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47 Cards in this Set
- Front
- Back
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What kinds of cells surround the optic nerve?
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Oligodendrocytes!!!
It's a part of the CNS! |
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What is more nasal, the optic disc or the fovea?
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The disc
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What structure is in the middle of the "arc" of the retina?
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The fovea
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What does the fovea look like in the eye?
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A little red spot
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What are some causes of centra, cecocentro cecomas?
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Damage to the small foveal fibers
Toxic, metabolic, and nutritional problems |
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What kinds of conditions can cause a "scimtar" defect on a visual field?
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Glaucoma
Ischemia of the optic nerve |
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What are causes of a hemanopic defect?
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Defects at the chiasm
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What is a cause of pallor of the optic disc?
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LOSS OF AXONS:
-Glial overgrowth -Blood supply problems |
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What is a cause of excavation to the optic disc? What do you look for here?
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GLAUCOMA!
The rim occupies a much smaller area than it should...the cup diameter is more than half that of the disc |
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What is a cause of elevation of the optic disc?
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Increased ICP
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What is a cause of hypoplasia of the optic disc?
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Congenital problems with the optic nerve; it doesn't fully develop
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What are some common disorders of the optic nerve?
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Optic neuritis
Ischemic optic neuropathy Compression by a mass Infiltration by cancer Systemic Toxic-nutritional-metabolic disorders Increased ICP Glaucoma |
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What is the presentation of someone with optic neuritis?
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Subacute, monocular vision loss
Pain around the eyes |
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Who gets optic neuritis?
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Ages 15-45
Women > men |
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What are causes of optic neuritis?
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MS
Autoimmune causes Infections |
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What are signs of optic neuritis?
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afferent pupillary defect
Reduced visual acuity Nerve bundle defect Optic disc normal, swollen |
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What are the two types of ischemic optic neuropathy? Which is more common? Which is more serious?
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Arteritic: more serious
Non-arteritic: more common |
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What kind of people get giant cell arteritis?
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>70 YO
Both sexes equally |
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What are the systemic symptoms of giant cell arteritis?
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Premonitary aches
Malais JAW CLAUDICATION Anorexia Poor appetite Anemia |
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What are the ophthalmic manifestations of giant cell arteritis?
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Sudden, severe visual loss...either unilateral or bilateral
APD |
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What is the treatment for giant cell arteritis?
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High dose steroids
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What labs are used to indicate giant cell arteritis? What's the definitive test?
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Elevated sed rate, CRP
Biopsy for diagnosis |
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What's the prognosis for giant cell arteritis?
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No visual recovery.
:( |
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What kinds of people get non-arteritic ischemic optic neuropathy?
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>40
Equal gender predilection |
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What are risk factors for non-arteritic ischemic optic neuropathy?
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DM
HTN Smoking |
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How does someone present with non-arteritic ischemic optic neuropathy?
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Sudden painless monocular loss of vision
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What are the signs of non-arteritic ischemic optic neuropathy?
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A segmentally swollen optic disc
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What's the prognosis for non-arteritic ischemic optic neuropathy?
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Non-progressive, but you don't recover
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How does someone present with compression of the optic nerve by a mass?
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Sudden or slow vision loss with or without pain
Basically, any way that you can present with vision problems. |
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Where do masses normally compress the visual system? What type of field defect normally results?
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Intracranially at the chiasm
Hemianopic field defect |
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What types of tumors normally compress the visual system?
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PItuitary adenoma
Meningioma Pliocytic astrocytoma Craniopharyngioma Aneurysm Germ cell tumor Cyst MOST ARE BENIGN! |
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How does someone present if their optic nerve has been infiltrated by cancer?
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Subacute, severe vision loss
They have a history of cancer |
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Other than cancer, what can invade the optic nerve?
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Sarcoidosis
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What are some tests that you can order if you suspect that the optic nerve has been invaded by cancer?
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MRI: meningial enhancement
LP: pleocytosis, high protein |
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How do systemic-toxic-nutriotional-metabolic diseases impact vision?
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Slowly, progressive, SYMMETRICAL
Central, centrocecal scotomas |
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What are some different substances that can cause optic nerve defects?
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Ethambutol
Methanol Alcohol VERY POOR DIET |
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What is a metabolic condition that can cause optic nerve problems?
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Mitochondrial dysfunction: leber hereditary optic neuropathy
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What is papilledema?
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Optic disc edema secondary to increased ICP
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What are some causes of papilledema?
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Trauma
Decreased reabsorption by arachnoid granulations Decreased outflow by CSF Edema Mass |
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What is the treatment for papilledema?
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Relieve the cause
Shunt! |
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What are the four types of glaucoma?
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Primary open angle
Secondary Angle closure Congenital |
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What happens in primary open angle glaucoma?
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No real reason; it just happens
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What is the cause of angle closure glaucoma?
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The outflow tract through the canal of schlemm is blocked by the iris
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What is the most common kind of glaucoma?
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Primary open angle glaucoma
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How does primary open angle glaucoma present?
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Slowly progressive arcuate nerve fiber bundle defects
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What are the kind of people who get primary open angle glaucoma?
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> 40
Equal gender |
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What's the treatment for primary open angle glaucoma?
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Lower intraocular pressure!
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