Brainscape's Knowledge GenomeTM

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


See full index

OP2202 > 8. How to: Lens selection > Flashcards

8. How to: Lens selection Flashcards

1
Q

Can you select a lens for a patient?

A

You can never decide, you can offer the options available and allow the Px to make a choice

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

True or false- soft hydrogel lenses moulds to the shape of the cornea?

A

True

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

Which lenses are bigger or smaller compared to the cornea- Soft CL or RGPs?

A

Soft hydrogel lenses: Larger then cornea
RGP: Smaller then cornea

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

How are RGP lenses designed?

A

To match the profile of the cornea

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

2 reasons why RGP lenses not that common?

A
  1. They are not comfortable- takes 2 weeks for the cornea to desensitize and build up on the wearing time.
  2. They are ordered on exchange: patients need to come back to get the perfect fitting.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

FT meaning

A

Full time

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

Is it a concern if Px with orthokeratology lens are wearing them overnight?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

EW meaning

A

Extended wear

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

If wearing lenses more then 3 times a week, what option is cheaper- monthly or daily lenses?

A

Monthly lenses cheaper in this case.

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

Meaning of SV?

A

Single Vision

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

Meaning of MF

A

Multifocal

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

Can you have prism into CL?

A

No

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

What is a soft CL?

A

Plastic which contains varying amount of water.

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

What does it mean when a materials name ends with “filcon”?

A

This is a material used for soft CL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

HT Meaning on lenses?

A

Handling tint- bluish hue on lenses

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

Base curve relates to?

A

Curvature of the back surface

17
Q

TD- Total diameter relates to?

A

This is the overall size of the lens

18
Q

Why do silicone lens have a lower water content?

A

Because they have silicone that transports much more oxygen and hence, a lower content of water is required. This also reduces dehydration of the lens. Hence, better in Px with dry eye.

19
Q

Silicone lenses are sifter then hydrogels, why?

A

Lower water content in comparison.

20
Q

Silicone vs hydrogel lenses, which lens has a lower deposition rate?

A

Standard hydrogels

21
Q

Silicone vs hydrogel lenses, which lens has greater oxygen permeability?

A

Silicone hydrogels

22
Q

Silicone vs hydrogel lenses, which lens is more expensive?

A

Hydrogels

23
Q

Silicone vs hydrogel lenses, which lens is suitable for EW?

A

Silicone hydrogels

24
Q

Silicone vs hydrogel lenses, which lens has a risk of hypoxia?

A

Standard hydrogels

25
Q

What question is asked to guide on the type of lens that will be suitable for Px?

A

How often do you want to wear them?

26
Q

What lens is recommended for Px that want to wear lenses 2-3 times a week?

A

Dailies.
RGP not suitable.

27
Q

What lens is recommended for Px that want to wear lenses 3-7 times a week?

A

Fortnightly or monthly disposable soft CL.
Or RGP

28
Q

How does someone’s work relate to the type of lenses selected for a Px?

A

High computer use throughout the day: silicone lens are picked over standard hydrogels since they prevent dehydration.

29
Q

What does HVID stand for?

A

Horizontal Visible Iris Diameter

30
Q

How is HVID measured?

A

Horizontal measurement from limbus to limbus. It gives the idea of total diameter of a lens.

31
Q

By what diameter should soft lenses and RGP lenses be in relation to HVID?

A

Soft lenses: need to be 2mm bigger then HVID.
RGP lenses need to be small by 2mm then HVID.

32
Q

What is the full form of VPA?

A

Visible Palpebral Aperture

33
Q

How is VPA measured? And why is it important?

A

When head in neutral position- it is the lid to lid vertical measurement. It indicates how much space there is between the top and bottom lid. Gives an idea of the challenges during insertion and removal.

34
Q

VPA is more informative in soft lenses fitting or RGP?

A

RGP

35
Q

Pupil diameter is measured in which 3 conditions?

A
  1. Minimum light conditions
  2. Average (normal) light conditions
  3. Maximum light conditions (UV light source used)
36
Q

Why is pupil size measurement relevant epically for hard CL fitting?

A

Because the optical portion that the patient is looking through needs to be bigger then their maximum pupil size.

37
Q

How are CL recorded in the record card?

A

Manufacturer name and lens name
BC / TD/ Power

OP2202 (16 decks)

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