OCB03-2007 Flashcards
How do you test C.I?
Strong smelling things (eg coffee) at the nose
What could cause bilateral anosmia?
Trauma
Parkinson’s disease
COVID-19
What is anosmia?
Partial or complete loss of sense of smell
What could cause unilateral anosmia?
Frontal lobe lesion
What is functional anosmia?
Only able to detect odours occasionally
How do you test the cranial nerves associated with the eyes?
Inspection of eyes, eyelids, iris and pupils for any cloudiness
Pupillary reactions
- light reflex with hand separation
- focusing on finger
Visual acuity with standardised Snellen chart and Ishihara test
Visual fields (peripheral vision)
Eye movement (following a finger)
Fundoscopy with ophthalmoscope
What is the Ishihara test used for?
Test for colour blindness/deficiency
What pupillary reactions are normal?
Light with hand separation should result in one pupil constricting
Focusing on a finger should result in equal constriction of both pupils
What is a direct pupillary reaction?
Reaction in the eye you are testing
What is a consensual pupillary reaction?
Reaction in the eye you are not testing
What structures should you see in a fundoscopy?
Optic cup
Optic disc
Fovea
Macula
Arteries and veins
What will you see in a fundoscopy of someone with papilloedema?
Swelling of optic disc
Margins of optic disc are not clear (blurred)
What is papilloedema often seen with?
Brain tumours
What will you see in a fundoscopy of someone with optic atrophy?
Paler and larger optic disc
How do you test eye movement?
Ask patient to follow finger with their eyes
Do not move head
Which cranial nerve controls eyelid elevation and what muscle is involved?
Oculomotor nerve (C.III)
Levator palpebrae superioris
What will you see in a patient with an oculomotor nerve palsy?
Pupil dilation in affected eye
Affected eye will look down and laterally at rest
What will you see in a patient with a trochlear nerve palsy?
Affected eye will look up and medially at rest
What will you see in a patient with an abducens nerve palsy?
Affected eye will not be able to look to the same side/laterally (abduct)
What is abducens nerve palsy often associated with?
Brain tumours
Increased intracranial pressure
What are the two rules of double vision?
Double vision is maximal in the direction of gaze of the affected muscle
The false image is the outer image that arises in the affected eye
What may cause single palsies of the cranial nerves controlling eye movement?
Medical = diabetes, atherosclerosis
Surgical = Tumour, aneurysm, trauma
What causes a single cranial nerve pathology?
Supranuclear lesion (CNS) or peripheral lesion
What causes multiple cranial nerve pathology?
CNS lesion of systemic diseases