NOCE NOCE Contact Lens Fitting and Care 1

Question 1

What does the base curve (BC) of a contact lens refer to?

Accepted Answer

The radius of curvature of the back surface of the lens

Answer

The thickness at the center of the lens

Answer

The total diameter of the lens

Answer

The refractive power of the lens

Question 2

What does the Dk value of a contact lens material represent?

Accepted Answer

Oxygen permeability of the lens material

Answer

Lens durability and scratch resistance

Answer

Refractive index of the lens

Answer

Water content percentage

Question 3

What is the typical overall diameter range for standard soft contact lenses?

Accepted Answer

13.8–14.5 mm

Answer

8.0–9.0 mm

Answer

9.5–10.5 mm

Answer

16.0–17.0 mm

Question 4

Which FDA group classification describes soft contact lens materials with HIGH water content and IONIC charge?

Accepted Answer

Group IV

Answer

Group I

Answer

Group II

Answer

Group III

Question 5

What is the primary function of the pre-lens tear film in contact lens wear?

Accepted Answer

To lubricate the lens surface and maintain optical clarity

Answer

To increase lens oxygen permeability

Answer

To prevent lens dehydration permanently

Answer

To sterilize the contact lens during wear

Question 6

Daily disposable contact lenses are designed to be worn for what maximum duration before disposal?

Accepted Answer

One full day, then discarded

Answer

One hour per day

Answer

One week with nightly removal

Answer

30 days of continuous wear