Opth- neuro-opthalmic disease Flashcards
what is diplopia
double vision
what is esotropia
squint or ‘cross eyed’ where one or both eyes turn inwards towards the nose
what is exotropia
one or both eyes turn outwards
what is hypertropia
one of eyes looks upwards
what is hypotropia
one of eye looks downwards
horizontal double vision is associated with problems with which muscles of the eye
lateral rectus
medial rectus
vertical double vision is associated with problems with which muscles of the eye
superior oblique
inferior oblique
super rectus
inferior rectus
which muscle of the eye would be affected by a cranial nerve IV palsy (trochlear nerve)
superior oblique muscle
which muscles of the eye would be affected by a cranial nerve III palsy (oculomotor nerve)
superior rectus
medial rectus
inferior rectus
inferior oblique
which muscle of the eye would be affected by a cranial nerve VI palsy (adjacent)
lateral rectus muscle
CN III supplies all extra ocular muscles except which two-
lateral rectus
superior oblique
causes of CN III (oculomotor) palsy
microvascular
tumour
aneurysm !!!
MS
congenital
‘down and out’ appearance of eye suggests which CN palsy
CN III (oculomotor)
what is ptosis
upper eyelid dropps over eye
what is miosis
small or constricted pupils
what does a painful CN III palsy indicate
aneurysm
causes of CN IV palsy
congenital decompensated !!!
microvascular
tumour
blunt head trauma can result in bilateral CN IV palsy!!!
which nerve palsy results in affected eye turned upwards in primary position
CN IV
which compensatory head position is seen in patients with bilateral CN IV palsy
chin down head posture
which compensatory head position is seen in patients with unilateral CN IV palsy
contralateral head tilt
causes of CN VI nerve palsy
microvascular
raised intracranial pressure!!!
tumour
congenital
CN VI palsy results in which eye fault
squint- eye turned inward
what is optic neuritis
inflammatory optic neuropathy usually affecting one eye at a time and typically presents with acute or subacute vision loss
typical optic neuritis is strongly associated with what?
MS
atypical causes of optic neuritis
antibody-mediated
non-infectious- neurosarcoidosis and systemic autoimmune conditions such as SLE
infectious- syphilis, Lyme disease, cat-scratch disease, herpes zoster, sinus disease
post-infectious
symptoms of optic neuritis
acute/subacute unilateral vision loss
retrobulbar and peri-ocular pain
photopsias (flashes) exacerbated by eye movements
reduced colour vision
most likely cause of CN III palsy
posterior communicating artery aneurysm
most important investigation for optic neuritis
MRI
what is internuclear ophthalmoplegia
disorder of conjugate lateral gaze in which the affected eye shows impairment of adduction
in younger patients, what is a common cause of internuclear opthalmoplegia
MS
in older patients, what is a common cause of internuclear ophthalmoplegia
vascular aetiology- stroke
what vision loss occurs from a lesion of the left optic nerve
complete blindness of left eye
what vision loss occurs from a lesion of the optic chiasm
bitemporal hemianopia- loss of outer (temporal) visual fields in both eyes
what vision loss occurs from a lesion of the left optic tract
right homonymous hemianopia- loss of right visual fields of both eyes
lesions before the optic chiasm affect one/two eyes?
one eye
what vision loss defects occurs from lesions after the optic chiasm
homonymous defects (same side of both eyes)
causes of optic nerve defects
ischaemic optic neuropathy
optic neuritis- commonly MS
tumours (rare)
optic nerve field defect-
unilateral vision loss
complication of optic nerve defects
optic atrophy
most common cause of optic chiasm defects
pituitary tumour
causes of ischaemic optic neuropathy
giant cell arteritis
non-arteritis ION
clinical features of ischaemic optic neuropathy
sudden usually painless vision loss
signs of ischaemic optic neuropathy associated with GCA
headache
scalp tenderness
enlarged temporal arteries
how does ischaemic optic neuropathy appear on fundoscopy
pale, swollen disc
what is papilloedema
swelling of the optic nerve due to increased intracranial pressure
intracranial pressure is the sum of what-
brain, blood, CFS
what is optic atrophy
optic nerve shrinkage caused by degeneration of retinal ganglion cell axons
acquired causes of optic atrophy
MS
papilloedema (longstanding)
raised intracranial pressure (glaucoma, tumour)
retinal damage
ischaemia
toxins
nutritional deficiencies
clinical signs of optic atrophy
reduced visual acuity
reduced contrast sensitivity
RAPD
