collection of lymphatic tissue surrounding the entrance to the aerodigestive tracts
106
What are the tonsils that form Waldeyer's ring?
- Pharyngeal tonsil
- Tubal tonsil
- Palatine tonsils
- Lingual tonsils
107
Where do lymphatics from tonsils draining the upper pharynx drain into?
Retropharyngeal Lymph Nodes
108
What forms the myelin sheath in the CNS and PNS?
- Oligodendrocyte in the CNS
| - Schwaan cells in the PNS
109
What does the midbrain do?
- Eye movements
| - Reflex responses to sound and vision
110
What does the pons of the brain control?
- Feeding
| - Sleep
111
What does the medulla of the brain control?
- Cardiovascular and respiratory centres of the brain
| - Contains a major motor pathway called the medullary pyramids
112
How is the body controlled by the brain?
Contralateral side of the brain control the body
Left side of the cortex control the right side of the body
113
What is an important sulcus and what are the structures lieing anterior and posterior to it?
Central sulcus
- Precentral gyrus - control of motor function
- Post central gyrus - control somatosensory functions
114
What is the purpose of the frontal lobe?
- Higher cognition
- Motor function
- Speech
115
What is the purpose of the parietal lobe?
- Sensation
| - Spatial awareness
116
What is the purpose of the temporal lobe?
- Memory
- Smell
- Hearing
117
What is the purpose of the occipital lobe?
Vision
118
What is the clinical significance of the uncus?
-Part of the temporal lobe that can herniate compressing the midbrain
119
What are the medullary pyramids?
-Location of descending motor fibres
120
What is the corpus callosum?
-Fibres connecting the two cerebral hemispheres
121
What is the function of the thalamus?
-Sensory relay station projecting to sensory cortex
122
What is the function of the hypothalamus?
-Essential centre for homeostasis
123
Where is the common site of atherosclerosis in the common carotid artery?
Near the bifurcation of the arteries into the external and internal carotid artery
124
How can an atheleorscelrotic plaque in the internal carotid artery cause transient vision loss?
Ophthalmic artery is given of the internal carotid artery which result in vision loss due to lack of blood supply
125
What do the ventricles in the brain appear as in a CT scan?
-Appears black
126
Damage to the right cerebellum results in what on which side of the body?
- Right side
- Loss of sensory function
- Loss of motor function
127
What is anosmia?
Loss of sense of smell. Commonly caused by a loss of smell
128
Damage to what nerve results in a loss of smell.
Olfactory nerve. Secondary to shearing forces or basilar skull fracture. Intracranial tumours at the base of the frontal lobes can interfere with olfaction
129
What results in issues in both eyes?
-Involvement of optic chiasm or further back results in issues with both eyes as optic nerve fibres cross at the optic chiasm. Pituitary tumours can cause these issues
130
What can results in vision loss in the eye?
-Lesions involving the retina or optic nerve can cause visual disturbance affecting only one eye
131
What are the effects of impingement of the oculomotor nerve?
- Pathology can cause pupillary dilation and/or double vision
- Down and out position with severe ptosis
132
What can cause impingement/damage to the oculomotor nerve?
- Raised intracranial pressure
- Aneurysms
- Vascular
- Cavernous thrombosis
- Oculomotor nerve runs on the tentorium cerebelli can be squashed unchus due to increased intracranial pressure.
133
What are the effects of impingement of trochlear nerve?
-Diplopia (rare and often subtle)
134
What can damage/impinge the trochlear nerve?
- Head injury is the most common cause
- Raised intracranial pressure
- Congenital palsies
135
What is a blow out fracture?
- A punch in the orbit which leads to increased pressure in the orbital cavity
- Floor of the orbit can crack and infraorbital nerve(maxillary branch) is very vulnerable
- Leads to reduced sensation in the lower eyelid and lower cheek
136
What is the effect of local anaesthetic injected in the mandibular foracment?
- Loss of sensation in the chin and lip due to the inferior alveolar nerve
- Loss of sensation at the side of the tongue due to lingual nerve
137
What does the inferior alveolar nerve becomes as it exits the inferior mandibular canal?
Mental nerve
138
What is trigeminal neuralgia?
Shingles of the trigeminal nerve
139
What do patients with injury to the cranial nerve 6 present with?
Dipoplia
140
What is the common cause of injury to cranial nerve 6?
- Raised intracranial pressure due to bleed or tumour
- Nerve easily stretched due to emerging anteriorly at point-medullary junction before running under the surface of the pons upwards towards the cavernous sinus
141
What is the facial nerve closely related to?
- Cranial nerve 8 as both run in posterior cranial fossa and enter the internal acoustic meatus
- Close relationship to the middle ear as it travels through the petrous part of the temporal
- Close relationship to the parotid but doesn't supply
142
What is affected with injury to the vestibocochlear nerve?
-Dysfunction in balance and hearing
143
What is an acoustic neuroma?
Benign tumour involving the vestibocochlear nerve. It impinges the nerve. Schwaan cells mostly.
144
What is presbyacusis?
Old age related hearing loss
145
Which nerve can be affected by inflammation at the back of the throat?
Glossopharyngeal which gives referred pain
146
What does deviation of the uvula indicate?
Uequal rise in the soft palate due to weakness so therefore the uvula is drawn towards a direction. This can be due to vagus nerve damage
147
What are the sign of damage to recurrent laryngeal nerve?
