1/81
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
ischemia = e.g. ischemic optic neuropathy
compression = e.g. a tumor pushing on the chiasm
inflam = e.g. demyelinating disease
trauma = e.g. traumatic optic neuropathy after getting hit in the eye
What are 4 potential causes of non-glaucomatous ON cupping?
no = rim pallor is most likely neuro disease
Is cupping of the ONH glaucoma if the ONH rim is pale?
yes = rim thinning is glaucoma
Is cupping of the ONH glaucoma if the ONH rim is gone/thin?
yes = BV bayonetting
Is cupping of the ONH glaucoma if the ONH rim is sharpened?
ONH hypoplasia
myopia
aphakia
optic atrophy
infants
What are some causes of a pale ONH?
pale nerve head
reduced VA
APD
dyschromatopsia
VF defect
RNFL dropout
electrodiagnostic dropout
What 3 findings will we always see in true optic atrophy?
hypoplastic ONH = part of sclera is filling optic canal around the ONH
What is the cause of this pale ONH?
reddish
Through NS CATs, a pale ONH may look ___________.
pink
Through dim illumination or an undilated pupil, a pale ONH may look __________, which is why it's important to assess the ONH on bright illumination.
AKA secondary optic atrophy = lesion in the gangiion cells or ONH or due to RP = BLURRY disc margins, artery attenuation or absence, sheathed BV
What is ascending optic atrophy?
papillitis
chronic papilledema
periarteritis
CRAO
AAION
POAG
What are some causes of ascending optic atrophy?
AAION
What cause of ascending optic atrophy is shown here?
RP
What cause of ascending optic atrophy is shown here?
chronic atrophic papilledema
What cause of ascending optic atrophy is shown here?
AKA primary optic atrophy = lesion in the LGN to the ONH = SHARP disc margins, normal BV
What is descending optic atrophy?
retrobulbar optic neuritis
toxic neuropathy
trauma
neoplasms in the orbit, canal, cranium (compression
What are some causes of descending optic atrophy?
neoplasm in cranium (craniopharyngioma) causing compression
What cause of descending optic atrophy is seen here?
intracranial injury to ON
What cause of descending optic atrophy is seen here?
difficult to ascertain cause = could be due to CRAO, canalicular meningioma, hypotensive events, etc.
What is the challenge with diffuse ONH pallor?
toxic disease = alcohol, malnutrition
hereditary degeneration = Leber's optic atrophy, autosomal dominant optic atrophy, etc.
acute demyelinating disease
compressive disease
What typically causes temporal segmental ONH pallor?
papillomacular bundle is involved = cecocentral VF defect from blindspot to fixation
What retinal and VF area is associated with temporal segmental ONH pallor?
glaucoma
What typically causes inferior wedge-shaped segmental ONH pallor?
ischemic optic neuropathy
What typically causes superior wedge-shaped segmental ONH pallor?
optic tract lesions = carry ipsilateral temporal fibers and contralateral nasal fibers
optic chaism lesions = bilateral bow tiee
What typically causes "bow tie" segmental ONH pallor?
fibers from temporal retina entering OS ONH
fibers from nasal retina entering OD ONH
papillomacular bundles of the OD ONH
Ex) if you lesion the left optic tract, which retinal fibers are affected?
bow tie pallor in OD ONH
temporal pallor in OS ONH
Ex) if you lesion the left optic tract, which ONH areas are affected?
NAAION or AAION = ischemic event like a local infarction of the post ciliary arteries
What typically causes altitudinal segmental ONH pallor?
acquired optociliary shunt BV on a pale ONH with slow progression vision loss
What is the Hoyt-Spencer sign?
sphenoid wing meningiomas
ON gliomas
ON arachnoid cysts
chronic OAG
ON drusen
CRAO
chronic papilledema
DM
What are some possible causes of acquired optociliary shunt BV?
glial veil
What finding shown here is a cause of pseudo disc edema?
myelinated nerve fibers
What finding shown here is a cause of pseudo disc edema?
CWS near the ONH
What finding shown here is a cause of pseudo disc edema?
flame-shaped hemorrhages near the ONH with CWS
What finding shown here is a cause of pseudo disc edema?
drusen of the ONH
What finding shown here is a cause of pseudo disc edema?
giant hamartoma of the ONH
What finding shown here is a cause of pseudo disc edema?
hypoplastic ONH – vessels seem out of proportion to the size of the ONH
What finding shown here is a cause of pseudo disc edema?
papilledema due to IIH
NOTE: papilledema is just 1 cause of disc edema
What finding shown here is a cause of true disc edema?
papillitis with disc edema and good vision
What finding shown here is a cause of true disc edema?
idiopathic scarring of ONH
What finding shown here is a cause of true disc edema?
BRVO = venous stasis retinopathy with edema, hemes
What finding shown here is a cause of true disc edema?
grade 4 HTN retinopathy causing disc edema
What finding shown here is a cause of true disc edema?
