Neuro ILAs Flashcards
What is another name for Marcus Gunn pupil?
Relative afferent pupillary defect (RAPD)
What cranial nerve is responsible for pupil constriction?
Oculomotor (III)
What would be classed as normal vision using a Snellen chart? (6 metres)
6/6
What can the pinhole correction test indicate?
If not pinhole does not correct vision, this suggests the problem id not a refractive error (i.e. that that can be corrected with glasses) and is an organic visual disorder.
What is refractive error?
Inability of the cornea and lens to direct light rays into proper focus on the retina.
What are Cherry red spots?
Red spots seen in the eye on fundoscopy as the result of central artery occlusion
What is amaurosis fugax?
Temporary, painless loss of vision in one or both eyes - “a curtain coming down over the eye”
What causes amaurosis fugax?
Occlusion of central retinal artery (branch of ophthalmic artery) - can be caused by internal carotid stenosis/TIA.
What is anterior ischaemic optic neuropathy?
Loss of vision caused by insufficient blood supply to the optic nerve (posterior choroidal artery).
What is retinal detachment?
Retina becoming detached from the blood supply.
How can a gadolinium contrast MRI be used to investigate MS?
Can indicate the age of MS lesions - lesions that ‘light up’ indicate active inflammation and are usually less than 3 months old.
What investigations can be used to determine the cause of unilateral vision loss?
- History/examination
- Fundoscopy
- Fluorescein angiography
- MRI
What is the aetiology of optic neuritis?
Demyelination inflammation of the optic nerve.
Symptoms of optic neuritis.
Unilateral blurred vision, pain behind the orbit, worse when moving the eye. May be loss of colour vision. Worse in the shower, hot climate or when exercising.
Signs of optic neuritis.
Visual field loss, relative afferent pupillary reflex.
