The eye in neurological conditions Flashcards
What will eye movement defects cause?
Double vision
What will visual defects cause?
Problems with visual acuity and field loss
What can cause neurological eye problems?
Vascular disease Turmous (primary and secondary) Trauma Demyelination Inflammation/ infection: sarcoidosis, neuroinflammatory, meningitis, encephalitis Congenital abnormalities
What ocular motility defects can occur?
3rd nerve palsy 4th nerve palsy 6th nerve palsy Inter-nuclear Supra-nuclear
What will a 6th nerve palsy cause?
Lateral rectus palsy - lack of abduction
What commonly causes a 6th nerve palsy?
Microvascular
Raised ICP
Tumour
Congenital
Why is the 6th nerve susceptible to raised ICP?
Passes over the petrous tip and a slight rise in ICP will cause impingement
How will a raised ICP present in the fundus?
Swollen disc - papilloedema
What action does the superior oblique muscle have?
Test by looking down and in
Action is down and out
Intorsion, depression and weakly abduction
What can cause a 4th nerve palsy?
Congenital decompensated
Microvascular
Tumour
Bilateral - closed head trauma
What muscles does CN3 supply?
SR, MR, IR, IO, LPS, sphincter pupillae
Where will the eye sit in a 3rd nerve palsy?
Down and out
Ptosis
What commonly causes a 3rd nerve palsy?
Microvascular Tumour Aneurysm - posterior communicating artery MS Congenital
What inter-nucleus connects the 3rd and 6th CN to allow for left or right movement of the eye together?
Medial longitudinal fasciculus
Allows for coordinated movements of the eye to look to the left or right
How will INO present?
Nystagmus of abducted eye
Eye trying to adduct will go slowly or won’t manage
What can cause INO?
MS
Vascular - stroke
What is pathognomonic of MS?
Hyperintensity at the lateral ventricles showing plaques
Where can visual field defects occur?
Optic nerve Chiasm Optic tracts Optic radiations Cortex
What lobes will the superior and inferior visual field radiations travel through?
Superior - temporal
Inferior - parietal
What can cause problems to the visual field?
Vascular disease - CVA
Space occupying lesion - SOL
Demyelination (MS)
Trauma - inc surgical
What type of visual field loss will occur after the lateral geniculate bodies?
Superior or inferior quadrantonopia
What will be spared if there is a lesion at the occipital cortex?
Macular sparing
What pathologies can occur at the optic nerve?
Ischaemic optic neuropathy - stroke of optic nerve
Optic neuritis - MS
Tumours - meningioma, glioma, haemangioma
What visual field loss will optic nerve defects cause?
Abide the horizontal - only inferior or superior affected
Common in glaucoma
