Contact Lens 2.0

Question 1

In contact lenses each 0.5 mm radius is equivalent to about ______ D.

Answer 1

2.5

Question 2

A front toric contact lens is indicated primarily for?

Answer 2

Lenticular astigmatism

Question 3

Which layer of the tear film helps to retard evaporation?

Answer 3

Lipid

Question 4

A contraindication for fitting contact lenses is:

Answer 4

Keratitis sicca (dry eye where cornea is inflamed)

Question 5

A property of plastic which is a disadvantage for its use in contact lenses is:

Answer 5

Hydrophobic

Question 6

The space between the upper and lower lids is called the:

Answer 6

Palprebral fissure

Question 7

A monocular complaint with a contact lens is most likely due to:

Answer 7

Poor edge

Question 8

Poor vision with glasses after contact lenses have been removed is called?

Answer 8

Spectacle blur

Question 9

All contact lens modifications tend to:

Answer 9

Loosen the lens fit

Question 10

If the base curve of a contact lens is 45.00 D, the posterior peripheral curve would be about:

Answer 10

26.00 D (peripheral curve on a rigid contact lens is about 20.00 D flatter than the base)

Question 11

A rigid lens showing apical pooling indicates:

Answer 11

Tight fit

Question 12

The optic spherometer verifies primarily what contact lens parameter?

Answer 12

Base curve (another name for radiuscope)

Question 13

Arc staining occurs primarily because of:

Answer 13

Sharp juncture between the blends

Question 14

A localized area of corneal thinning usually at the limbus caused by excessive dehydration is called a :

Answer 14

Dellen

Question 15

What is a veruccae?

Answer 15

Benign eye lid tumor

Question 16

What is a arcus senilus?

Answer 16

Grey band at the limbus in many older people

Question 17

The chemist who invented HEMA is:

Answer 17

Wichterle

Question 18

Tears on the front of a contact lens is called?

Answer 18

The pre-corneal film

Question 19

The largest layer of the cornea is:

Answer 19

Stroma

Question 20

What will enhance the viewing of neo-vascularity/

Answer 20

Red free filter

Question 21

If a profile analyzer is not available to evaluate the blend quality of a rigid lens, what else can be used?

Answer 21

Overhead fluorrescent tubes

Question 22

A mosaic pattern observed on the cornea with fluorescein might be from:

Answer 22

Eyelid rubbing

Question 23

Which of the following rigid lens parameters is not under the control of the fitter?
A:posterior radius B. Peripheral Posterior Curve C. Intermediate Posterior Curve D. Central Anterior curve E. CN Bevel

Answer 23

D

Question 24

A grayish band that surrounds the cornea in some people is called the?

Answer 24

arcus senilis

Question 25

The index of refraction of the cornea is:

Answer 25

1.37

Question 26

The index of refraction of the aqueous or vitreous is:

Answer 26

1.33

Question 27

The index of refraction of PMMA is :

Answer 27

1.49

Question 28

The index of refraction of crown glass is:

Answer 28

1.523

Question 29

The index of refraction of many soft lenses is:

Answer 29

1.43

Question 30

Corneal inflammation due to a tear deficiency is:

Answer 30

Keratitis Sicca

Question 31

Devitalized cells stain with?

Answer 31

Rose Bengal

Question 32

The keartometer interprets the cornea as:

Answer 32

A sphere and a small convex mirror

Question 33

The optic zone of most corneas is between:

Answer 33

5.8-6.2 mm

Question 34

What is the typical adjustment period for a new RGP wearer?

Answer 34

1-2 weeks

Question 35

When fitting monovision contact lenses the near eye is usually:

Answer 35

The non dominant eye and given as little ADD as possible

Question 36

A disease commonly associated with a tear deficiency is

Answer 36

Rheumatoid arthritis

Question 37

What slit-lamp illumination is used to verify tear break up time (TBUT)?

Answer 37

Diffuse

Question 38

The following ametropia frequently results in high riding lenses:

Answer 38

-12.00

Question 39

Corneal sensitivity is usually reduced when:

Answer 39

After cataract surgery

Question 40

A topogometer is an attachment to the?

Answer 40

the ophthalmometer (AKA keratometer)

Question 41

A Burton lamp is:

Answer 41

Used to evaluat fluorescein patterns (a hand held device)

Question 42

Soft lenses should be inserted:

Answer 42

On the inferior sclera

Question 43

Agents that destroy, neutralize or inhibit growth of pathogenic organisms on contact lenses are called?

Answer 43

Preservatives

Question 44

Which slit lamp illumination can be done without the aid of the microscope?

Answer 44

Sclerotic Scatter

Question 45

Oxygen is delivered to the cornea by the?

Answer 45

Precorneal film

Question 46

The bacteria killing ingredient found in the tear film is:

Answer 46

Lysozyme

Question 47

What is usually ground on a minus rigid contact lens when lenticulation is not necessary?

Answer 47

CN bevel

Question 48

What modification cannot be performed on a rigid contact lens?

Answer 48

Make the peripheral curves steeper

Question 49

Transient keratometric mire distortion is usually due to?

Answer 49

Pre-ocular tear film

Question 50

Development of new blodd vessels in the cornea is called?

Answer 50

Neovascularization

Question 51

A rigid lens showing apical touch indicates a fit that is?

Answer 51

Flat