5-autonomic-eyeball!

Question 1

what is accomodation

Answer 1

focusing of the eye

Question 2

what does morphine do to pupil

Answer 2

miosis

Question 3

what does organophostate poisoning do to pupil

Answer 3

miosis

Question 4

what does cocaine do to pupil

Answer 4

mydriasis

Question 5

what does amphetamine do to pupil

Answer 5

mydriases

Question 6

what is mydriasis

Answer 6

dilation of pupil

Question 7

what is miosis

Answer 7

constriction of pupil

Question 8

what causes mydriases

Answer 8

increase in sympathetic outflow

Question 9

what is the role of the pupillary dilator muscle

Answer 9

cause mydriasis with alpha adrenoceptor stimulation

Question 10

what is another name for the pupillary dilator muscle

Answer 10

iris radial muscle

Question 11

what is another name for the iris radial muscle

Answer 11

pupillary dilator muscle

Question 12

what does alpha stimulation do to the pupillary dilator muscle

Answer 12

mydriases

Question 13

what does alpha stimulation do to the iris radial muscle

Answer 13

mydriases

Question 14

what is another name for the circular pupillary constrictor muscle

Answer 14

iris sphincter

Question 15

what is another name for the iris sphincter

Answer 15

circular pupillary constrictor muscle

Question 16

what kind of receptor stimulation happens with the iris sphincter

Answer 16

muscarinic

Question 17

what kind of receptor stimulation happens with the circular pupillary constrictor muscle

Answer 17

muscarinic

Question 18

what kind of receptor stimulation happens with the circular pupillary dilator muscle

Answer 18

alpha

Question 19

what kind of receptor stimulation happens with the iris radial muscle

Answer 19

alpha

Question 20

what kind of activation do ciliary muscles require

Answer 20

muscarinic

Question 21

what does muscarinic activation do to ciliary muscles

Answer 21

contraction

Question 22

what kind of vision does ciliary muscles help with

Answer 22

myopia (near vision)

Question 23

what does the trabecular meshwork do

Answer 23

moves do that fluid can leave through the canal of schlemm

Question 24

what does the canal of schlemm do

Answer 24

let fluid leave the eye

Question 25

what causes the trabecular meshwork to move

Answer 25

ciliary muscle activation

Question 26

how do ciliary muscles help with removing aqueous humor

Answer 26

puts tension on trabecular meshwork which opens pores to let outflow of aqueous humor in canal of schlemm

Question 27

what does the ciliary epithelium do

Answer 27

produces the aqueous humor

Question 28

what kind of receptors stimulate the ciliary epithelium

Answer 28

beta

Question 29

how do beta blockers reduce IOP

Answer 29

reduces aqueous humor release from the ciliary epithelium (ciliary epithelium has beta adrenergic receptors)

Question 30

how do muscarinic agonists reduce IOP

Answer 30

because it activates ciliary muscles which activates trabecular meshwork to open pores and let aqueous humor out into the canal of schlemm

Question 31

what is galucoma and what can it cause

Answer 31

elevated IOP and it can cause optic nerve damage and blindness

Question 32

what are the two types of glaucoma

Answer 32

open angle and angle closure glaucoma

Question 33

what is open angle glaucoma

Answer 33

high pressure between cornea and iris

Question 34

how common is open angle glaucoma and how easily is it treated

Answer 34

common and easily treated

Question 35

what is angle closure glaucoma

Answer 35

high pressure between ciliary body and iris

Question 36

how common is angle closure glaucoma and how easily is it treated

Answer 36

not as common and doesnt respond as well to drugs :(

Question 37

what is the course of treatment for open angle glaucoma (4)

Answer 37

- beta blocker (stop ciliary body secretion) - cholinergic agonist/cholinesterase inhibitor (preserve sympathetic tone) - add adrenaline or apraclonidine (with b blocker still)(reduces blood flow to ciliary body) - carbonic anhydrase inhibitor (affects ciliary body secretion)

