Contacts Soft And Hard

Front 1

Contact rests on the

Back 1

Tearfilm layer of the cornea

Front 2

What produces the power of a contact len?

Back 2

The difference between the front surface curvature and the back surface curvature.

Front 3

Two ways to list k readings?

Back 3

1.list the flat k first followed by the steep k and its axis

2. List horizontal meridians first regardless if its the steep k or not.

Front 4

If the back surface of a lens is to be the same radius as the k's then that is called?

Back 4

Fitting on the k

Front 5

Rgp lens can be fitted?

Back 5

Flatter, steeper , or on the k

Front 6

Soft contacts are fitted how?

Back 6

3-5 diopters flatter than k

Front 7

How is the total lens diameter measured?

Back 7

One edge of the lens to the opposite side.

Front 8

The higher the the minus the ___ the center of the lens. The higher the plus the _____the center of the lens.

Back 8

Thin, thick

Front 9

Why are lenses truncated?

Back 9

It adds stabilty, and prevents rotation.

Front 10

When a base curve lens says it needs to be steeper what happens to posterior radius of the curvature?

Back 10

Its decreased it is opposite if the curvature lens needs to be flatter.

Front 11

How is the wetabililty of a surface measured?

Back 11

Its measured in terms of contact or wetting angle.

Front 12

The lower the wetting angle the greater the?

Back 12

Spreading of tears

Front 13

The oxygen abbreviation in contacts is?

Back 13

Dk

Front 14

What is the minimal safe level of equivalent oxygen percentage (EOP) in dailies, extended wear? Whats ideal for extended wear?

Back 14

9%

12%

18%

Front 15

When the corneas astigmatism is different than the cylinder in the prescription this is known as?

Back 15

Residual astigmatism

Front 16

How is the optic zone determined?

Back 16

The difference bt the diameter and width of the peripheral curves.

Front 17

What are the causes of a 3:00-9:00 staining from contacts?

Back 17

Lid gap, poor blinking , poor tear film.

Front 18

What instrument measures the base curve of a lens?

Back 18

Contacto gauge (radiusscope)

Front 19

How can the power of a lens me measured?

Back 19

Lensometer

Front 20

Describe giant papillary conjunctivitis.

Back 20

Its more common with gas perm, has a cobblestone appearance under the lid.

Front 21

What is a 'tight ' lens

Back 21

A lens that causes hypoxia aka low oxygen causing corneal edema.

Front 22

What causes one to change their blink rate?

Back 22

Awareness of the lens.

Front 23

What are multiple causes of a contact lens causing corneal edema?

Back 23

Flat lens compressing cornea

Steep lens lacking tear flow

Poorly centered lens

Incorrect blinking

Incorrect cleaning of lens

Front 24

Edema can do what to previous k readings

Back 24

Increase

Front 25

How are soft lenses classified ?

Back 25

How their made, water content. Dk permeability, and by their function

Front 26

Advantage a of hydrophilic soft contacts?

Back 26

Comfort, rapid adaptation, lack of spectacle blur, dispisability, minimal lens loss, minimal overwear reaction, protects entire cornea, no corneal abraisions on insert, lack of glare.

Front 27

Advantages of silicone hydrogel?

Back 27

Rapid adaptation, low rate of deposits, easy to handle, high DK value, suitable for extended wear.

Front 28

What are disadvantages of a soft contact?

Back 28

Doesn't corrext high astigmatism, variable vision, lack of durability, faulty duplication, deposit forms, modifications are impossible, disinfect problems

Front 29

How can one disinfect soft lenses?

Back 29

Boiling , chemical, and uv methods.

Front 30

Thing to consider in a patient interested in contacts?

Back 30

Age

Hygiene

Reoccurent infections, susyemic disease, dryness of eyes

Patients motivation

Corneal sensitivity test

Occupation

Lid tension

Front 31

How are soft lenses manufactured and which is the most common?

Back 31

Spin casting, lathecut, and molding methods. Lathe cut and molded are most common.

Front 32

A soft lens should rest on how many points?

Back 32

Three, apex and at the periphery of the cornea

Front 33

When fitting a soft contact lens the goal is to have

Back 33

The flattest lens possible with clear vision and comfort.

Front 34

Symptoms of a tight lens

Back 34

Fluctuating vision

Comfort at first that gets worse throughout the day

Coneal injection around the cornea

Corneal indentation

No movement after blinking

K's that are clear than are distorted after a blink

Retinoscopic reflex is fuzzy than clear .

Front 35

Signs of a loose lens

Back 35

Fluctuating vision

Awareness of lens

Poor centering

Lens falls out

Bubble under lens

Ks that blur after blinking

Retinoscopic reflex that is clear than is fuzzy.

Front 36

The lens is cleaned by rubbing both sides of a lens with a finger for 20 seconds, this is known as?

Back 36

Digital cleaning.

Front 37

What is the minimal time needed to disinfect lenses with peroxide?

Back 37

20 minutes

Front 38

What is bullous keratopathy

Back 38

Described as a corneal blister.

Front 39

Symptoms like flare or streaming lights with contacts could mean?

Back 39

Optic zone is too small

Front 40

Blurring vision in daytime could be a result of

Back 40

The contact lens riding too high or too low

Front 41

Signs that indicate a contact lens needs to be changed or wear time needs to be reduced?

Back 41

Change in k's over 1 diopter and distortion in the mires.

Front 42

What does a contact wetting solution do?

Back 42

Turns surface into a water loving surface making the tear film spread easier.

Front 43

What do soaking solutions do?

Back 43

Cleans lens of oil and sebaceous secretions.

Front 44

What does a cleaning solution do?

Back 44

Cleans lens of oil, mucus, crystalline deposits.

Front 45

What kind of diameter does a tricurve lens have?

Back 45

Large diameter

Front 46

Tinted lenses use what type of scale to note tint intensity?

Back 46

1-3 1 being the lightest.

Front 47

What does it mean when the base curve of the lens is made steeper?

Back 47

Posterior radius curvature is decreased

Front 48

What is a frequent cause of patients rejection of contacts?

Back 48

Edge design

Front 49

What are the peripheral curves designed for?

Back 49

Allows tear flow under the lens

Front 50

Lid gap is more prone in what script and why?

Back 50

High myopes from thickness of periphery of lens

Front 51

Is it helpful to wet the finger befor putting a gp lens in?

Back 51

Yes but don't have to wet a finger for soft lenses

Front 52

How often and how is a contact lens case cleaned?

Back 52

Scrub with a toothbrush and soap atleast once a week

Front 53

How often should a soft contact be cleaned with an enzyme and what needs to be done after its cleaned?

Back 53

Twice per month, rinse with saline and disinfectant before insertion

Front 54

Should contacts be removed for air tonometer?

Back 54

Yes

Front 55

Should contacts be removed during a vf?

Back 55

No

Front 56

True or false? The zone of flare is always opposite of the displacement of lens?

Back 56

True

Front 57

If a keratometer can't read a steep cornea what can be attached?

Back 57

INNS extension disc