Blue 2-3 Flashcards
(17 cards)
What is Benedikt syndrome
3rd palsy + contralateral intention tremor
Red nucleus / paramedian midbrain
BIT CA NIA WCH
CANIA BITWCH
Claude syndrome
3rd palsy
Contralateral ataxia
Midbrain
Nothnagel syndrome
3rd palsy
Ipsilateral ataxia
Superior cerebellar peduncle
Weber syndrome
3rd palsy
Contralateral hemiparesis
cerebral peduncle
What is see-saw nystagmus
When is it seen
Disconjugate, torsional nystagmus - one eye rises and intorts while other eye falls and extorts
Then reverse in next cycle
Caused by parasellar masses - pirtuiatry tumour, craniopharyngiomae, brainstem stroke, trauma, MS
What does right side non dominant parietal lobe infarction cause
Left side visual neglect
Inferior quadrantanopia
What does left side dominant parietal lobe infaction cause
Gerstmann syndrome
Left/right disorientation
Finger agnosia
Dysgraphia (inabilaity to write)
duscalculia - inability to calculate
What factors reduce risk of MS in ON
Male sex
Optic disc swelling
Atypical optic neuritis features -
- absent pain
- NPL vision
- severe disc swelling with haemorrahge
What is superior oblique myokymia?
Unilateral, low amplitude (<4 degrees), high frequency (>50Hz) torsional nystagmoid movement of SO muscle.
Triggered by fatigue, stress, caffiene
Some imporvement with topical beta blcokers, carbemazepine, phenytoin, baclofen, gabapentin, memantine, botox
MAy be linked with neurovascular compression of 4th nerve
What is an NAAION disc at risk?
cup to disc ratio is small and disc appears crowded and hyperaemic
What feature suggests an ischaemic third nerve palsy
signs of recovery within 3 months
What does aberrant regeneration in 3rd nerve palsy such as upper lid retraction and pupil constriction on eye movement suggest?
Sign of compression from slow growing tumour such as meningioma in cavernous sinus or aneurysm.
What does pupil sparing with single muscle weakness indicate in 3rd nerve palsy
Partial third - may be compressive lesion
MRA/CTA
Describe visual loss in LHON
Painless
One eye then next within few weeks/months
Severe to 6/60 or HM
CEntral / centrocaecal scotoma
What are ddx for bilateral sequential optic nerutopathy?
AION
Demyelination
NMO
LHON
What test for ocular myasthenia?
Ice pack test
Ice applied to drooped lid for 2-5 minutes and pre/post ice measurements of lid are taken
Positive result if eyelid opens by 2mm or more
Ice cools skeletal muscle tissue cooling activity of AChE enzyme
(edrophonium used in tensilon test)
What is used to assess tonic pupil. What is Holmes Adie syndrome
Dilute pilocarpine 0.1%
Iris sphincter is highly senstive to ACh
Abnomral pupil constricts in response to weak stimulation
Aberrant regeneration may develop over time increasing supply to iris sphincter resulting in constricted pupil
Adie syndrome - pupil changes with lost/absent deep tendon reflexes
