Pharmacological Dilation Of The Eye

Question 1

What is the purpose of pupillary dilation?

Answer 1

• improve visualization of the fundus

- improve visualization increases detection rate of abnormalities

Question 2

Mydriasis

Answer 2

Dilation

Question 3

Miosis

Answer 3

Small pupil

Question 4

Mydriatics

Answer 4

Agent that induces dilation of the pupil

-they aid in the examination of the vitreous, the retina, and the periphery

Question 5

What can facilitate the mydriatics effect?

Answer 5

The use of local anesthetic before instillation

Question 6

How does the anesthetic help mydriasis?

Answer 6

• decreases blinking and tearing and changes the permeability of the epithelium to the mydriatics agent
• reduces any burning or stinging produced by instillation of the mydriatic

Question 7

What color eyes dilate faster?

Answer 7

Light

Question 8

Patients with this disease have smaller pupils and are slower to dilate than normal individuals

Answer 8

Poorly controlled diabetes

Question 9

The older you are the more ______ your pupils are

Answer 9

The more miotic pupils

Question 10

Increase in age does what to latency time to dilate

Answer 10

Increases

Question 11

Side effects of dilation

Answer 11

• blurred vision (near)
• photophobia
• decreased ability to recognize low-contrast hazards
• increased glare sensitivity
• impaired driving
• angle closure event in pts with narrow anterior chamber depth
• warn patients
• document

Question 12

What muscle does the sympathetic pathways innervate

Answer 12

Dilator

Question 13

Parasympathetic pathway innervates what muscle?

Answer 13

Sphincter

Question 14

Cholinergic drugs

Answer 14

Agonists

Antagonists

Question 15

What is another name for agonists

Answer 15

Parasympathomimetics

Question 16

What do agonists (parasympathomimetics) cause

Answer 16

• iris sphincter contraction-miosis

- ciliary body contraction-accommodation

Question 17

What is an example of an agonist

Answer 17

Pilocarpine

Question 18

What is another name for antagonist

Answer 18

Anticholinergic

Question 19

Antagonists (anticholinergics)

Answer 19

• inhibits cholinergic receptors
• causes pupillary sphincter inhibition-mydriasis
• causes ciliary body inhibition-cycloplegia

Question 20

Examples of antagonists (anticholinergic)

Answer 20

Tropicamine, cyclopentolate, atropine

RED CAP

Question 21

What causes sphincter inhibition (mydriasis)

Answer 21

Antagonists

Question 22

What causes ciliary body inhibition (cycloplegia)

Answer 22

Antagonists

Question 23

What causes sphincter contraction (miosis)

Answer 23

Agonists

Question 24

What causes ciliary body contraction (accommodation)

Answer 24

Agonists

Question 25

Antagonists ST ACH

Answer 25

Scopolamine, tropicamide, atropine, cyclopentolate, homatropine

Question 26

What is the drug of choice for routine mydriasis?

Answer 26

Tropicamide

Question 27

Why is tropicamide the drug of choice for routine mydriasis?

Answer 27

Fastest onset and shortest duration of action of mydriatic effects

Question 28

What does tropicamide equivalent in mydriatic effect to?

Answer 28

0.5% and 1%, greater cycloplegia with 1%

Question 29

Side effects of tropicamide

Answer 29

- stinging upon instillation | - transient increase IOP in POAG patients

Question 30

Contraindications and precautions of tropicamide

Answer 30

No reported adverse systemic effects

Question 31

What is the most potent mydriatic/cycloplegic currently available?

Answer 31

Atropine

Question 32

What do you use when you want completel cycloplegia

Answer 32

Atropine

Question 33

What is the drug of choice for routine cycloplegic refraction?

Answer 33

Cyclopentolate

Question 34

Weak but prolonged cycloplegic effect and strong mydriatic effect make it suitable for uveitis therapy

Answer 34

Homatropine

Question 35

What drug do you typically use if patient is allergic to the others?

Answer 35

Scopolamine

Question 36

Which one crosses blood brain barrier easier?

Answer 36

Scopolamine

Question 37

What causes stimulation of iris dilator muscle? (Mydriasis)

Answer 37

Direct alpha-adregnergic agonist like phenylephrine

Question 38

MOA for indirect alpha-adrenergic agonist

Answer 38

- release of stored norepinephrine | - inhibits reuptake of norepinephrine

Question 39

When is phenylephrine commonly used?

Answer 39

In combination with anticholinergic to produce maximal dilation of the pupil -2.5% commonly used in combination with tropicamide for routine dilation

Question 40

Contraindications and precautions of phenylephrine

Answer 40

-adverse cardio events with 10% that's why you use 2.5%!

Question 41

Side effects of phenylephrine

Answer 41

- ocular: mild stinging, pigmented aqueous floaters | - systemic: acute systemic hypertension, ventricular arrhythmia, tachycardia, subarachnoid hemorrhage

Question 42

What is used when someone has hornrs syndrome?

Answer 42

Hydroxyamphetamine

Question 43

What is the preferred method of delivery for eye drop instillation

Answer 43

Inferior fornix delivery

Question 44

Why is inferior fornix delivery preferred?

Answer 44

- maximizes ocular contact time of drug - minimizes drug lose - increases ocular absorption - decreases systemic absoprtion

Question 45

Alternatives to instilling eye drops

Answer 45

- medial canthus delivery - spray bottle - pledgets