Dilation Flashcards
(86 cards)
1
Q
purpose of dilation
A
- improve visualization of the fundus
- improve visualization increases detection rate of abnormalities
2
Q
Is dilation required for a thorough evaluation of ocular structures?
A
-according to the AOA it is
3
Q
who should be dilated?
A
ALL patients
4
Q
How often should you get a comprehensive eye exam?
A
18-39 should be at least every 2 years
65 and older, every year IN THE ABSENCE OF OCULAR CONDITION
5
Q
when else should you dilate?
A
- patients with previous ocular pathology
- patients with high risk of intraocular disease
- patients that come in with certain chief complaints
6
Q
if people are sensitive to dilation drops, what are they sensitive to?
A
-the preservative
7
Q
when you see someone with_______, you should not dilate
A
- narrow anterior chamber angle
- iris-fixed intraocular lens
8
Q
why is history important before dilation?
A
- guides the DFE
- aids in what you are looking for during ophthalmoscopy
9
Q
Why should you do VA?
A
- before any procedure for legal reasons
- detect refractive error, problems with retina, optic nerve, etc
10
Q
Do all disorders affect VA?
A
-nope
11
Q
pupil reflexes
A
- screen for abnormalities prior to dilation
- determine if vision loss is macular or optic nerve related
- VERY important when people have APD and decreased acuity in one eye
12
Q
normal range of IOP
A
8-23 mmHg
average: 15.5
13
Q
when is a difference in pressure between two eyes considered significant?
A
-difference more than 2 mm Hg
14
Q
what time of day are pressures higher?
A
-morning
15
Q
Diurnal variations of what are considered normal?
A
3-4 mm Hg
16
Q
What patients will see a elevation of IOP after dilation?
A
-open angle glaucoma
17
Q
how do pressures change in age?
A
-increase
18
Q
What are the three ways you check IOP?
A
- digital palpation
- non contact tonometry
- goldman
19
Q
advantages of digital palpation
A
- simple
- inexpensive
- no instrument
- good when external tonometrty is not possible
- when patients are unable to do other methods
20
Q
Disadvantages of digital palpation
A
- least accurate
- you should avoid in eyes with trauma or in post op conditions
21
Q
what fingers do you use for digital palpation?
A
-two pointer finers
22
Q
soft IOP
A
less than 6-8
23
Q
Hard IOP
A
greater than 30
24
Q
using other body parts, what does the eye feel like?
A
- nose is normal
- chin is hard
- cheek is soft
25
should you record time for digital palpation?
-hell yea
26
NCT
- cornea is applanated by air pulse
- IOP mesured without direct contact between eye and instrument
- useful when there are infections
27
advantages of NCT
- quick
- no anesthetic
- can be delegated to tech
- no epithelial damage
- measure through contact lenses
28
disadvantagegs of NCT
- cost
- large instrument
- less portable
- must be factory callibrated
- multiple readings necessary
- most patients hate it
29
applanated
-force it takes to flatten the cornea
30
a narrow anterior chamber angle increases risk of?
angle closure glaucoma
31
shadow test book definition
-anterior chamber depth estimated with oblique penlight illumination across the surface of the iris
32
three ways to evaluate anterior cahmber depth
- shadow test
- slit lamp
- gonioscopy
33
shadow testttttt
- GROSS ESTIMATION
- used only when slit lamp is not available
- light is presented from temporal side
34
what level of brightness should you do shadow test?
FULL ILLUMINATION
35
grade 1
-less than 1/3 iris is illuminated
36
grade 2
-1/3-2/3 illuminated
37
grade 3
2/3 illuminated
38
grade 4
fully illuminated
39
what should you warn patients with narrow anterior chamber angles about?
- signs and symptoms of angle-closure glaucoma
| - could have increases of IOP after dilation
40
who is more at risk of narrow angle glaucoma?
- older patients
- asians
- women
41
hyperopia
-more likely to have shallow anterior chambers and narrow angles
42
signs of angle closure glaucoma
- severe pain
- blurred vision/halos
- headache
- nausea
- red eye
- dilated pupils
43
is angle closure glaucoma an ocular emergency?
YES
44
go look at summary
do it
45
what is the purpose for dilation?
- improve visualization of the fundus
| - improved visualization means more detection of disease!
46
mydriasis
dilation
47
mydriatics
agent that induces dilation of the pupil
48
why use an anesthetic before instillation of mydriatic?
- decreases blinking and tearing
| - reduces burning or stinging
49
why do light eyes dilate faster?
-less pigment in the iris to sequester the drug
50
what does uncontrolled diabetes have to do with dilation?
-uncontrolled diabetics will have smaller pupils and are slower to dilate
51
increase in age does what?
smaller pupils
| -increase in latency time to dilate
52
miotic
-small pupil
53
side effects of dilation
- blurred vision for near tasks
- photophobia
- decreased ability to recognize low-contrast
- glare sensitivity
- can contribute to angle-closure
54
can you drive with dilation?
yea
55
what is under the sympathetic pathway?
dilator
56
what is under the parasympathetic pathway?
sphincter
57
in general, dilation has what kind of innvervation?
autonomic
58
cholinergic drugs-agonist
- parasympathomimetics
- cause iris sphincter contraction (miosis)
- causes ciliary body contraction(accommodation)
59
what color cap do agonists have
green
60
example of agonist cholinergic drug
pilocarpine
61
cholinergic drugs-antagonist
- anticholinergics
- bind to and inhibit cholinergic receptors
- pupil sphincter inhibition-mydriasis
- ciliary body inhibition- cycloplegia
62
cycloplegia
-inability to accommodate
63
what color cap do antagonists have?
red
64
examples of antagonists
-tropicamide, cyclo, atropine
65
tropicamide
-fastest onset and shortest duration of mydriatic effects
66
what is the drug of choice for routine mydriasis?
tropicamide
67
does the concentration of tropicamide change the effects?
-mydriasis is the same, but cycloplegia is worse in 1%
68
what is the most potent mydiatic/cyclo drug?
-atropine
69
when do you use atropine?
- when you need complete cyclo
| - can last up to 7 days
70
what is the drug of choice for routine cycloplegic refraction?
cyclopentolate
71
cyclopentolate
-faster cycloplegia with less residual accommodation
72
adrenergic drugs-direct
- stimulation of dilator to cause mydriasis
| - no cycloplegia effect!
73
what is an example of adrenergic-direct drugs?
phenylephrine
74
what color cap do adrenergic drugs have?
red
75
indirect alpha adrenergic drugs
-release stored norepi of inhibit reuptake of norepi
76
example of adrenergic-indirect drug
hydroxyamphetamie
77
phenylephrine
- dilation without cycloplegia
| - combined with anticholinergics
78
what is routinely used for maximum dilation?
2.5% phenylehrine with tropicamide
79
side effects of phenylephrine
STINGING
80
what is the preferred method for drop instillation?
inferior fornix delivery
81
why use inferior fornix delivery?
- max ocular contact time of drug
- minimize drug loss
- increase ocular absorption
- decrease systemic absorption
82
what should you do after you have properly instilled the drop?
-punctal occlusion
83
what should you include in the recording of drops?
- name of the drug
- its concentration
- how many drops for each eye
- time
84
what are alternate methods of drop instillation?
- medial canthus delivery
- spray bottle
- pledgets
85
what does pregnancy group C mean?
-tests have been done on animals and have seen bad results, but not done on prego humans
86
should you just out like a million drops in all at once?
- nah
- no anesthetic first, wait 2-5 min, then do dilation
- sit in dark room