Hoarseness and dysphonia
148
Where does the accessory nerve run in the neck?
Posterior triangle
149
What is the significance of the region that the accessory nerve run in the neck?
-Susceptible to damage in the area e.g lymph node, biopsies, surgery and stab wound
150
What are the effect of damage to hypoglossal nerve?
Weakness and trophy of muscles of the tongue
151
What are the effect of the sympathetic innerveatin to the head and neck?
- Pulpillary dilation (dilator palpillae)
- Assits in eyelid retraction
- Vaso-constrciton of blood vessls
- Sweating
- Fight or flight
152
What are the effector tissues affected by the sympathetic nervous system?
- Eye
- Eye lid (superior tarsal muscle)
- Blood vessels
- Sweat glands
153
Where does the sympathetic nervous system emerge from?
T1-L2
154
How do the sympathetic fibres get to the head and neck?
Hitch hike on blood vessels such as the internal and external carotid then onto the trigeminal nerve
155
Why does partial ptosis occur when the sympathetic fibres are impinged?
- Loss of supply to the surperior tarsal muscle
| - Occulomotor nerve supplies the rest of the eyelid so only partial ptosis
156
What is the path taken by the autonomic fibres?
- Arise from brainstem
- Hitch hike onto one of 4 cranial nerves
- Pass to the ganglia
- Hitch hike on cranial nerve 5
- Target tissue
157
What are the target tissue of the parasympathetic innervation ?
Both muscle in iris for constriction and ciliary muscle
- Lacrimal glands
- Mucosal lands
- Salivary glands
158
What is the action of the parasympathetic innervation when a light is shone in the left eye?
Direct Constriction of the left pupil
| Consensual constriction of the right eye
159
What is the effect of decreased parasympathetic innervation from the facial nerve?
- Reduced effect on sublingual and submandibular glands
- Reduced effect on the lacrimal gland
- Reduced effect on nasal and oral mucosal glands
- Can cause dry eyes and mouth if interrupted
160
What gland is parasympathetically innervated by the glossopharyngeal nerve?
Parotid gland
161
What is parasympathetically innervated by the vagus nerve?
- Glands in the laryngopharynx
- Larynx
- Glands and smith muscle of the oesophagus and trachea
- Heart
- Smooth muscle and land with respiratory and GI tract
162
What can pathology involving apex of the lung and internal carotid artery cause?
Autonomic dysfunction in the eye and face
163
What are the signs of a pancoast tumour?
Horner's syndrome
- Partial ptosis
- Miosis
- Anhydrosis
164
Outline the pupillary light reflex?(start from the left eye)
- Sensory afferent from left retina
- Some branches leave CNII to enter midbrain
- Connection with edinger westphal nuclei
- Parasympathetic fibres from EDW leave the brainstem
- Hitch hike on the oculomotor nerve
- Passes via ciliary ganglion
- Reach the sphincter papillae
- Direct light reflex and consensual light relex
165
What are the two main branches of the facial nerve arising inside the petrous bone?
- Greater petrosal nerve
| - Chorda tympani nerve
166
What is the parasympathetic route to the submandibular and sublingual glands?
- Facial nerve emerges from brainstem
- Hitchhikes the pre-ganglionic parasympathetics (CN VII) into petrous bone
- COntinues along facial nerve
- JOins chorda tympani nerve
- Crosses the middle ear cavity
- Exits base of the skull
- Submandibular ganglion
- Leaves via Post ganglionic (CN V) to the submandibular and sublingual salivary glands
167
What is the parasympathetic route to the lacrimal, nasal and mucosal glands?
- Facial nerve emerges from brainstem
- Hitchhikes the pre-ganglionic parasympathetics (CN VII) into petrous bone
- At geniculate ganglion, greater petrosal nerve leaves to pterygopalatine fossa
- Interacts with the pterygopalatine ganglion
- Hitch hikes the trigeminal nerve to Lacrimal gland and nasal and oral mucosal glands
168
What is the path of the parasympathetic to the parotid gland?
- Pre-ganglionic parasympathetics arise from the brainstem with Cranial nerve 9 and into the jugular foramen
- Leaves via the Tympanic nerve
- Joins tympanic plexus
- Leaves the tympanic plexus via the lesser petrosal nerve through the foramen ovale
- Interacts with the otic ganglion
- Post ganglionic parasympathetics then with hike on branch of mandibular branch of trigeminal nerve
- Parotid gland
169
What is the route of parasympathetic innervation of the vagus nerve?
- Medulla of the Brainstem
- Parasympathetic fibres hitch hikes on CN X and its branches
- Meets ganglion at or in target tissue
170
Which bone are parts of the ear found?
-Temporal bone
171
What is Ramsay hunt syndrome?
- Chicken pox of the facial nerve
| - Geniculate ganglion affected by reactivation of the chicken pox virus
172
What is cauliflower ear?
- Secondary to blunt injury to the pinna
- Accumulation of blood between cartilage and perichondrium
- Ischaemia of the cartilage leading to necrosis due to lack of blood supply
- If untreated or poorly treated it can lead to fibrosis and new asymmetrical cartilage development leading to cauliflower ear
173
How can cauliflower ear be treated?
