Neuro-Ophthalmology Flashcards
Describe the visual pathway from the retina to the occipital cortex
Retina –> optic nerve –> optic chiasm (temporal tracts cross over) –> optic tract –> synapse at lateral geniculate nucleus –> optic radiations –> occipital/visual cortex
Which visual field defect will result from an interruption of the visual pathway at the optic nerve?
Unilateral visual loss (same side)
Which visual field defect will result from an interruption of the visual pathway at the optic chiasm?
Bitemporal hemianopia
Which visual field defect will result from an interruption of the visual pathway at the optic tract?
Homonymous hemianopia (opposite side)
Which visual field defect will result from an interruption of the visual pathway at the optic radiation in the temporal lobe?
Homonymous upper quadrantanopia (opposite side)
Which visual field defect will result from an interruption of the visual pathway at the optic radiation in the parietal lobe?
Homonymous lower quandrantanopia (opposite side)
Which visual field defect will result from an interruption of the visual pathway at the occipital cortex?
Homonymous hemianopia with macular sparing
What is RAPD and what is it testing?
Relative afferent pupillary defect (swinging light test)
- test of optic nerve function or global retinal function (not affected in macular disease)
What is Horner’s syndrome?
Loss of sympathetic supply to the eye
What are the features of Horner’s syndrome?
Ptosis
Miosis (contracted pupil, does not dilate)
Anhydrosis (ipsilateral reduced sweating)
What are some causes of Horner’s syndrome?
Pancoast lung tumour Carotid/aortic aneurysm Lesion of the neck Congenital Idiopathic
What should be rules out if a patient has a painful Horner’s syndrome?
Carotid dissection
What will the primary symptom be if there is a lesion on cranial nerve III, IV or VI?
Double vision
What are the features of a oculomotor palsy?
Ptosis
Down + out ocular position
What are the causes of an oculomotor palsy?
Microvascular
Trauma
Aneurysm
