Eye Flashcards
What this?
CN 3 - oculomotor nerve palsy
“Down and out” can’t adduct
What’s this? What could cause?
CN3- occulomotor nerve palsy
Down and out
Eye dilated, ptosis, can’t adduct
Causes:
Congenital
Trauma
Mass/ tumour
Demyelination - GBS, MS, neuromyelitis optica spectrum disorders
Vascular e.g. posterior cerebral aneurysm
Hydrochephalus
- Arnold Chiari?
- Mass
What this?
Causes?
CN 6 - abducens nerve palsy
“In and stuck”
Can’t abduct
Causes:
Congenital
Trauma
Mass/ tumour
Demyelination - GBS, MS, neuromyelitis optica spectrum disorders
Vascular e.g. posterior cerebral aneurysm
Hydrochephalus
- Arnold Chiari?
- Mass
Infection: VZV
Eye exam Invx
Ophthal rv
MRI-B: neoplasm, inflam (eg. GBS), stroke, raised ICP
MR-A: AVM (binasal or bitemporal heminaopia)
Infection: FBC, CRP, VZV PCR, CMV serology
Craniopharyngioma or pituitary adenoma (binasal or bitemporal heminaopia):
- IGF-1, ACTH (dex suppression test), prolactin, LH/FSH, TSH
Optic nerve glioma (NF-1*):
- other signs NF1: 1st degree relative, axillary or inguinal freckling, lisch nodule, XR: distinctive osseous lesions (thinning long bone)
What’s this?
Lisch nodules - NF1
What’s this? Causes?
No red reflex = leukokoria
Retinoblastoma
Cataracts
Glaucoma (ON damage)
Causes of cataract
Idiopathic
TORCH - toxoplasmosis, CMV, rubella, HSV
Trauma
RTx
Syndromes:
- smith-lemli- opitz: cannot make cholesterol, FTT, microceph, ID, syndactyly
- bardet-biedl
Aneuplodies: T21, Turner
Location of CNS lesion
- vertical nystagmus
Cerebellar
Location of CNS lesion
- horizontal nystagmus
Can also be caused by?
Brainstem
Anticonvulsant medications (phenytoin, carbemazepine, lamotrigine, valproate)
What’s this?
Exotropia
Causes of horizontal strabismus (outside of CN palsies)
Accommodative
Congenital
Duane syndrome - eye movement disorder characterised by failure of CN6 to develop normally
Exotropia: looks out
Esotropia: looks in
Retinal causes of RAPD
Retinal detachment
Ischemic retinal disease
Intraocular tumour: melanoma, metastatic RB
Infection: CMV, HSV
Name visual field defect and causes
Complete lesion of optic nerve
- compressive tumour (optic nerve glioma in NF1)
- trauma
- inflammatory: optic neuritis
- IIH
- vasculitis
- anterior ischemic retinopathy
Name visual field defect and causes
Quadrantinopia
Involvement of optic radiations
Lesion in contra lateral occipital lobe
Name visual field defect and causes
Bitemporal hemianopia
Lesion impinging on optic chiasm
- pituitary adenoma
- craniopharyngioma
- anterior communicating artery aneurysm (rare)
Name visual field defect and causes
Homonymous hemianopia
Pressure or lesion on one (left in this example) optic tract
- neoplasm
- AVM
- infection (e.g. encephalitis)
- ischaemia
Name visual field defect and causes
Nasal hemianopia
Lesion involving perichiasmal area
- tumour
- stroke