- Prompt drainage of the haematoma and measures to prevent re-accumulation and re-apposition of two layers are necessary
- Provides the cartilage back its blood supply
174
What is the purpose of the arrangement of hairs and production of wax in the ear canal?
- Prevent objects entering deeper into ear canal
| - Aids in desquamation and skin migration out of canal
175
How long is the external acoustic meatus?
-2.5 cm
176
What is the effect of facial nerve lesion on the middle ear?
- Tensor tympani and stapedius are no longer innervated
- Excessive vibrations are no longer impeded
- Patient presents with hyperacousis
177
What is otosclerosis?
- Ossicles fused at articulations in particular between base plates of stapes and oval window
- Sound vibrations cannot be transmitted
- Causes deafness
178
What is glue ear?
- Build of fluid and negative pressure in middle ear
- Due to Eustachian tube dysfunction and can predisposes to infection as the fluid is the ideal growth medium for bacteria
- Decreases mobility of TM and ossicles affecting hearing
179
How is glue ear treated?
- Most resolve spontaneously in 2-3 months but some may persist
- May require grommets to ventilate middle ear. Equilibriation of pressure is the purpose of the grommet
180
What is acute otitis media?
- Acute middle ear infection
| - More common in infants, children than in adults
181
What is the symptoms of acute otitis media?
- Otalgia
- Temperature
- Red +/- bulging TM and loss of normal landmarks
182
Why is acute otitis media more common in children?
- Pharygotympanic tube is shorter and more horizontal in infants
- Easier passage for infection from nasopharynx to the middle ear
- Tube can block more easily, compromising ventilation and drainage of middle ear, increasing risk of middle ear infection
183
What are some complication of acute otitis media?
- Tympanic membrane perforation
- Facial nerve involvement
- Mastoiditis
Intracranial complications
- Meningitis
- Sigmoid sinus thrombosis
- Brain abscess
184
What is mastoiditis?
- Middle ear cavity communicates with mastoid air cells via mastoid antrum and auditus.
- Provides a potential route for middle ear infections to spread to mastoid bone
185
Which nerve can be affected by middle ear pathology?
- Facial nerve
| - Chorda tympani branch may be involved as it runs through the middle ear cavity
186
What is cholesteatoma?
- Abnormal skin growth growing into the middle ear eroding strructures such as ossicle, mastoid bone, cochlea
- Not malignant
- Usually secondary to chronic ear infections or secondary to Eustachian tube dysfunction
187
What are the symptoms of choleastoma?
- Painless
- Often Smelly otorrhea
- Sometimes Hearing loss
188
Which regions normally lead to sensorineural hearing loss?
Inner ear
189
Which regions normally lead to conductive hearing loss?
- Middle ear
| - External Ear
190
How can we hear?
- Auricle and external auditory canal focuses and funnels sound waves towards tympanic membrane which vibrates
- Vibration of ossicles sets up vibrations in cochlear fluid
- Sensed by sterocilia in cochlear duct
- Movement of the stereo cilia in organ of Corti trigger action potentials in cochlear part of cranial nerve VIII
- Primary auditory cortex
191
What are examples of diseases of middle ear?
- Merniere's disease
- BPPV
- Labrynthitis: inner ear infection
192
What are the symptoms and signs of inner ear?
- Vertigo
- Hearing loss and tinnitus
- Nystagmus
193
What are some causes of sensorineural hearing loss?
- Presbyacusis
- Meniere's disease
- Acoustic neuroma
- Ototoxic medications
194
What is transmitted through the apex of the orbital cavity?
- Superior orbital fissure
- Inferior orbital fissure
- Optic canal
195
What protect the eye ball from injury?
Tough orbital rim
196
What are the important anatomical reactions of the orbit?
- Paranasal air sinuses
- Nasal air cavity
- Anterior cranial fossae
197
What are the implications of the anatomical relation of the orbit?
- Orbital trauma
| - Spread of infection
198
What are the weakest parts of the orbital cavity?
- Medial wall
| - Floor of the orbit
199
What are the features of an orbital blow out fracture?
- History of trauma to the eye
- Painful periorbital swelling
- Double vision
- Impaired vision
- Anasthesia over affected cheek on affected side
200
How does an orbital blow-out fracture occur?
-Sudden increase in intra-orbital pressure fractures floor of the orbit
201
What are the effects of an orbital blow out fracture?
- Orbital contents and blood can prolapse into maxillary sinus
- Structures can be trapped at the fracture site such as extra orbital muscle near floor or orbit
202
What separates the eyelid fat and orbicularis oculi muscle?
Orbital septum
203
What is the function of the orbital septum?
Acts as a barrier against infection spreading from the pre-septal space to post-septal
204
What is peri-orbital cellulitis?
- Cellulitis of orbital structures.
- Can be pre-septal or post-septal
- Increasing degrees of severity
205
What are the precursors to periorbital cellulitis?
- Bites
- Periorbital trauma
- Sinuses (fronto-ethmoidal)
206
What are the complication of periorbital cellulitis?
- Abscess formation
- Spread of infection intracranially
- Cavernous sinus thrombosis
207
Which veins can infection of the orbit spread through?
- Opthalmic veins
- Pterygoid venous plexus
- Facial vein
208
What is a meibomian cyst?
- Blockage of a meibomian gland.
| - Prevention of evaporation of tear film and spillage is affected
209
What is a stye?
