Neuro Flashcards
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Name 2 Cause of 2nd order horner
- Apical lung ca
2. Thor ao aneurysm
4 Causes of 1st order horners
- Wallenberg syndrome
- Stroke
- Demyalinating disease of cervical spine
- Cervical disc dz
Name 3 causes of 3rd order horners
- Ica dissection
- Cav sinus thrombosis
- Cluster ha
Whats wallenberg syndrome?
Infarct of lateral medulla 2/2 pica stroke affects ipsilateral horners (1st order)
What male color blindness called
Deuteranomalous
What are the normal limits of a visual field?
60 degrees sup
60 nasal
75 infrior
110 temporal
What does homonomous mean?
Is it on the same side of the vertical meridien?
What are the two lhon genes
11778 worse prog
14484 better prog
Whats behrs syndrome?
Infant hereditary optic neuropathy autosomal recess
Mr
Incontinence
What is tensilon?
Ach-ase inhibitor
Therefore puts ach there
Whats lambert eaton?
Mg-like syndrome
But problem is no release of ach from presynaptic terminal
How does lambert eaton present?
Fatigue in the am that gets better over the day
What malignancy is lambert eaton associated with?
Sc lung ca
Whats kerns sayre?
Cpeo
Pigmentary retinopathy
Heart block
Order of muscles effected by thyroid
Imslo
Whats oculopharyngeal dyatrophy?
Cpeo w dysphagia in french canadians
Whats the #1 modifiable risk factor for thyroid orbitopathy?
Quit smoking
Whats the pathway of a horizontal saccade if you want to look right?
Left frontal eyefields–> parietal eye fields–> superior colliculus of midbr–> pprf that connects cn3 and 6
What part of the brain are you testing w an okn drum?
Parietal lobe bc youre checking the horizontal saccade pathway
Whats the pathway for vertical saccades?
Frontal eye fields–> ipsilateral rostral interstitial nucleus of the mlf
Whats the interstitial nucleua of cajal?
Integrates the saccadic signals for upgaze and downgaze
Name 4 causes of slow saccades
1) pprf lesion
2) ino
3) anticonvulsants
4) paraneoplastic sx
What causes an ino?
Disruption of mlf extending from midbr to pons
What are two causes of ino
Ms
Stroke
How does ino present?
Ipsilateral adduction deficit w contralateral abduction nystagmus
Whats one and a half syndrome? (Right side)
Right mlf = cannot adduct od
Ipsilateral cn6 or pprf= cannot abduct od and yoke cannot adduct os bc pprf controls total gaze to the right
All thats left is contralateral cn6 abduction
What does “supranuclear” mean?
Involuntary control centers in the cortex
What would a stroke of the right frontal eye fields cause?
Eyes deviate toward the lesion (to the right) bc of unopposed signaling from left frontal eye fields
What are the 4 signs of dorsal midbrain syndrome?
1) upgaze palsy
2) colliers sign(bl lid retraction)
3) light near dissociation
4) convergence retraction nystagmus (on attempt to look up eyes nystagmus)
Whats the ddx of light near dissociation?
1) adies pupil (decr parasymp inn to pupil)
2) syphillis
3) dorsal midbr syndrome
What are 4 findings in psp?
1) slow saccades esp DOWNwARD
2) rigidity
3) dysphagia
4) apraxia of lid opening ( cant open eyes)
Fatal in 6 yrs
What are the findings in convergence spasm?
Miosis
Blurry vision
Et
Rx w cyclogyl and weak minus lenses
Whats the 1 finding in convergence insufficiency?
**Exotropia greater at near than distance of at least 10 pd **
Cannot bring eyes in
Rx w pencil pushups
Whats a skew deviation?
A hyper or hypo that doesnt fit into cn4 palsy. Its caused by vestibular issue
Whats miller fisher syndrome?
Variant of guillian barre
Goes from top down
Causes cn6 palsy
Anti Gq1b
Whats pendular nystagmus?
Both phases of the nystagmus are slow
Whats jerk nystagmus?
Type of nystagmus that has a slow and fast phase
Whats infantile nystagmus syndrome?o
Starts in first mnths of life
Can be jerk or pendular
Picks up w monocular occlusion
Can treat w kestenbaum procedure
Whats latent nystagmus?
Occurs w infantile et
Quick phase toward the fixing eye
4 causes of downbeat nystagmus
1) ms
2) lithium
3) arnold chiari (malformation of posterior fossa allows downward herniation thru foramen magnum)
4) mag deficiency
What causes upbeat nystagmus?
Midbr or cerebellar lesion
Ms
Tumor
What type of nystagmus does ms cause?
Any type!!’
Bc there can be demyelinating lasions in any part of brain
What area of brain does torsional nystagmus localize to?
Ponto-medullary junction
Where does see saw nystagmus localize to?
Sella
Whats periodic alternating nystagmus and how to treat?
Nystagmus switches directions q minute.
Seen in ms
Rx w baclofen
Where does ocular bobbing localize to?
Pons
Whats see saw nystagmus?
