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Flashcards in Pupillary Pathway Deck (48)
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1

near pupil response pathway efferent

cn3 sphincter (miosis) + cb (acc)
-Mr convergence

2

consensual pupillary light response

constriction of contralateral eye

3

dorsal midbrain- pineal gland

-paralysis of upgaze bilateral
-convergent refraction syndrome- eyes converge with trying to look up
-eyelid retraction

4

Disruption of the efferent sympathetic pathway: Horner syndrome
pathway - preganglionic

spinal cord --> apex of lungs --> superior cervical ganglion

5

disruption in the central nervous system pathway causes

lesion of the midbrain can affect the tract between the pretectal and EW nucleus

6

dorsal midbrain syndrome

-bilateral light - near dissociation
-pupils are normal to mid-dilated
-most commonly due to pineal gland abnormality

7

in efferent sympathetic pathway is anisocoria better or worse in dim illumination

worse

8

efferent parasympathetic pathway causes- cn3 palsy

-also innervates sr, mr, io, ir, levator sphincter, cb
- ischemic lesion --> pupils spared
-aneurysm --> pupils involved

9

causes of RAPD retina

large lesion needed bc fibers are spread out

10

physiological anisocoria

-20% of pop, can switch eyes
- more apparent in dim illumination - sympathetic, but no other problem
- <1 mm difference
-reactive to light + acc
- no dilation lag (usually seen w/ horner's)

11

RAPD brachium

RAPD with normal vision (only place this happens)

12

efferent parasympathetic pathway cause- pharmacologically dilated pupil

-fixed dilation, worse in bright
-pharm testing 1% pilocarpine
-0.13% pilo --> constriction = tonic
-1% pilo --> remains dilated --> pharm dilated pupil

13

what is light-near dissociation

near pupil response bypasses the central portion of the pupillary light response
-acc, convergence, miosis

14

argyll roberston pupil

-bilateral light near dissociation
(-) light (+) acc
-without light stimulus the pupils will be very small <1mm
-most commonly due to neurosyphilis
also due to Dm, chronic alcoholism , ms
-lesion likely in central light pathway

15

Pharmacologic testing
1. Diagnostic: 5-10% ophthalmic cocaine
a. Indirect acting adrenergic agonist

normal = dilation
horner's= no dilation

16

efferent lesion light near

affects near + light response due to overlap of pathway

17

cataracts and RAPD

cataracts do not cause an ipsilateral RAPD
-cataract --> spreading light --> more fibers simulated --> other eye may look like it has APD
-if cataract and APD then its not cause- look for something else

18

efferent parasympathetic pathway cause- tonic pupil

-caused by damage to the ciliary ganglion or short ciliary nerves
-segmental constriction- only segment of iris constriction (purse-string effect- not uniform constrction -slow)
-decreased corneal sensitivity
-slow and prolonged near pupillary response (light near dissociation)
-cholinergic denervation supersensitivity
(when some nerves are damaged the remaining nerves are supersensitive; dilted 0.13% pilocarpine will constrict these nerves)

19

pancoast tumor

tumor at apex of lungs
- injury to thoracic area (heart surgery)

20

efferent parasympathetic pathway cause- damage to iris

trauma- post surgery
inflammation- syneichiae
ischemia- due to angle closure, will have high pressure

21

RAPD grading
grade 3

immediate dilation

22

horner's + cn6 palsy

look @ cav sin likely aneurysm of ICA within sinus, cannot abduct, ptosis, miosis

23

causes of RAPD optic nerve

very small lesion --> very large APD b/c fibers are compressed

24

3. Alternative diagnostic agents
b. 1% phenylephrine

normal= minimal dilation
horner's= a lot of dilation due to super sensitive post ganglion

25

efferent

leaving CNS (motor) going to eyeball

26

efferent parasympathetic pathway cause- tonic pupil causes

1.autonomic- bilateral, diabetes
2. orbital mass- unilateral
3. orbital trauma/surgery - unilateral
4. idiopathic (adie tonic pupil)

27

direct pupillary light response

constriction of ipsilateral eye

28

RAPD optic tract

get APD contralateral to the lesion with complete homonymous hemianopia more nasal
-more nasal fibers cross at chiasm --> see on opposite side

29

RAPD grading
grade 1

grade 1- weak constriction followed by greater redilation

30

afferent

brings info to CNS, ON, retin