-Infection of the eyelash follicles
210
Is the cornea covered by the conjunctivae?
No. The conjunctivae extends to the limbus which is the edge of the cornea and reflected on the inner surface of upper and lower eyelid.
211
What is conjunctivitis?
When the conjunctiva become inflamed, blood vessels dilate and eye appears red.
212
What is a subconjuctival haemorrhage?
-Haemorrhage from blood vessels in conjunctiva that is readily visible
213
Where does the blind spot lie on the opthalmascope?
Medially on optic disc. Where the optic nerve is transmitted
214
What is glaucoma?
-Drainage of aqueous humour from anterior chamber can be blocked. Can lead to irreversible damage and death of the optic nerve
215
What is an open angle glaucoma?
- Deteriorton of trabecular meshwork
- Aqueous humour cannot drain to the canal of Schlemm
- Present with visual field loss and cupping of the optic disc
-Chronic (age)
216
What is a closed angle glaucoma?
- Narrowing of iridocorneal angle
- Rapid rise in the intra-ocular pressure
- Presents with sudden onset of painful red eye, blurred vision, fixed or sluggish semi dilated oval shaped pupil, nausea, vomiting
- Acute
217
What is the effect of the glaucoma?
- Rise in intra-ocular pressure and damage to optic nerve
- Optic disc cupping occurs
- Sight threatening
218
What is the accommodation reflex?
- Light rays from near-objects are more divergent and require greater refraction to being them into focus on retina
- Autonomic constriction of the pupil
- Eyes converge
- Lens becomes more biconcave due to contraction of the ciliary muscle
219
Which extra-ocular muscles are not supplied by the oculomotor nerve?
- Lateral rectus by the abducens nerve
| - Superior oblique by Trochlear
220
How do we isolate the action of superior oblique?
- Move the eyeball to a medial position
| - Move the eyeball down
221
How do we isolate inferior rectus?
- Move the eyeball into the lateral position
| - Move the eyeball down
222
How do we isolate the action of inferior oblique?
- Move the eyeball into the medial position
| - Move the eyeball up
223
How do we isolate the action of superior rectus?
- Move the eyeball into the lateral portion
| - Move the eyeball up
224
What is sialolithiasis?
- Salivary stones.
- Most are located in the submandibular glands
- Leads to dehydration and reduced salivary low
225
What are the symptoms of sialolithiasis?
- Pain in gland
- Swelling
- Infection
226
What is used to investigate salivary stones?
Sialogram
227
What are the symptoms of tonsillitis?
- Fever
- Sore throat
- Pain/difficulty swallowing
- Cervical lymph nodes
- Bad breath
228
How do peritonislar abscesses form?
- Can follow on from tonsillitis
| - Can arise on its own
229
What are the symptoms of peritonsillar abscess?
- Severe throat pain
- Fever
- Bad breath
- Drooling
- Difficulty opening mouth
230
What is found in the oropharynx?
Palatine tonsils between Palatoglossus and Palatopharyngeal
231
What is found in the laryngopharynx?
Piriform fossa
232
What is Killian's dehiscence?
Weakness found between the thyropharyngeal and cricopharyngeal muscle. These 2 are parts the inferior constrictor muscle
233
What is a pharyngeal pouch?
A posteriomedial (false) diverticulum. Could be due to
- Failure of the upper oesophageal sphincter to relax
- Abnormal timing of swallowing
- Essentially there is higher pressure in laryngo pharynx
- Weakness between muscle belly of the inferior constrictor muscle produces out pouching of pharyngeal mucosa
234
What are the symptoms of pharyngealal pouches?
- Dysphagia
- Bad breath
- Regurgitation of food
- Occasional choking on fluids
- General difficulty swallowing
235
What are the symptoms of pharyngeal pouches related to?
Food material collecting in pouch or disruption of swallow
236
What are some causes of dysphagia?
Stroke
Progressive neurological disease
COPD
Dementia
237
What are signs and symptoms of dysphagia?
- Coughing and choking
- Sialorrhoea
- Recurrent pneumonia
- Change in voice/speecj
- Nasal regurgitation
238
Which bones in the facial skeleton are more susceptible to fracture?
- Nasal bone due to prominence
- Zygomatic bone
- Mandible
239
How the pituitary gland be accessed?
Through the nasal cavity through the sphenoid
240
What is a septal hematoma?
- Cartilaginous part of the septum takes blood supply from the overlying perichondrium
- Trauma to nose can lead to buckling of the septum and shearing of blood vessels
- Blood accumulates between the perichondrium and cartilage
241
What is the effect of untreated septal haematoma?
- Avascular necrosis of cartilaginous septum
- Saddling of nasal dorsum
- Can develop infection in the collecting haematoma
- Septal abscess formation further increases likelihood of avascular necrosis of septum
242
What are nasal polyps?
- Swelling of nasal mucosa
- Usually bilateral
- Pale or yellow in appliance/fleshy and reddened
243
What are the symptoms of nasal polyps?
- Blocked nose and watery rhinorrhoea
- Post nasal drip
- Decreased smell and reduced taste
- Unilateral polyp +/- blood tinged secretion may suggest tumour
244
What is rhinitis?
-Inflammation of the nasal mucosal lining
245
What are symptoms of rhinitis?
