NCLE Advanced Certification Exam// IAHSS
ADVANCED OFFICER CERTIFICATIONS EXAMS
|ACCURATE TESTING VERSIONS
while others may be introduced to the lens surface by way of the patient's hands or tear film.
Preservatives in care systems such as sorbic acid or potassium sorbate can cause lenses to discolor.
Environmental contaminants such as make-up, newsprint and nicotine, can also discolor a soft contact
lens. - ANSWER-72. Soft contact lenses may be discolored from coming in contact with many
contaminants. Whid of the following would not discolor a soft cont act lens?
A. Make-up
B. Newsprint
C. Nicotine
D. Hydrogen peroxide
The answer is D.
In cases of bullous keratopathy, nystagmus and against the rule astigmatism, the patient will do quite
well with a soft contact lens. In cases of bullous keratopathy, a soft lens may even be used as a bandage
to improve the patient's comfort. In nystagmus, the patient is often more comfortable with a soft lens
physically and visually due to the rapid eye movements characteristic of that condition. Many
practitioners prefer to fit soft lenses on patients whose astigmatism is against the rule since a rigid lens
may tend to displace laterally in that situation. However, in cases of irregular astigmatism, the most
appropriate option for the patient is a rigid lens material. - ANSWER-73. A soft contact lens can be
successfully used in each of the following cases except:
A. Bullous keratopathy
B. Nystagmus
C. Against the rule astigmatism
,D. Irregular astigmatism
The answer is B.
With advances in manufacturing, disposables have become more affordable, more reproducible and are
an extremely effective solution to the problem of GPC and heavy deposits. Extended wear of lenses will
only increase the problem of deposits and GPC. CAB (cellulose acrylate butyrate) is a rigid gas permeable
material. - ANSWER-74. The major concern in using silicone as a contact lens material is it's?
A. Hydrophilic nature
B. Optics
C. Hydrophobic nature
D. Oxygen transmission
The answer is A.
When manufacturing soft lenses by spin casting, the speed and amount of liquid monomer determine
the thickness and power of each lens. The power curve is located on the back surface; the front surface
remains constant regardless of lens power. - ANSWER-75. Which method of manufacturing uses
centrifugal force of a known speed to spin liquid monomer in a bowl?
A. Spin casting
B. Cast molding
C. Lathe cutting
D. Hydro molding
The answer is C.
,Lathe cutting of soft contact lenses is done with the lens material in the dehydrated state. The CPC
(central posterior curve) is cut first on the back side. The anterior surface is the power curve, and is cut
after the CPC. - ANSWER-76. Which method of manufacturing soft lenses is done with the material in a
dehydrated state while the curves are produced on both sides?
A. Spin casting
B. Cast molding
C. Lathe cutting
D. Hydro molding
The answer is B.
The posterior optical zone will directly affect the lens to cornea relationship of a rigid gas permeable
lens. If the posterior optical zone is steepened, it will increase the sagittal depth. If it is flattened, it will
decrease the sagittal depth. Changing the power, which is accomplished by changing the anterior optical
zone, will not affect the sagittal depth of the lens, nor will changing its edge design. - ANSWER-1. The
sagittal depth of a rigid gas permeable contact lens can be altered without changing the diameter by:
A. Changing the power
B. Changing the edge design
C. Changing the radius of curvature of the anterior optical zone
D. Changing the radius of curvature of the posterior optical zone
The answer is A.
A lens is truncated by removing a segment of the lower edge of a contact lens. This creates a straight
edge that interacts with the lower lid and aids in lens positioning. Of the lens designs listed in the
question, the only one that requires precise positioning of its optical portions is a translating bifocal lens.
- ANSWER-2. A truncation is used on a rigid gas permeable contact lens to help enhance the
performance of which type of design?
, A. Bifocal
B. Aphakic
C. Bitoric
D. Keratoconus
The answer is B.
A lenticular or myoflange design will decrease the mass of an aphakic lens as well as increase the edge
profile, which allows it to interact more with the upper lid and aid in positioning of the lens. - ANSWER-
3. The mass of an aphakic rigid gas permeable contact lens can be reduced by making the lens design:
A. Spherical
B. Lenticular
C. Tricurve
D. Aspheric
The answer is B.
Increasing the optical zone diameter and increasing the overall lens diameter will both tighten and
steepen the relationship of the lens to the cornea. Decreasing the optic zone diameter will serve to
flatten and loosen the lens to cornea relationship. Using a prism-ballasted lens design will not affect the
lens to cornea relationship as it relates to sagittal depth. - ANSWER-4. In order to tighten the fit of a rigid
gas permeable lens you can:
I. Increase the optical zone diameter
2. Decrease the optical zone diameter
3. Increase the overall lens diameter
4. Use a prism ballasted lens design
ADVANCED OFFICER CERTIFICATIONS EXAMS
|ACCURATE TESTING VERSIONS
while others may be introduced to the lens surface by way of the patient's hands or tear film.