Question 38

why is it safe to take glaucoma meds if you have systemic circulation issues

Answer 38

the eye drops have very poor access to systemic circulation

Question 39

what is Timolol (drug class)

Answer 39

betablocker

Question 40

what is the difference with timolol and propranolol

Answer 40

timolol has no anesthetic effects (dont want that in the eye)

Question 41

what does Timolol do

Answer 41

reduces secretion of aqueous humor from ciliary body and lower IOP

Question 42

what is pilocarpine (drug class)

Answer 42

muscarinic agonist

Question 43

what does pilocarpine do

Answer 43

cause ciliary muscle contraction | increase outflow of aqueous humor into circulation, reduce IOP

Question 44

what are the untoward effects of pilocarpine

Answer 44

miosis (by iris sphincter) | myopia (by ciliary muscle)

Question 45

what is physostigmine

Answer 45

anticholinesterase

Question 46

what does physostigmine do to eye

Answer 46

ciliary muscle contraction, increase outflow of aqueous humor, reduce IOP

Question 47

what does apraclonidine do

Answer 47

vasoconstrict, reduce blood flow to ciliary body, less aqueous humor secreted, IOP decreased

Question 48

what do cannabinoids do to eye

Answer 48

lower IOP likely by relaxing the trabecular network

Question 49

what is anandamide

Answer 49

endogenous ligand of the CB1 and CB2 receptors

Question 50

what do CB1 receptors do (g protein)

Answer 50

Gi which reduces NT release by activating Ca2+ and GIRK channels

Question 51

what direction does GIRK channels go

Answer 51

releases K+ from nerve terminal!

Question 52

what does atropine do to the eye

Answer 52

dilate pupil for ocular examination

Question 53

what kind of drug is atropine

Answer 53

muscarinic antagonist

Question 54

why does atropine cause mydriasis

Answer 54

muscarinic antagonist, meaning it removes the parasympathetic tone to cause dilation (mydriasis)

Question 55

what causes Horner's syndrome

Answer 55

head trauma or stroke in brainstem | even if the damage is unilateral

Question 56

can damage to sympathetic nerves cause horners syndrome

Answer 56

yes thats what it is about

Question 57

can damage to parasympathetic nerves cause horners syndrome

Answer 57

no

Question 58

what characterizes horners syndrome

Answer 58

interruption of oculosympathetic pathway somewhere between hypothalamus and eye

Question 59

what are the 3 neurons that could be damaged to cause horners syndrome

Answer 59

1-hypothalamus to spinal cord 2-sympathetic preganglionic neuron 3-sympathetic ganglion neuron

Question 60

what would you expect cocaine to do to the pupil

Answer 60

cause dilation

Question 61

if cocaine doesn't cause pupil dilation, where would the lesion be

Answer 61

neurons 1 2 or 3

Question 62

how can you use amphetamines to test for horners syndrome

Answer 62

test neuron 3 -if it is intact, the pupil will dilate (it releases NA REGARDLESS of the condition of neuron 1 and 2 or sympathetic outflow to neuron 3)

Question 63

in summary, what do alpha adreoceptor agonists do to eye

Answer 63

``` lowers IOP (decrease flow to ciliary body) mydriases (increase pupil size from pupillary dilator/iris radial muscle) ```

Question 64

in summary, what do muscarinic agonists do to eye

Answer 64

``` miosis (pupillary constrictor/iris sphincter) myopia (ciliary muscle contraction, accomodation for near vision) lower IOP (contract ciliary muscle - tension on trabecular meshwork - aqueous humor squeezed out into circulation) ```

Question 65

in summary, what do beta adreoceptor antagonists do to eye

Answer 65

lower IOP (blocks humor production by ciliary body)

Question 66

why can atropine be bad for glaucoma

Answer 66

antimuscarinic (stops parasympathetic tone) | it can relax the ciliary muscle