Visual Fields
What is it called when you lose your vision in one eye?
Mononuclear field loss
What lobe is the visual cortex in?
Occipital lobe
Name two symptoms of issues at the optic chiasm?
Altered colour vision, loss of lateral field, blurred vision, difficulty with near tasks
What would a complete lesion of the optic nerve cause?
What should you do before checking visual fields?
Check visual acuity
What is it called when you lose your vision on one side of each eye?
Homonymous hemianopia
What part of the brain does the optic nerve originate and where does it travel to?
Midbrain to occipital lobe
What is a common cause of loss of lateral vision?
Pituitary tumour impacting the optic chiasma
What crainial nerve is the optic nerve?
CN II
Which nerve innervates the muscles of the eye?
CN III, CN IV and CN VI
What is it called when you lose your lateral vision in both eyes?
Bitemporal hemianopia
Does the brain have one or two visual cortexes?
Two, one on each side
After the chiasm the nerves travel via tracts. The left optic tract contains visual information from which parts of the eye?
Left lateral (temporal) and right medial (nasal) halves
Is double vision a symptom of optic nerve palsy?
No, it can be caused by CN III, CN IV and CN VI
Which cells in the eye detect light?
Rod cells
Why do patients have a smaller visual field in the bottom medial quadrant?
The nose is in the way
What is a common symptom of a lesion in the occipital lobe?
Visual hallucinations
Vision from which sides crosses over at the chiasm?
Medial
Which part of the eye does the optic eye attach to?
The retina, at the optic disc
Which cells in the eye detect colour?
Cone cells
What is it called where you lose a quarter of the vision in each eye?
Homonymous quadrantanopia
How many areas of the visual cortex are there?
Five (some sources say 6)
After the chiasm nerves travel via tracts. The left optic tract contains information from which parts of the eye?
The left lateral (temporal) and right medial (nasal) halves of the eyes
Which lobes of the cerebrum does the optic radiation pass through?
Temporal, parietal and occipital
Demonstrate how you would test the visual fields
if correct, double points