Preservatives in care systems such as sorbic acid or potassium sorbate can cause lenses to discolor.
Environmental contaminants such as make-up, newsprint and nicotine, can also discolor a soft contact
lens. - ANSWER-72. Soft contact lenses may be discolored from coming in contact with many
contaminants. Whid of the following would not discolor a soft cont act lens?
A. Make-up
B. Newsprint
C. Nicotine
D. Hydrogen peroxide
The answer is D.
In cases of bullous keratopathy, nystagmus and against the rule astigmatism, the patient will do quite
well with a soft contact lens. In cases of bullous keratopathy, a soft lens may even be used as a bandage
to improve the patient's comfort. In nystagmus, the patient is often more comfortable with a soft lens
physically and visually due to the rapid eye movements characteristic of that condition. Many
practitioners prefer to fit soft lenses on patients whose astigmatism is against the rule since a rigid lens
may tend to displace laterally in that situation. However, in cases of irregular astigmatism, the most
appropriate option for the patient is a rigid lens material. - ANSWER-73. A soft contact lens can be
successfully used in each of the following cases except:
A. Bullous keratopathy
B. Nystagmus
C. Against the rule astigmatism
,D. Irregular astigmatism
The answer is B.
With advances in manufacturing, disposables have become more affordable, more reproducible and are
an extremely effective solution to the problem of GPC and heavy deposits. Extended wear of lenses will
only increase the problem of deposits and GPC. CAB (cellulose acrylate butyrate) is a rigid gas permeable
material. - ANSWER-74. The major concern in using silicone as a contact lens material is it's?
A. Hydrophilic nature
B. Optics
C. Hydrophobic nature
D. Oxygen transmission
The answer is A.
When manufacturing soft lenses by spin casting, the speed and amount of liquid monomer determine
the thickness and power of each lens. The power curve is located on the back surface; the front surface
remains constant regardless of lens power. - ANSWER-75. Which method of manufacturing uses
centrifugal force of a known speed to spin liquid monomer in a bowl?
A. Spin casting
B. Cast molding
C. Lathe cutting
D. Hydro molding
The answer is C.
,Lathe cutting of soft contact lenses is done with the lens material in the dehydrated state. The CPC
(central posterior curve) is cut first on the back side. The anterior surface is the power curve, and is cut
after the CPC. - ANSWER-76. Which method of manufacturing soft lenses is done with the material in a
dehydrated state while the curves are produced on both sides?
A. Spin casting
B. Cast molding
C. Lathe cutting
D. Hydro molding
The answer is B.
The posterior optical zone will directly affect the lens to cornea relationship of a rigid gas permeable
lens. If the posterior optical zone is steepened, it will increase the sagittal depth. If it is flattened, it will
decrease the sagittal depth. Changing the power, which is accomplished by changing the anterior optical
zone, will not affect the sagittal depth of the lens, nor will changing its edge design. - ANSWER-1. The
sagittal depth of a rigid gas permeable contact lens can be altered without changing the diameter by:
A. Changing the power
B. Changing the edge design
C. Changing the radius of curvature of the anterior optical zone
D. Changing the radius of curvature of the posterior optical zone
The answer is A.
A lens is truncated by removing a segment of the lower edge of a contact lens. This creates a straight
edge that interacts with the lower lid and aids in lens positioning. Of the lens designs listed in the
question, the only one that requires precise positioning of its optical portions is a translating bifocal lens.
- ANSWER-2. A truncation is used on a rigid gas permeable contact lens to help enhance the
performance of which type of design?
, A. Bifocal
B. Aphakic
C. Bitoric
D. Keratoconus
The answer is B.
A lenticular or myoflange design will decrease the mass of an aphakic lens as well as increase the edge
profile, which allows it to interact more with the upper lid and aid in positioning of the lens. - ANSWER-
3. The mass of an aphakic rigid gas permeable contact lens can be reduced by making the lens design:
A. Spherical
B. Lenticular
C. Tricurve
D. Aspheric
The answer is B.
Increasing the optical zone diameter and increasing the overall lens diameter will both tighten and
steepen the relationship of the lens to the cornea. Decreasing the optic zone diameter will serve to
flatten and loosen the lens to cornea relationship. Using a prism-ballasted lens design will not affect the
lens to cornea relationship as it relates to sagittal depth. - ANSWER-4. In order to tighten the fit of a rigid
gas permeable lens you can:
I. Increase the optical zone diameter
2. Decrease the optical zone diameter
3. Increase the overall lens diameter
4. Use a prism ballasted lens design