- Nasal congestion
- Rhinorrhoea
- Sneezing
- Nasal irritation
- Post nasal drip
246
What are common causes of rhinitis?
- Acute infective rhinitis (common cold)
| - Allergic rhinitis
247
What is epistaxis?
Nose bleed
| -Mucosa and blood vessels easily injured
248
Which branches does the arterial supply to the nasal cavity arise from?
- Ophthalmic artery
| - Maxillary artery
249
What is formed in the anterior septum?
```
Arterial anastomoses (Kiesselbach's area)
-Most common source of bleeding in epistaxis
```
250
What is the relevance of the venous drainage from the nasal cavity?
- Pterygoid venous plexus
- Cavernous sinus
- Facial vein
This means infection can spread intracranially
251
Which type of epistaxis is potentially more serious?
- Bleeding from the sphenopalatine artery
| - Potentially more serious and difficult to treat
252
What are paranasal sinuses?
- Air filled extensions of nasal cavity which are lined by respiratory mucosa
- Helps to humidify and warm inspired air
- Drain into the nasal cavity via mall channels called Ostia into the meatus
253
What is acute sinusitis?
-Acute inflammation of lining of sinus. Commonly infective and often secondary to viral infection of nasal cavity
254
What are symptoms of acute sinusitis?
- Non resolving cold or flu like illness
- Pyrexia
- Blocked nose and rhinorrhoea (yellow/green discharge)
- Headache/facial pain
255
What is the pathophysiology of acute sinusitis?
- Primary infection leads to reduced ciliary function, oedema of nasal mucosa and sinus Ostia and increased nasal secretions
- Drainage from sinus is obstructed
- Stagnant secretion within the sinus become ideal breading ground for bacteria (secondary infection)
- Caused by dental infections and respiratory infections.
256
How can the cricothyroid membrane be used in an emergency?
-Emergency access to provide patent airway for the patient
257
What forms the vocal and vestibular ligament?
- Quadrangular membrane forms the vestibular ligament
| - Upper free border of cricothyroid ligament-thickened edge forming the vocal ligament
258
What is found between the vestibular and vocal folds?
Ventricle which leads laterally and upwards into the saccule. Contains mucus glands that keep vocal folds moist
259
What is the epithelium lining of the larynx?
Pseudo-stratified ciliated columnar epithelium
-Stratified squamous epithelium on the true vocal cord lining
260
What is the purpose of the laryngeal muscles?
- Closing of the larynx during swallowing to protect the respiratory tract
- Act to open larynx and allow movement of air during inspiration and expiration
- Control movement of vocal cords in phonation and in cough reflex
261
Which intrinsic muscle isn't supplied by the recurrent laryngeal nerve of the vagus?
-Cricothyroid muscle which is supplied by external branch of superior laryngeal nerve
262
What is the position of the vocal cords in deep breathing?
-Widely abducted
263
What is the position of the vocal cords during phonation?
-Adducted
264
What leads to hoarseness of voice especially when attempting high pitched sounds?
- Injury to the external branch of superior laryngeal nerve
| - Closely related to the superior thyroid artery
265
What does the recurrent laryngeal nerve supply?
- Sensory to subglottic
| - Motor to the intrinsic muscles (except cricothryoid)
266
What does the superior laryngeal nerve supply?
- Sensory to the supraglottic
| - Motor to the Cricothyroid
267
What is the path of the recurrent laryngeal nerve?
- Arises distally
- Loops under the right Subclavian artery on the right
- Loops under the arch of aorta on the left
- Ascends the tracheo-oesophaageal groove
- Close relationship with inferior thyroid arteries supplying thyroid gland
268
What are the causes of vocal cord palsies?
- Thyroid Surgery causes damage to the nerve due to reaction with he inferior thyroid artery
- Aortic arch aneurysm (LRLN)
- Cancer involving the apex of the lung (RRLN)
- Disease or surgery involving larynx, oesophagus or thyroid
269
What is the effect of unilateral lesion of the RLN?
- Paralysed vocal cord assumes a paramedian position between fully abducted and fully adducted
- Unilateral palsies may lead to hoarseness of voice and sometimes ineffective cough
- Often the contralateral sides compensates in time
270
What is the effect of bilateral lesion of the RLN?
- Both vocal cords paralysed and in paramedic position
- Narrow glottis
- Significant airway obstruction. Needs an emergency surgical airway
271
What are the signs of bilateral vocal cord palsies?
- Cyanosis
- Hypoxia
- Distress
- Raised respiratory rate
- Stridal breathing
- Often more acute and dangerous
272
What are other conditions affecting the larynx?
- Laryngitis
- Laryngeal nodules
- Laryngeal cancer
- Croup
- Epiglottittis
- Laryngeal oedema
273
What are the common risk factors of head and neck cancers?
- Heavy alcohol use
- Heavy tobacco use
- Age
- Dental hygiene
- Males more than women
- EBV infection
- Chewing betel quid (Paan)
- Occupational/Environemntal exposure to certain inhalants
- Long term exposure to sunlight or sunbeams (lip)
- HPV
274
What is the common malignancy seen in head and neck cancers?
Squamous cell carcinomas
275
What is the general presentation of head and neck cancers?
