Subjective Visual Complaints Flashcards
what are positive visual phenomena?
patients see “things” due to disease of the orbit, optic nerve and/or brain
they can be illusions or hallucinations
what is an illusion?
an abnormal perception of real objects
what is a hallucination?
a visual sensation that does not correspond to a real object
simple = flashing lights
complex = image of a person
what are some positive visual phenomena due to eye disease?
halos around lights, metamorphopsia (illusion) and flashes (simple hallucination)
what positive visual phenomena are seen in optic nerve disease?
simple hallucinations = flashes/sparkles (compressive, optic neuritis, NAION, AION)
what can cause an illusion in the brain?
a tumor or stroke
what can cause a hallucination in the brain?
migraine (simple - most common), brain tumor, metabolic disease, dementia (complex)
what are some causes of simple metamorphopsia illusions?
macular disease or corneal disease (disappears when covering one eye)
what are some causes of complex metamorphopsia illusions?
parietal tumor/stroke, parietal seizures, migraine (persists when covering one eye)
what are the 3 types of complex illusions that can cause diplopia?
polyopia, palinopsia, and akinetopsia
what is polyopia? what causes it?
moving objects leave multiple still images or a blurred trail
parieto-occipital tumor/stroke
what is palinopsia? what causes it?
persistent visualization of an object after stimulus has been removed
parieto-occipital tumor/stroke or drug abuse
what is akinetopsia? what causes it?
smoothly moving objects look stationary or jump from place to place (motion blindness)
bilateral occipito-temporal lobe tumor/stroke
what can cause a simple hallucination?
retinal disease (PVD, RD, tear), optic nerve disease, migraine
what can cause a complex hallucination?
dementia, metabolic disease, illegal drug use, occipital tumor/stroke, occipital epilepsy, Charles Bonnet syndrome
what are negative visual phenomena?
dimming or loss of vision
due to disease of orbit, optic nerve, cerebral vascular supply, neck and heart
what are causes of monocular negative visual phenomena?
CRAO, CRVO, retinal vasospasm (ocular migraine), GCA, papilledema (IIH), amaurosis fugax (most common) and calcium emboli
what are causes of binocular negative visual phenomena?
migraine (most common), papilledema (IIH), verebrobasilar insufficiency and postural hypotension
what is amaurosis fugax?
sudden onset of severe vision loss in one eye, painless, lasts for seconds - minutes and completely resolves in 10 minutes
fellow eye is unaffected and no other neurological symptoms
who typically gets amaurosis fugax?
50+ year olds with cardiovascular risk factors
what are the examination findings for amaurosis fugax?
normal ocular exam in both eyes, normal perimetry and pupils
may see a Hollenhorst plaque in retinal arteriole
what causes amaurosis fugax?
ICA stenosis, ICA dissecting aneurysm (will have miosis), GCA, or cardiac valvular disease (younger patients)
what is the work-up needed for amaurosis fugax patients?
blood-work = CBC with diff, ESR, CRP and check for clots
carotid artery doppler
MRI/MRA
echocardiogram
what is ocular ischemic syndrome and what can cause it?
entire eye suffers from hypoperfusion (ophthalmic artery)
severe ICA stenosis or occlusion
GCA