AAION causing disc edema, flame hemes
What finding shown here is a cause of true disc edema?
mineralized hamartoma, closely related to ON astrocytic hamartoma, often found in tuberous sclerosis pt's
What is a giant hamartoma of the ONH?
hyaline, acellular, calcium phosphate byproducts of disc astrocytes (may or may not be calcified)
What are disc drusen?
papilledema = present
drusen = absent
How can we differentiate papilledema from drusen based on the cup?
papilledema = blurred sup and inf
drusen = symmetric, scalloped blur
How can we differentiate papilledema from drusen based on the disc margins?
papilledema = hyperemic
drusen = normal
How can we differentiate papilledema from drusen based on the colour?
papilledema = elevated rim that extends into RNFL
drusen = central elevation, bumpy
How can we differentiate papilledema from drusen based on the NRR?
papilledema = edema sup and inf, muddy peripapillary reflex
drusen = focal atrophy, normal linear light reflexes
How can we differentiate papilledema from drusen based on the RNFL?
papilledema = optociliary shunts develop, venous dilation, absent SVP
drusen = central origin, trifurcation and other anomalous patterns, present SVP
How can we differentiate papilledema from drusen based on the BV?
elevated ICP > 200mmH2O
NOTE: pt may not have had an SVP to begin with, so this isn't always the best rule of thumb!
Why MIGHT there no SVP in disc edema?
retroilluminate the ONH by putting the beam right beside it
red-free filter
How can we better visualize disc drusen on fundoscopy?
true
True or False: drusen of the ONH are the most common congenital/inherited optic neuropathy.
hyperAF drusen within the hypoAF nerve head
How do disc drusen appear on FAF?
papilledema = rounded, regular elevation +/- lazy V sign
drusen = irregular elevation
How can we differentiate papilledema from drusen with OCT?
hyper-reflective if calcified
How do disc drusen appear on B scan?
hyper-reflective if calcified
How do disc drusen appear on a CT scan?
buried drusen may migrate to the surface of the ONH
How can drusen progress anatomically over time?
VF defects may develop, including an enlarged blindspot and arcuate defect
How can drusen progress functionally over time?
false
True or False: drusen and papilledema will not coexist at the same time in a pt.
blockage
How do surface drusen appear on early IVFA?
nodular staining
How do surface drusen appear on late IVFA?
no staining or nodular staining
How do buried drusen appear on early IVFA?
late peripapillary staining (noduler, circumferential)
How do buried drusen appear on late IVFA?
early and late diffuse leakage
How does disc edema appear on IVFA?
early = edema leaks, drusen stain
late = edema leaks, drusen stain
How does co-existent drusen and edema appear on IVFA?
double ring sign = outer yellow sclera, inner pigmented ring around ONH
margins may be blurred due to too many crowded axons
NOTE: these findings are not that common
What are 2 features of the disc margin that suggests it may be a hypoplastic ONH?
overestimating
Double ring sign may result in you _______________________ the nerve size.
subnormal axons
normal mesodermal glial elements
A hypoplastic disc actually has a subnormal number of _________, but it has a normal number of ____________________________________________.
RNFL is often thin/absent due to either axon atrophy or RGCs failing to develop
What feature of the NRR and RNFL suggests it may be a hypoplastic ONH?
pale colour bc the sclera is showing through
red colour bc the small disc is in high contrast to the surround
What feature of the disc colour suggests it may be a hypoplastic ONH?
tortuous, large in comparison to the nerve itself
What feature of the disc colour suggests it may be a hypoplastic ONH?
yes
Can VF defects result from hypoplastic ONH?
most often as bitemporal hemianopsias but can be other defects anywhere in the VF, including binasal or ST defects
What is the most common VF defect we see in hypoplastic ONH?
true
True or False: hypoplastic discs may cause a VF defect that does NOT respect the vertical midline.
developmental abnormalities like GH deficiency, hypothyroidism
forebrain anomalies such as lacking a septum pelucidum between the 2 lateral ventricle halves
What are some associations seen in pt's with bilateral hypoplasia of their ONH and poor VA?
refer to pediatrician to assess:
GH levels
thyroid function
endocrine function
CT/MRI to look for basal encephalocoele = abnormal communication of bone that allows brain tissue to herniate into orbit, nasal pharynx, etc
How should we manage pt's with bilateral hypoplasia of their ONH and poor VA?
no management necessary other than routine following with an OD/OMD and pediatrician to monitor for endocrine issues
How do we manage pt's with bilateral hypoplasia of their ONH and good VA?
no management necessary other than routine following with an OD/OMD and pediatrician to monitor for endocrine/neuro issues
How do we manage pt's with unilateral hypoplasia of their ONH and good OR poor VA?
septo-optic dysplasia with...
bilateral ONH dyplasia
absence of septum pellucidum
agenesis of corpus callosum
dysplasia of 3rd ventricle
hypopitutitarism
What is De Morsier's syndrome?
ON aplasia/dysplasia
ONH pit
sup segmental hypoplasia
ONH coloboma
What are 4 other congenital nerve disorders than may be associated with forebrain anomalies?
hypoplastic ONH
anosmia
forebrain anomalies
gonadotropin deficiency = delayed puberty, amenorrhea
What is Kallman's syndrome?