- Unexplained painful and/or mucosal ulceration or lesion within the oral cavity (leukoplakia, eythroplakia, lump)
- Unexplained hoarseness of voice
- Dysphagia or Odynophagia
- Otalgia
- Cervical lymphadenopathy
276
What are the the typical investigations required to determine diagnosis and severe of HNC or thyroid cancer?
- Clinical examination
- Biopsy
- Imaging
- Endoscopic investigation
277
What are common causes of neck lumps?
- Thyroid cancer
- Hyperthyroidism
- Hypothyroidism
278
How is the severity of the HNC determined?
-TMN staging used (stage 1-4)
279
What is contained in the superficial cervical fascia?
Loose connective tissue containing
- Adipose tissue
- External jugular vein
- Cutaneous nerves
- Superficial lymph nodes
- Platysma muscle
280
Which structures are contained within the pretracheal fascia?
- Infrahyoid muscles
- Thyroid gland
- Trachea
- Oesophagus
281
What strutures are invested by the buccopharyngeal fascia?
- Muscles of pharynx
| - Muscles of oesophagus
282
Which structures are found within the carotid sheath?
- Common carotid artery
- Internal jugular vein
- Vagus nerve
283
Which structures are enclosed by the prevertebral fascia?
- Axillary vessels
| - Brachial plexus of nerves
284
What are the advantages provided by the deep cervical fascia?
- Allow structures to move and pass over one another with ease
- Allow separation of tissues during surgery
- Determine the direction and extent to which any infection occurring within the neck may spread
285
What are symptoms of a retropharyngeal abscess?
- Visible bulge in the oropharynx
- Sore throat
- Difficulty swallowing
- Stridor
- Reluctance to move neck
- High temperature
286
Why does the thyroid goitre move upon swallowing?
- Enclosed by pre-tracheal fascia which is attached to hyoid bone
- Hyoid bone and pharynx rise on swallowing so therefore any pathology swelling involving the thyroid moves with the space
287
What can retrosternal extension thyroid goitre lead to ?
- Compression of the structures running through the root of the neck such as the trachea and venous blood vessels
- Can lead to symptoms of stridor and breathlessness
288
What is the action of the muscles of mastication?
Move the mandible at the temperomandibular joint
289
What are the branches of the external carotid artery?
- Superficial thyroid artery
- Ascending cervical artery
- Lingual artery
- Facial artery
- Occipital artery
- Posterior auricular artery
- Maxillary artery
- Superficial temporal artery
290
How can infections spread intracrnailaly from the facial vein?
- Facial vein is connected to the pterygoid venous plexus and the ophthalmic vein
- Infection can track back into the dural venous sinuses
- Thrombophlebitis of facial vein involves infected clot
291
Which vein does the facial vein drain into?
Facial vein drains into the Internal Jugular vein
292
Where does an extradural haematoma form?
Between:
- Inner table
- Periosteal layer of dura
293
What does the vertebral arteries supply?
- Posterior parts of the brain
| - Posterior neck
294
What are the origin of the left and right common carotid arteries?
- Right Common Carotid Artery originates from Brachiocephalic Artery
- Left Common Carotid Artery arises from the arch of the Aorta (longer)
295
Where is the carotid sheath derived from?
Fusion of:
- Prevertebral fascia
- Investing layer
- Pretracheal fascia
Arteries run behind the sternocleidomastoid. Thin shath over veins and thicker sheath over arteries
296
What are the terminal branches of the external carotid artery?
- Superficial temporal artery
| - Maxillary artery
297
What are some complications of a septic thrombi in the facial vein?
- Superior and Inferior ophthalmic vein connected to the facial vein
- Septic thrombi can travels to cavernous sinus
- Can cause a cavernous sinus thrombosis
298
Which blood vessels are more likely to be affected if damage affects the dense connective tissue and what are the implications of this?
- Artery
- If open wound, there will be profuse bleeding. Blood vessels are adhered to the dense connective tissue so less ability to vasoconstrict.
- If close wound, well localised lump form. The dense connective tissue stop spread of bleeding beyond the confines of the area of damage
299
Why might an incised scalp gape open if injury affects the aponeurosis?
- Aponeurosis is attached to frontalis anteriorly and occipitalis posteriorly.
- The pull of these muscles causes wound to gape open
- Profuse bleeding
300
Which blood vessels are likely to be damaged in the loose connective tissue and why does it spread?
- Veins
| - Loose connective tissue allows the blood spread within the layer.
301
Which nodes is often enlarged in tonsillitis?
Jugulo digastric
302
What does the jugulodigastric node drain and where does it lie?
- Palatine tonsil
- Oral cavity
- Tongue
Below angle of mandible
303
What does the jugulo-omohyoid nodes drain and where do they lie?
- Tongue
- Oral cavity
- Trachea
- Oesophagus
- Thyroid gland
Any infection affecting these areas results in the nodes swelling
304
What is trosier's sign?
Enlarged, hard, left supraclavicular lymph nodes secondary to metastatic abdominal malignancy
305
Which tonsil is readily seen on routine examination of a patient?
Palatine tonsils
306
Which tonsils are known as adenoids?
- Pharyngeal tonsils
| - Located in roof of nasopharynx behind the uvula
307
How can pharyngeal tonsils contribute to ear infections?
- Close to the Eustachian Tube
| - Can block the tube when enlarged thereby contributing to middle ear infection
308
Which region is responsible for motor function for one half of the body?
