clinical questions

Question 1

significance of pterion

Answer 1

-junction of frontal, temporal, parietal and greater wing of sphenoid joining together
-weak area
-overlies middle meningeal artery
-trauma to this area can lead to epidural haematoma

Question 2

what would happen if there is fracture to cribriform plate?

Answer 2

• CSF rhinorrhoea
  (leakage of CSF into nasal cavity)

Question 3

what would occur if there is damage to facial nerve at site of internal acoustic meatus?

Answer 3

• effect on muscles of facial expression nd the stapedius muscle which will result in hyperacusis (inability to tolerate high pitched sounds)

Question 4

what is not formed a birth and what can occur as a result?

Answer 4

At birth the mastoid process has not formed & CN VII is at risk of compression/injury during forceps delivery leading to paralysis of the facial muscles

Question 5

what would occur if there was a central lesion in the brain?

Answer 5

the upper half of the face would still be innervated (patient could still wrinkle forehead)

Question 6

what would occur if there was a peripheral lesion in the brain?

Answer 6

whole of one side of the face is not innervated (patient could not move forehead) – bells palsy
(All fibres of facial nerve effected)

Question 7

what dislocation of TMJ is more common and why?

Answer 7

anterior dislocation is more common because the postglenoid tubercle prevents posterior dislocation

Question 8

what percentage of people have a TMJ disorder?

Answer 8

40-75%

Question 9

what is a concern during neck surgery?

Answer 9

damage to the right recurrent laryngeal nerve which could cause hoarseness or aphonia

Question 10

what in the neck is more vulnerable during childhood?

Answer 10

Cervical pleura – as it is higher in them because of the shorter necks
Wounds at the base of the neck may compromise the lungs and pleural sacs resulting in pneumothorax.

Question 11

what will occur due to damage to cervical sympathetic trunk?

Answer 11

Horner’s Syndrome
absence of sympathetically stimulated functions on ipsilateral side of head
-Constriction of pupil (miosis)
-Drooping of superior eyelid (ptosis)
-Vasodilation & absence of sweating on face/neck (flushed face & anhydrosis)

Question 12

what are pancoast tumours and what do they cause?

Answer 12

-tumours located in the apex of the lung involving the apical chest wall & structures of the thoracic inlet
causes : -Horner syndrome
-Severe pain in the shoulder
-Atrophy of hand & arm muscles
-Obstruction of the subclavian vein resulting in oedema of upper arm

Question 13

scalp layers and spread of infection- how do these infections spread, where and why

Answer 13

Between the aponeurosis & pericranium there are potential spaces for accumulation of fluid (e.g. blood) or spread of infection
-Fluid/infection can spread to the eyelids or root of nose because rontal belly of occipitofrontalis inserts into skin & subcutaneous tissue not bone
- spread via emissary vein

Question 14

what passes through cavernous sinus and significance of this

Answer 14

CN III (occulomotor)
CN IV (trochlear)
CN V1 (ophthalmic branch of trigeminal)
CN V2 (maxillary branch of trigeminal)
CN VI (abducens)
Internal carotid (and the sympathetic fibres on the carotid)

• if infection tract back into it, there can be some nasty consequences like meningitis and cavernous sinus thrombosiswhich will generally present as problems involving those nerves.

Question 15

importance of circle of willis

Answer 15

-circular loop allows for equalisation of blood flow between the 2 hemispheres

-Essential in case an artery becomes compromised (occlusion, constriction, etc.) as blood supply is maintained via collateral circulation

Question 16

pathologies of salivary glands

Answer 16

-mumps
-salivary stones
-excessive salvation (ptyalism)

Question 17

what is mumps

Answer 17

viral infection that presents in children as painful swellings over the salivary glands; most commonly over parotid glands

Question 18

what salivary duct is most likely to get salivary stones and why ?

Answer 18

submandibular duct due to its upwards course into oral cavity

Question 19

larynx role in effort closure - how does it work

Answer 19

Vocal & vestibular folds are adducted (closed)
Rima glottidis is closed
Vestibule is also closed

Question 20

what is the effect of pathologies or trauma to the frontal lobe if there is movement of olfactory bulb?

Answer 20

may tear the olfactory nerves causing anosmia
(loss of sense of smell)

Question 20

importance of the anterior & posterior ethmoidal arteries

Answer 20

These vessels form many anastomoses, especially in the anterior septal region & this is an area in which nosebleeds can commonly occur

Question 21

which sinus is more prone to chronic infections and why?

Answer 21

-Maxillary sinus
-prone to chronic infections because fluid can accumulate as the drainage is near the roof , so fluid falls to the floor and accumulates
(drainage is harder)

Question 22

dental importance to position of maxillary sinus

Answer 22

-Extraction of maxillary molar teeth might damage the maxillary sinus floor

-This could create an opening between the maxillary antrum & oral cavity (oro-antral communication) with the potential of causing infection

-As the innervation maxillary teeth and the mucous membrane of the maxillary sinuses is the same (superior alveolar nerves), toothache sensation may also occur in this scenario

Question 23

what could occur due to tumour on the pituitary gland ?

Answer 23

If there is tumour or abnormality on the pituitary gland then it can compress the optic chiasm and will lead to visual pathology known as tunnel vision (where cannot see from sides of visual field)

Question 24

what can cause the central retinal artery to become occluded and what occurs ?

Answer 24

transient causes such as amaurosis fugax that leads to painless temporary loss of vision in the affected eye

Question 25

what will a rise in ICP cause?

Answer 25

Raised intracranial pressure is transmitted to the meninges & subarachnoid space around the optic nerve (CN II) that slows retinal venous drainage via the central retinal vein causing papilloedema (build up of fluid in the subarachnoid space)

Question 26

what is Preseptal cellulitis

Answer 26

Infection of the skin/subcutaneous tissue (superficial layers) anterior to the orbital septum

Question 27

what is orbital cellulitis

Answer 27

-Infection posterior to the orbital septum
-Pain on movements of the eye that are restricted along with proptosis (bulging of the eye)
-Threatens vision & there is risk of infection spread to cavernous sinus or meninges/brain

Question 28

what is conjunctivitis

Answer 28

Inflammation of the membrane covering the posterior surface of the eyelid & eyeball

Question 29

what would occur is there is damage to occulomotor nerve

Answer 29

• the superior oblique & lateral rectus are unopposed
  -eye will be turned downwards and outwards and upper eyelid will be drooping (ptosis)

Question 30

Aneurysms of posterior cerebral, superior cerebellar arteries and posterior communicating artery would do what ?

Answer 30

compress occulomotor nerve as it passes closely by these nerves

Question 31

damage to the tympanic membrane will cause what

Answer 31

damage to the chorda tympani nerve which will affect sensation taste at the anterior 2/3rd of tongue