One eye goes down and the other goes up
What drugs can you use for oscillopsia from nystgmus?
Baclofen
Gabapentin
Memantine
Whats opsoclonus (very testable)
Saccadomania!!
What are causes of opsoclonus?
Infectious
Paraneoplastic (neuroblastoma in kids!!!!)
Drugs
Get mri
Whats superior oblique myokymia?
Spasm of cn4
How do you treat sup oblique myokymia? 3 possibilities
Propranolol
Ganapentin
Superior oblique tenectomy
What should u suspect w pain and cn3 signs?
Pcom aneurysm
Whats webers syndrome
Cn3 w contralat hemiparesis
Whats benedicts syndrome
Cn3 palsy w contalateral tremor
Whats the ddx of multiple cn palsy?
Pituitary apoplexy
Cav sinus
Growing tumor
Tolosa hunt(inflamm of cav sinus)
How does pituitary apoplexy present?
Labile bp
Adrenal insuff
Give hydrocortisone immediatly
Findings in iih?
Opening pressure >250 mm h2o Normal neuroimaging Empty sella Nausea Enlarged bs Papilledema Tinnitus Choroidal folds
How do you work up iih?
Check mri and mrv ( thrombosis of cerebral sinus) and LP
How would a lesion of superior optic disc present of vf?
Inf altitudnal defect
How does a lesion of the papillomacular bundle present on vf?
Cecocentral scotoma or central scotoma
How does infarct of nfl present on vf?
Arcuate scotoma
Whats cecocentral scotoma?
Connecta blond spot to center
Whats the most common cause of an altitudnal defect on vf?
Naaion
Whats the ddx of enlarged bs (4 things)
- Mewds
- Papilledema
- Od drusen
- Tilted nerve
Most common cause of cecocentral or central scotoma?
Compressive lesion
toxic
nutritional
optic neuritis
Most common cause of superior alt defect?
Optic neuritis
Whats the ddx of bl optic neuropathy 4 things
1) nutritional
2) toxic
3) lhon
4) compressive
What types of vf do you think “its an on problem?”
Cecocentral scotoma
Central scotoma
Altitudnal
Arcuate
Most common vf in naaion?
Inferior altitudnal defect
If the defect respects the vertical meridian what does that mean?
Defect is behind chiasm
Vf respects the horizontal meridian what does that mean?
Its an on problem
Whats the ddx of atypical optic neuritis?
Lyme
Sarcoid
What to think of w papilledema?
Tumor
Pseudotumor
What imaging study to get w bitemporal hemianopsia?
Mri w gad
Why get gad on a scan?
Enhances tumors
What kind of vf do you get w willibrands knee lesion?
Unilat complete scotoma and otherside temporal scotoma (bc of crossing nasal fibers)
If you get a unilateral temporal defect respexting vertical midline wheres the defect?
Pituitary tumor until proven otherwise!
Where is meyers loop?
Temporal lobe
Where does inferior quadrantopia localize to?
Parietal lobe
You see left sides bilat homon hemianopsia which tract effected and which eye has apd?
Right optic tract
Left apd
What does incomplete third mean?
Not all muscles involved
How do you charterize cn3 palsy?
- Complete vs incomplete
2. Pupil involved vs not involved
What causes abbarent regeneration of cn3?
Tumor
NOT vascular
How is superior rectus innervated?
Contralat cn3 nuc
How is levator innervated?
Single midline subnucleus innervates both levators
Name 4 causes of pupil sparing 3rd
1) vascular
2) mg
3) gca
4) ms
What innervates so?
Contralateral cn4 nucleus
Whats in the cavernous sinus?
3,4,51,52,6,ica w sympathetics on it
Whats the three step test
1) which is hyper
2) gaze
3) tilt test
Name 3 causes of cn4 palsy?
1) mg
2) trauma
3) ichemia
What can a lesion of the clivus bone cause?
Cn6 palsy
Whats gradinegos syndrome
6th n palsy from mastoiditis
How does cn6 palsy get worked up if pt less than 60 w no ischemia signs?
Mri look for cav sinus tumor, compression, ms
Whats the finding when u put cocaine in horners person?
Normal pupil dilates
Abnormal pupil does not dilate
Whats millard grubler syndrome?
6th nerve nuclear syndrome- lesion in pons
Ipsilat 6th
contralateral hemiplegia
ipsilateral facial palsy
What happens when u put apraclonidine in horners
Normal pupil does not dilate
Abnormal pupil does dilate
Ddx of choroidal folds
Tao
IIH
Posterior scleritis
How is the mr lr io ir innervated?
Ipsilateral cn3 nuc
Triad of spasmus nutans and w/u
1) low amp high freq nystagmus
2) head bobbing
3) torticollis
Get mri
What % of pple will have naion in OThER eye?
15%
What % of pple w optic neuritis have pain?
90%
Whats a defining feature of congenital nystagmus?
Increase slow phase velocity over time
whats the finding in a CN6 NUCLEUS deficit?
