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Flashcards in The pupil Deck (17):
1

What influences the resting position of the pupil?

Sympathetic and parasympathetic innervation

2

What is miosis?

Constriction of the sphincter muscle in the iris by CNIII

3

What is mydriasis?

The iris dilator muscle dilates the pupil via sympathetic chain

4

What is anisocoria?

Unequal pupil size (physiologic and pathologic)

5

What is physiologic anisocoria? How frequent is it?

< 1mm asymmetry, both pupils equally reactive
25% of population

6

What is pathologic anisocoria?

>1mm difference in asymmetry
pupils react different
pupil size difference in light vs. dark conditions

7

What causes mydriatic disorders? List a few

Abnormal pupil is unable to constrict causing greater asymmetry in light
CNIII palsy, acute angle closure glaucoma, Adie's pupil , traumatic mydriasis (iris trauma or surgery), dilating/Cycloplegic drops

8

What causes miotic disorders? List a few

Abnormal pupil is unable to dilate, causing greater asymmetry in the dark
Horner's, iritis, cholinergic, anticholinesterase inhibitor drugs (pilocarpine, carbachol)

9

What is the pathway of pupillary light reflex?

Light stimulates retina--> pretectal nucleus in the mid brain
Pretectal nucleus--> both edinger Westphal nuclei
Edinger Westphal --> ciliary Ganglion
Ciliar ganglion--> sphincter muscle in both pupils

10

What does RAPD indicate? ( relative afferent pupillary defect)

Damage to the afferent visual system (retina or optic nerve)

11

What causes RAPD? (examples)

Optic nerve disease: trauma, optic nerve glioma, glaucoma, optic neuritis

Retinal disease: retinal detachment, central retinal artery or vein occlusion

12

Would cataracts cause RAPD?

No

13

Would corneal scar cause RAPD?

No

14

Would refractive error cause RAPD?

No

15

Would vitreous hemorrhage cause RAPD?

No

16

Would cortical blindness cause RAPD?

No

17

Would functional visual loss cause RAPD?

NO