Chapter 8

Question 1

The diameter of a soft lens should be at least ______the corneal diameter.

Answer 1

1mm larger than

Question 2

Giant papillary conjunctivitis (GPC) in soft lens wearers is associated:

Answer 2

Surface deposits

Question 3

A certain brand of soft lens is available in base curves of 8.0, 8.3, and 8.6mm, and a diameter of 14.0mm. Which base curve should be selected first for evaluation on a patient with small, steep eyes?

Answer 3

8.3

Question 4

On the first follow-up visit, a patient cannot see as well as they did one week earlier upon delivery of the lenses. Which of the following is the LEAST likely cause?
a)lenses are the wrong power b) lenses are inverted c) lenses are soiled d) lenses are switched

Answer 4

wrong power

Question 5

The recommended lens/cornea relationship when fitting soft lenses is:
a) corneal alignment
b) mean of the mean
c) three point touch
d) apical clearance

Answer 5

c) three point touch

Question 6

A soft lens with a visibility tint absorbs how much light?
a) < 10% b) 10-20%
c) 40-60% d) > 90%

Answer 6

a) <10%

Question 7

The recommended time for allowing soft lenses to equilibrate on the eye before evaluation is at least ____ minutes.

Answer 7

20

Question 8

Soft lenses should be inserted:

Answer 8

on the inferior sclera

Question 9

Which of the following soft lens parameters CANNOT be specified by the contact lens technician:
a) power b) diameter
c) center thickness d) base curve

Answer 9

center thickness

Question 10

Which of the following conditions is LEAST suitable to soft lens wear?
a) wide palpebral fissure
b) dusty environment
c) moderate corneal astigmatism
d) dry environment

Answer 10

Dusty environment

Question 11

Which of the following instruments is most beneficial in verifying three point touch?

Answer 11

keratometer

Question 12

Most soft lenses should fit with ____ movement upon blinking?

Answer 12

> 1mm

Question 13

Spectacle Rx +4.12 +0.75 x 90, K’s 44.50 @180/44.87 @90, VD=13mm. What power soft lens would be expected to give the best correction?

Answer 13

+4.50

Question 14

Which of the following is NOT necessary for a successful soft lens fit?
a) perfect centration
b) three point touch
c) adequate movement
d) patient comfort

Answer 14

a) perfect centration

Question 15

It is advisable to always fit the ___ soft lens that meets all fitting criteria.
a) strongest b) weakest

Answer 15

a) strongest

Question 16

Gently bending a soft lens to make sure it is not inside out before insertion is called the ____ test.

Answer 16

Taco

Question 17

Which two lens parameters determine the sagittal depth of the lens?

Answer 17

diameter, base curve

Question 18

Which of the following is experienced by most soft lens wearers?
a) poor vision b) lens dryness
c) neovascularization d) superficial punctate keratitis

Answer 18

b) lens dryness

Question 19

Which instrument is LEAST likely to be used for in-office verification of soft lenses?
a) radiuscope b) lensometer
c) slit lamp d) measuring magnifier

Answer 19

a) radiuscope