-Primary motor cortex in the pre-central gyrus in the fontal lobe
309
What is region gespoble for general sensory perception of one half of the body?
-Primary somatosensory cortex in the parietal lobe
310
What connective tissue is located in the longitudinal fissure?
-Falx cerebri
311
What is found running between inferior part of the occipital lobes and the cerebellum below?
-Tentorium cerebelli
312
How does a corpus callostomy benefit patients with epilepsy?
Prevents severe epilepsy occurring as the lobes of the brain cannot communicate with each other which can prevent muscles on each side working together
313
Between which meningeal layers can the CSF be found?
-Arachnoid and Pia
314
Where within the brain is CSF?
Ventricles
315
How do the pre ganglionic sympathetic fibres synapse with the post ganglionic sympathetic fibres?
- Pre ganglionic fibres ascend from the thorax and synapse with one of the upper cervical ganglia of the chain in the superior and middle cervical ganglia.
- Post ganglionic fibres reach their target tissues in the head and neck by hitch hiking onto blood vessels
316
What are the parts of the temporal bone?
- Squamous part
- Petromastoid part
- Tympanic plate
- Styloid process
317
What is the mastoid process?
- Palpable landmark posterior to the pinna
| - Cavity of the mastoid antrum extends into the mastoid process and communicates with air cells
318
What forms the wax in the external auditory meatus?
-Cerumen from skin lining and discarded cells of the skin
319
How does the sensation of the ear popping occur?
- Eustachain tube is normally closed
- Salpingopharyngeus
- Pull of attached palate muscle when swallowing or yawning cause it to open
- This is noticed as ears popping
320
What are the ossicles called found in the middle ear?
- Malleus
- Incus
- Stapes
321
What equipment is used to examine the external auditory canal inspected?
- Otoscope
| - Speculum
322
How is the external auditory canal straightened for examination?
-Up, back and out for better visualisation
In children down and back
323
How can the eye be placed at risk with a facial nerve injury?
- Can't close eye to protect from dust and foreign objects
| - Can't lacrimate the eye
324
Which nerve supplies the carotid sinus?
-Afferent nerve is the 'Glossopharyngeal nerve'
325
What is the purpose of the Weber's test?
Lets you know which side is affected but not whether it is sensorineural or conductive
326
What are the results of a normal person in a Rinner's and Weber's test?
- Air Conduction>Bone Conduction
| - Centre
327
What are the results of a conductive hearing loss in a Rinner's and Weber's test?
- Bone Conduction>Air Conduction
| - Louder at the affected ear in Weber's test
328
What are the results of a sensorineural hearing loss in a Rinner's and Weber's test?
- Air Conduction>Bone Conduction
| - Louder at the unaffected ear in Weber's test
329
Describe the theory behind the Weber's Test
- Normal ambient sounds are conducted
- The ringing is conducted to the inner ear
- If the conductive affect the normal ambient sounds aren't transmitted so the sound from the tuning fork is heard louder
- If sensorinerual, the ambient sounds are heard more than the tuning fork so the sound in heard louder at the unaffected side
330
What are the 3 layers of the eye?
- Sclera (fibrous and tough)
- Chorioid (Vascular and muscular)
- Retina (rods and connes)
331
What connects the choroid and iris?
-Ciliary body which is vascular and muscular
332
What is uveitis?
- Inflammation of the choroid layer
- Presents with a red and painful eye which is worse when focusing or attempting to look at bright lights
- Autoimmune associated (AS, IBS)
333
What is the purpose of pigment layer and where does it lie?
- Between the choroid and retina
- Cells contain melanin
- Plays a role in helping absorb scattered light that has passed into the eye.
- Reduces reflection and allow us to focus images appropriately on the retina
334
How is vision affected in people with albinism?
- Lack of melanin in pigmented layer
| - Wear glasses to prevent the scattering of light
335
What is the macula?
- Concentration of rod cells
- Cone cells have high visual acuity
- Centre of the macula is the fovea and has a rich density of only cones
336
What is retinal detachment?
- Pigmented epithelial cell layer can detach from neurosensory cell layer in certain layer
- Photoreceptors at the site of detachment are no longer able to function resulting in visual disturbance (lack of blood supply)
337
What is the purpose of the rods?
- Vision in low light
- Doesn't discern colours.
- Abundant in the periphery
338
Where is the anterior chamber?
-Space between cornea and Iris
Filled with aqueous humour
339
Where is the posterior chamber?
-Space between the Iris and lens
Filled by aqueous humour and ciliary body and processes found in this chamber
340
What are cataracts?
Degradation of proteins in the lens which can cause it to become clouded and less transparent. Occur gradually
341
Which two muscles are found in the iris and what is their purpose?
- Sphincter pupillae and dilator pupillae
| - Acts to control the size of the pupil and are controlled bt the autonomic nervous system
342
What is presbyopia?
As we age
- Lens becomes dense, less elastic and more difficult to change shape
- Thus, the ability to accommodate and focus on near-objects becomes impaired as well get older
343
What is the hole on the medial side of the lower eyelid and its purpose?
- Puncta
| - Collects tears
344
What are the steps to take clinical examination of the eye?
IVA FROM
I - Inspection of the eye
VA - Visual acuity tested using Snellen Chart
(V)F - Tested using Confrontation
R - Test te reflex. Direct and consensual reflex and accommodation reflex.
