NAO TEST 4 100 2026 SCRIPT COMPLETE
SOLUTIONS
◉ Corneal Contact lenses:
Are a typical soft contact lens design
Bridge the limbus and some of the sclera
Are last resort contact lenses
Are common designs for rigid and gas perm contacts. Answer: Are
common designs for rigid and gas perm contacts
◉ The majority of soft lenses fit today are:
Corneal
Hapatic
Semi scleral
Hydrophobic. Answer: Semi scleral
◉ A liquid coming in contact with a hydrophilic lens material with a
relatively small wetting angle would be likely to:
Form beads on the surface
Quickly evaporate
Spread evenly over the surface
None of the above. Answer: Spread evenly over the surface
,◉ A contact lens with a diameter larger than that of the cornea is
called a ____ lens.
Corneal
Hydrophilic
Hydrophobic
Hapatic. Answer: Hapatic
◉ All of the following are symptoms of a loose fitting lens except:
Constant awareness
Lid sensation
Burning
None of the above. Answer: Burning
◉ Of those curves listed, which indicates the flattest base curve?
7.5 mm
37.50 D
8.6 mm
49.00 D. Answer: 37.50 D
,◉ A contact lens was ordered with a base curve of 7.85 mm but was
received back from the lab with a base curve of 7.80 mm. The base
cure of the actual lens is:
0.25 D flatter
0.25 D steeper
0.50 D flatter
0.50 D steeper. Answer: 0.25 D steeper
◉ It is noticed that a rigid CL containing a base curve of 7.42mm is
fitting quite loose. A tighter fit may be achieved by changing the B.C.
to:
7.46 mm
7.85 mm
8.04 mm
None of the above. Answer: None of the above
◉ A CL has a B.C. of 7.50 mm. Its posterior peripheral curve would
most likely be:
7.45 mm
42.50 D
75.35 mm
30.00 D. Answer: 42.50 D
, ◉ The secondary curve of a rigid contact lens generally:
Is steeper than the CPC (Central posterior curve)
1-2 D flatter than CPC
2-4 D flatter than CPC
None of the above. Answer: 2-4 D flatter than CPC
◉ The term "hapaptic lens" is used in reference to:
Prism ballast
Truncated
Scleral
Spin cast. Answer: Scleral lens
◉ The CPC of a CL measures 7.5 mm radius of curvature. Its power
in diopters is:
41.00 D
42.00 D
45.00 D
47.00 D`. Answer: 45.00 D
◉ The fitting characteristics of a gas permeable rigid CL may be
altered by:
Changing the CPC's radius of curvature
SOLUTIONS
◉ Corneal Contact lenses:
Are a typical soft contact lens design
Bridge the limbus and some of the sclera
Are last resort contact lenses
Are common designs for rigid and gas perm contacts. Answer: Are
common designs for rigid and gas perm contacts
◉ The majority of soft lenses fit today are:
Corneal
Hapatic
Semi scleral
Hydrophobic. Answer: Semi scleral
◉ A liquid coming in contact with a hydrophilic lens material with a
relatively small wetting angle would be likely to:
Form beads on the surface
Quickly evaporate
Spread evenly over the surface
None of the above. Answer: Spread evenly over the surface
,◉ A contact lens with a diameter larger than that of the cornea is
called a ____ lens.
Corneal
Hydrophilic
Hydrophobic
Hapatic. Answer: Hapatic
◉ All of the following are symptoms of a loose fitting lens except:
Constant awareness
Lid sensation
Burning
None of the above. Answer: Burning
◉ Of those curves listed, which indicates the flattest base curve?
7.5 mm
37.50 D
8.6 mm
49.00 D. Answer: 37.50 D
,◉ A contact lens was ordered with a base curve of 7.85 mm but was
received back from the lab with a base curve of 7.80 mm. The base
cure of the actual lens is:
0.25 D flatter
0.25 D steeper
0.50 D flatter
0.50 D steeper. Answer: 0.25 D steeper
◉ It is noticed that a rigid CL containing a base curve of 7.42mm is
fitting quite loose. A tighter fit may be achieved by changing the B.C.
to:
7.46 mm
7.85 mm
8.04 mm
None of the above. Answer: None of the above
◉ A CL has a B.C. of 7.50 mm. Its posterior peripheral curve would
most likely be:
7.45 mm
42.50 D
75.35 mm
30.00 D. Answer: 42.50 D
, ◉ The secondary curve of a rigid contact lens generally:
Is steeper than the CPC (Central posterior curve)
1-2 D flatter than CPC
2-4 D flatter than CPC
None of the above. Answer: 2-4 D flatter than CPC
◉ The term "hapaptic lens" is used in reference to:
Prism ballast
Truncated
Scleral
Spin cast. Answer: Scleral lens
◉ The CPC of a CL measures 7.5 mm radius of curvature. Its power
in diopters is:
41.00 D
42.00 D
45.00 D
47.00 D`. Answer: 45.00 D
◉ The fitting characteristics of a gas permeable rigid CL may be
altered by:
Changing the CPC's radius of curvature
