Term
What single test has the highest specificity and best precision for diagnosing glaucoma? |
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Definition
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Term
Can NFL loss occur before evidence of VF loss? |
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Definition
yes, which is why ONH is important |
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Term
What are the 4 main ways to measure ONH disc size? |
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Definition
Planimetry
scanning laser tomography
Contact lens (central 3 mirror gonio)
High plus |
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Term
What are the correction factors for contact lenses and high plus lenses? |
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Definition
1.27 for contact
HP lens depends on power/brand |
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Term
What is the equation for calculating ONH area? |
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Definition
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Term
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Definition
a localized irregularity in the radius of the optic cup,red flag for glaucoma |
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Term
Where is ONH thinning most common to occur first? |
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Definition
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Term
How does the central retinal artery (CRA) induce notching? |
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Definition
The CRA trunk is more commonly nasal-superior and notching tends to occur opposite in the inferior-temporal area |
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Term
Why does nerve fiber loss due to glaucoma require a evaluation rim to disk and not just cup to disc ratios? |
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Definition
If an ONH is elliptical, then changes in C/D vertically vs horizontally will be different and more difficult to determine expressed as a percentage of the cup, while if it is expressed as a percentage of rim tissue, any changes will be more apparent |
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Term
When determining rim to disk and cup to disk ratios, what is the primary mathematical principle to keep in mind? |
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Definition
Both the vertical and horizontal proportions should add up to '1.0' |
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Term
When does the C/D horizontal vs vertical proportion indicate glaucoma concern? |
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Definition
Horizontal C/D divided by Vertical C/D should be greater >1 with a typical value of 1.15-1.19 |
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Term
Is diffuse arteriole narrowing pathognomonic for glaucoma? |
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Definition
No, though it can occur in glaucoma, it can occur in many other types of ONH damage |
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Term
What is indicated by shifting locations of vessels over time? |
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Definition
Usually a sign of more severe damage in glaucoma. A senstive way to discern ONH damage secondary to glaucoma. |
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Term
What is 'bayoneting' of ONH blood vessels? |
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Definition
It comes to a very fine point due to the BV dropping off into the cup. However, it is not a reliable indicator of glaucoma. |
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Term
What is a splinter hemorrhage? |
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Definition
Another name for Drance hemorrhage, common (but not limited to) glaucoma damage. |
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Term
What are common causes of splinter hemorrhages? |
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Definition
Glaucoma
PVD
Resolving BRVO
Diabetic Retinopathy |
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Term
Regardless of cause, what does an optic disc hemorrhage indicate? |
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Definition
Tx is necessary, so determine the active pathology |
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Term
How long does an optic disc hemorrhage take to resolve? |
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Definition
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Term
In an advanced glaucoma patient, what do optic disk hemorrhages signify? |
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Definition
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Term
What is peripapillary pigmentary atrophy? |
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Definition
mottled appearance to RPE seen around the disc |
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Term
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Definition
central zone of RPE and choriocapillaris atrophy leading to visibility of choroidal vessels and sclera |
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Term
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Definition
peripheral zone RPE atrophy surrounding the ONH |
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Term
How does alpha atrophy compare to a choroidal crescent? |
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Definition
alpha atrophy is more mottled and less uniform, irregular borders |
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Term
What is the suspected etiology of peripapillary pigment changes? |
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Definition
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Term
Where is peripapillary pigmentary atrophy typically found? |
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Definition
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Term
Is alpha atrophy present in normal eyes? |
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Definition
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Term
Is beta atrophy present in normal eyes? |
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Definition
not commonly. Usually pathologic. |
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Term
What is the progression of peripapillary pigmentary atrophy? |
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Definition
Patches typically start as alpha and progresses to beta over time if pathologic mechanism is not intervened |
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Term
What does peripapillary pigment atrophy usually indicate is happening in the eye? |
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Definition
advanced damage, often associated with rim loss in the same sector |
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Term
What is an acquired pit of the ONH? |
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Definition
sharp localized depression of lamina cribrosa |
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Term
What color is typically seen around acquired pts of the ONH? |
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Definition
Usually found in pallorous ares of ONH |
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Term
What is the most likely location of acquired pits of the ONH? |
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Definition
inferior temporal quadrant (opposite of CRA trunk?) |
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Term
What pathology are acquired pits of the ONH most commonly found in? |
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Definition
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