O - Use of an ophthalmoscope to visualise back of the eye.
M - Test the eye movements
345
What does the nasal septum consists off?
- Perpendicular plate
- Ethmoid bone
- Septal cartilage
- Vomer
346
What are the four major paranasal sinuses?
- Maxillary
- Frontal
- Ethmoidal
- Sphenoid
Maxillary narve supply
347
Which sinus is most prone to infection and why?
-Maxillary sinus and because of the location of its opening high on the wall of the nasal cavity.
348
What is the purpose of the turbinates?
Increase surface area in order to warm, humidify and slow down air
349
Where does the olfactory nerve run in the nasal cavity?
Upper part of the nose
350
What are the borders of the oral cavity?
Anterior: Oral fissure
Posterior: Oropharyngeal isthmus
Lateral and medial wall: Anterior and posterior pillars of faucet formed by the palatoglossus anteriorly and the palatopharyngeal posteriorly
351
What are the innervations of the extrinsic muscles of the tongue?
Hypoglossal nerve
- Genioglosus
- Styloglossus
- Hyoglossus
Vagus nerve
-Palatoglossus
352
Where are the parts of the pharynx located?
Nasopharynx - C1
Oropharynx - C2-C3
Laryngopharynx - C3-C6
353
What is located externally on the walls of the pharynx?
- Superior constrictors
- Middle constrictors
- Inferior constrictors
354
What innervates the constrictors of the pharynx and what is their action?
Vagus nerve
Relax and contrat to propel bolus into the oesophagus
355
Which parts of the pharynx and soft palate are supplied by the vagus nerve?
-All the muscles of the pharynx except stylopharyngeus
356
What is the sensory innervation of parts of the pharynx?
Nasopharynx - Maxillary Nerve
Oropharynx and Eustachian tube - Glossopharyngeal Nerve
Laryngopharynx - Vagus Nerve
357
What happens to the pharyngeal tonsils in adulthood?
They atrophy after puberty
358
What is a potential site for foreign bodies in the larygngopharynx?
- Piriform fossa is a potential site
| - Also a site for cancer
359
Where is the larynx found?
- Hyoid bone superiorly
| - Trachea below
360
What does the larynx consist of?
-Series of cartilages and bone held together by membranes, ligaments and muscles
361
What are the regions of the larynx?
- Supraglottis
- Glottis
- Subglottis
362
What joins the hyoid bone and thyroid cartilage?
-Thyrohyoid membrane
363
What joins the cricoid cartilage and thyroid cartilage?
-Cricothyroid membrane
364
What forms the structural framework of the larynx?
- Epiglottis
- Thyroid
- Cricoid
- Arytenoid cartilages (paired)
365
What connects the epiglottis and arytenoid cartilages?
Aryepiglottic folds
366
What are the structural features of the cartilages of the larynx?
- Thryoid is shield like and has a laryngeal prominence.
- Cricoid cartilage is signet-ring shaped. It is the only complete ring of cartilage in the respiratory tract
- Arytenoid sits on top of the cricoid cartilage posteriorly one on each side
367
What are the two folds of mucosa lining the interior of the larynx?
- Vestibular fold (false vocal cords)
| - True vocal cord containing vocal ligament.
368
What is the space found between the true vocal cords?
-Rima glottis
369
Which is the only intrinsic muscle that abducts the vocal cords to allow breathing?
-Posterior Cricoarytenoid
370
What are the cervical nerve roots for the cervical plexus?
C1-C4
371
What is the ansa cervicialis?
Supply the infrahyoid muscles
Nerve roots: C1-C3
Action: Motor
372
What does the ansa cervicalis overlie?
Scalene muscle
373
Which nerve roots supply the phrenic nerve?
C3-C5
| Diaphragm
374
Which areas of the scalp are supplied by the cervical plexus?
-Posterior to superior scalp
375
What relationship does the posterior border of the sternocleidomastoid have with the sensory branches of cervical plexus?
-Overlie the sensory branches
376
What is Erb's point?
- Sensory nerves enter the skin at the middle of the posterior border of the sternocleidomastoid
- Cervical plexus nerve block
- Anaesthetic is injected at this point as a regional block
377
The thyroid gland is palpable. True/False
False. Not usually palpable unless it is enlarged (goitre)
378
Which situations cause a goitre in thyroid gland?
Hyperthyroidism - Graves
| Hypothyroidism - Hashimoto's
379
Where are the parathyroid glands and how many are there?
4 parathyroid glands
Lie beneath the thyroid
Control calcium levels
380
Which muscle overlie the thyroid gland?
-Infrahyoid muscles
Strap like muscles
381
What are the extrinsic longitudinal muscles muscles of the pharynx?
- Stylopharygeus (glossopharyngeal)
- Palatopharyngeus (vagus)
- Salpingopharyngeus (vagus)
382
What is the function of the extrinsic longitudinal muscles of the pharynx?
- Elevation of the larynx
| - Widen and shorten the pharynx
383
Why does the bleed from the loose connective tissue cause ecchymosis?
- The loose connective tissue is under the aponeurosis.
- The aponeurosis is attached to the frontalis muscle anteriorly. Frontalis muscle is attached to obicularis oculi and subcutaneous tissue.
- Blood can track in this layer to the extraoccular muscles
- Causes ecchymosis