1) ipsilateral gaze palsy- eg right 6th nuc out = unable to look right both eyes
2) ipsilateral facial palsy
what type of nystagmus has a VF deficit?
see saw bc localizes to sella
what type of nystagmus with defect of central tegmental tract? (midbr and pons)
oculopalatal myoclonus
a lesion to the MLF can cause INO and what else?
skew deviation
which cn palsy can you get in IIH?
CN6- causes horiz diplopia 2/2 incr intracran pressure. They should not get vertical diplopia bc cn3 should not be involved.
what are 2 types of vf defects you can get in IIH?
1) enlarged BS
2) arcuate glaucoma-like defects
an you get an APD in IIH?
Yes, if papilledema is asymmetric
what type of nystagmus do you get with lesion of the central tegmental tract (runs from pons to medulla)?
oculopalatal myoclonus
early male balding, difficulty releasing grip, cardiac conduction defects- which disease?
myotonic dystrophy
what else can cause optic neuritis besides MS?
sarcoid, lupus, syphillis
this is “atypical” ON- consider it esp when there florid papilledema w heme
who gets ophthalmoplegic migraines and how does it present?
children
migraine w cn3 palsy
why can a right INO cause a right hyper w right incyclotorsion (in addition to adduction deficit on that side?)
it causes a skew deviation b/c the MLF also gets vestibular input from the ear
if a young woman comes in c/o scotoma w/o retinal dz or onh dz, but on hvf has an enlarged BS, how should you work up?
mfERG
could be IBS (idiopathic blind spot syndrome) may show focal retinal problem
what causes oculopalatal myoclonus?
brainstem stroke. The nystagus usually presents years after the stroke
pt presents with normal eye exam and numb chin, what should you ask about?
h/o of cancer-
malignancies associated with mental neuropathy are lymphoma and breast ca
injection of intracameral moxifloxacin at the end of cataract surgery has been asscoaited with what type of inflammation?
TASS
when there is ONH swelling, whats the next question you should ask?
are there disc hemorrhage
hemorrhages- most likely NAION (infarction of the ONH)
No heme- more likely optic neuritis
optic neuritis- how long does it take to recover to baseline vision?
85% return to baseline within 3 months
what would make optic neuritis atypical?
bilateral
age >50
no pain
if you have optic neuritis w no white matter lesion- whats the chance you will dev MS in 15 years?
25%
if you have optic neuritis and 1 white matter lesion whats the chance you will dev MS in 15 years?
75%
what should you never give to a pt w optic neuritis?
oral prednisone
what MUST you have on exam to dx NAAION?
ONH swelling (hyperemic)
Whats the visual prognosis in NAION?
1/3 get better, 1/3 stay the same and 1/3 get worse
whats the typical vision in NAION?
20/40
if they are LP or worse think AION
Why does disk and risk cause NAION?
crowding of structures in ONH, decreased axoplasmic flow
what type of VF defect in NAION?
inferior alt defect or central scotoma
NAION in one eye whats the chance of getting it in the other eye?
20%
how do you treat AION if they have visual loss
1g solumedrol x 3 days
followed by prednisone 1mg/kg/day
how do you treat AION if they don’t have visual loss?
prednisone 1mg/kg/day and order TA biopsy (increased your yield by 5%)
whats the ddx of bilateral ONH edema?
malig HTN- headache, double vision (6th), check BP
ONH drusen->do bscan
papilledema-
papilledema VF
Enlarged BS
pale nerve must rule out infiltrative dz or mass cannot say naion wo seeing onh edema
n/a
if pt c/o worsening vision over months w pale nerve and decr color vision whats next step?
image
how does LHON present? who gets it
mitochondrial
high-school aged male
bilateral hyperemic discs
gradual loss of vision in one eye then the other
may get worse symptoms with hot bath or exercise (uthoff phenomenon)
vision 20/200
bilateral central or cecocentral scotoma
which LHON gene has better/worse prognosis
14484- better
11778- worse
What do you do w pupil involving 3rd?
Image
What do you do in a complete pupil sparing 3rd?
Nothing
What do you do in an incomplete (not all muscle effected) and pupil sparing 3rd?
Image
Where does benedicts localize to?
Redn in midbr
Where does claude sx (3rd w ataxia) localize to?
Area between red n and cerebral peduncle
Where does webers (3rd w hemiparasis) localize to?
Cerebral peduncle (top of micky ear) in midbrain
Blown pupil who walks into office and cn3 otherwise fine likely dx
Adies
after damage to the nnfl how long does it take for ON atrophy to appear?
1 month
what plt count is suspicious for GCA?
> 400,000
where is the pprf located?
pons
wheres the interstitial nuc of cajal?
midbrain
according to the ontt, what % of pts w ON present with PAIN
92%
whats the biggest difference between papilledema from mass and onh swelling from other causes
papilledema tends to have good vision until late in the course.
ONH edema from other causes tends to have shit vision right from the start
whats a good way of distinguishing between foster kennedy and pseudo foster kennedy?
foster kennedy- papilledema due to a mass will have a gvf of EBS 2/2 papilledema
pseudo foster kennedy 2/2 sequential naion should have gvf looks like naion (ie inferior arcuate)