Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OD1 Semester 2 - Integrated Ophthalmic Sciences and Preclinical Optometry > Posterior Segment Examination - Week 1 > Flashcards

Posterior Segment Examination - Week 1 Flashcards

1
Q

Why dilate?

A
  • improved view of retina
  • for binocular viewing: enhanced image quality
  • for better detection of diseases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Indications for dilating:

A
  • new patient
  • routine every 2 years
  • flashes and/or floaters
  • unexplained vision loss/reduction
  • progressive retinal diseases
  • systemic conditions
  • hx of: head injuries, ocular trauma, chronic uveitis, peripheral retinal degen., ocular surgery
  • refractive error: myopia to high myopia, and hyperopia (and anisometropia)
  • limited view of posterior pole

Way to remember:
“New systemic routine flashes are progressive and unexplained. Check patient’s refractive error and history for disease and injury”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How often should you routinely dilate a patient? (Given no other problems)

A

Every 2 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why should you dilate if the patient has flashes and/or floaters

A

Flashes/floaters are caused by anything that can pull on the retina or vitreous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Are flashes/floaters an urgent issue?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name an example of a progressive retinal disease:

A

Diabetic retinopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List some examples of systemic conditions:

A
  • hypertension
  • high cholesterol
  • any autoimmune disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What could sudden vision loss be a sign of?

A

Stroke

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How often should you dilate/post eye exam for patient’s who had ocular surgery?

A

Yearly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How often should you dilate a moderate to high myopia patient?

A

3-7D: every 2 years

8D +: yearly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is one reason for limited view of posterior pole of the eye?

A

Cataract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define cycloplegia

A

Is paralysis of the ciliary muscle of the eye, resulting in a loss of accommodation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Considerations for dilation/posterior segment examination

A
  • Hx
  • V.A (vis. Acuity) (subj. refraction needed or just pinhole)
  • pupils testing
  • Accommodation tests
  • Assess potential for angle closure
  • After DFE, warn patient about angle closure symptoms

**
Accommodate your pupils to assess angle of history and V.A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How can you assess potential for angle closure?

A
  • angle: VH (Van Herick) technique
  • iris bowing: iris shadow test
  • depth: smith’s method
  • structures: gonioscopy
  • Anterior OCT (optical coherence tomography)
  • IOP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Contraindications for dilating:

A
  • Angle Closure Glaucoma
  • Px using pilocarpine for Tx of glaucoma
  • dislocation of crystalline, or IOL lens
  • iris fixed or anterior chamber IOL
  • Hyphema (blood in AC)
  • Acute corneal diseases
  • hypersensitivity to mydriatic eye drops

Way to remember:
*dislocate the px’s iris at a fixed angle to treat acute hypersensitivity and Hyphema

Or DIPHAHA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the question mark contraindications for dilation:

I.e there is some digression on whether you don’t dilate

A
  • pregnancy/lactation
  • narrow AC angle
  • recent ocular injury
  • petite/anorexic individuals
  • kids/children –> liver enzyme activity
  • sick/febrile
  • way to remember

Sick pregnant petite kids are sick and narrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Via what 2 main methods can you dilate? Which is more powerful/effective?

A
  • dilator muscle agonist
  • sphincter muscle antagonist

Sphincter muscle antagonist is more effective (because sphincter is the stronger muscle)

18
Q

True or false: sympathomimetics (dilator agonists) cause cycloplegia

A

False

19
Q

True or False: Sphinctor antagonists/anti-muscarinic drugs can cause cycloplegia

A

True

20
Q

Which muscle, when innervated, results in sectoral dilation of the pupil? (Pear-shaped pupil)

A

Dilator muscle

Sphincter does not, instead, sphincter muscle innervation gives max dilation

21
Q

Effects of dilator muscle innervation:

What is unaffected?

A
  • sectoral dilation of the pupil (sectoral mydriasis)
  • widening of palpebral fissure

Pupillary light reflex = unaffected

22
Q

How long does mydriasis take to start and duration after dilator muscle innervation? When is it maximal?

A

Starts in 10 minutes
Is maximal after 60-90min
Can last for 5-7 hours
(Or even 12-24 hours)

23
Q

What drug do we use to innervate the dilator muscle to cause mydriasis?

A

Phenylephrine 2.5% and 10%

24
Q

What happens to the pupillary light reflex when you innervate the dilator muscle? What about the sphincter muscle?

A

Dilator: nothing happens
Sphincter: pupillary light reflex is reduced or abolished

25
Q

Does dilator muscle innervation affect accommodation? What about sphincter?

A

Dilator: no
Sphincter: yes. It does affect accommodation. Causes cycloplegia, resulting in a loss of accommodation

26
Q

Which drugs are used as sphincter antagonists to dilate the pupil?

A

Tropicamide 0.5%, 1%
Cyclopentolate 0.5%, 1%
Atropine 1%
Homatropine 2%

Remember by saying HCAT

27
Q

Which drug is the drug of choice for optometrists for dilating pupils? Why? Is it a dilator agonist or sphincter antagonist?

A

Tropicamide 0.5%, 1%

  • due to its safety profile
  • it’s a sphincter antagonist
28
Q

Is dilator symp or para? What about sphincter?

A

Dilator: innervate by Sympathetic
Sphincter: Parasympathetic

29
Q

How long is the onset and duration for tropicamide?

A

Quick onset and short duration

30
Q

How much tropicamide do you apply for DFE (dilation)? How much do you apply for inducing cycloplegia?

A

DFE: 0.5%
Cycloplegia: 1%

31
Q

Can you apply a 2nd drop of tropicamide? If so, when?

A

If needed, apply 5 minutes after 1st

32
Q

What drug is often used for cycloplegia?

A

Cyclopentolate

  • note: patient asked to attend 1 hour before appointment
33
Q

Rank the systemic adverse affects from worst to least for the following:

  • tropicamide
  • cyclopentolate
  • Atropine
A

1/ Atropine
2/ Cyclopentolate
3/ Homatropine

34
Q

How long do the effects of Atropine last?

A

For days to weeks

35
Q

Which drug is used in amblyopia treatment?

A

Atropine

  • put atropine in good eye to make it blurry. This forces the lazy eye to work
36
Q

What can Homatropine be used for? (Other than dilation)

A
  • used to prevent or breakdown posterior synechiae

Posterior synechiae = when the iris attaches to the lens or cornea
- this causes it to be sticky and closes the anterior chamber

37
Q

What is the use of Alcaine?

A

Local anaesthetic

38
Q

True or false: Alcaine does not sting on installation

A

False. Alcaine stings VERY BADLY

39
Q

Why isn’t Alcaine used on a long term basis?

A

Due to epithelial toxicity; can impair epithelial healing

40
Q

What is an effect of Alcaine on the cornea?

A

Increases corneal permeability

41
Q

For all drugs used, what should you check for and record:

A
  • Px allergy
  • Any known side effects
  • Label, concentration, expiry date

OD1 Semester 2 - Integrated Ophthalmic Sciences and Preclinical Optometry (49 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions