NCLE Prep Exam 3 of 4 Questions and Answers 100%
Solved
The profile analyzer evaluates the peripheral curve blends and the radiuscope measures the
base curve of the rigid contact lens. The measuring magnifier is the only instrument that will
measure the parameters listed.
Assessment of the quality of the peripheral curves (blends) of a rigid contact lens is
achievable
by the use of the:
A. Profile analyzer
B. Shadowgraph
C. Profile analyzer
D. Burton lamp -Answer A. Profile analyzer
All of the listed instruments show that a rigid contact lens has blends. However, the only
instrument that can adequately assess the quality of the blends between the peripheral
posterior curve (PPC), intermediate posterior curve (IPC) and the central posterior curve
(CPC),
is the profile analyzer.
The instrumental used for magnification of the edge of a rigid contact lens is a:
,A. Keratometer
B. Shadowgraph
C. Profile analyzer
D. V-groove gauge -Answer B. Shadowgraph
A keratometer measures the corneal curvature. A profile analyzer measures the peripheral
curves (blends) and a v-groove gauge measures the diameter of a rigid contact lens.
The tolerance for lens power under +/-10.00D is:
A. 0.12D
B. 0.25D
C. 0.37D
D. 0.50D -Answer A. 0.12D
According to the ANSI standards (Z80.2 - 1989), the tolerance for the power of a contact lens
under +/-10.00D is +/-0.12D
Which of the following will NOT measure contact lens parameters?
A. Keratometer
B. Radiuscope
C. Burton lamp
, D. Thickness gauge -Answer A keratometer will measure the base curve of a lens with an
attachment known as a con-ta-check; however, a radiuscope is most frequently used. A
thickness gauge will measure the center thickness of a contact lens. A burton lamp evaluates
the fluorescein pattern similar to a slit lamp.
A warped lens will show ________ base curve(s) on the radiuscope and a ________ power on
the lensometer.
A. One / sphero-cylindrical
B. Two / sphero-cylindrical
C. One / sphero-cylindrical
D. Two / spherical -Answer D. Two / spherical
Verification should show the following:
Lens type - Radiuscope - Lensometer
Spherical - One base curve - Spherical Rx
Warped - two base curves - spherical rx
Front toric - one base curves - sphero-cylindrical rx
Back toric - two base curves - sphero-cylindrical rx
Bi-toric - two base curves - sphero-cylindrical rx
Solved
The profile analyzer evaluates the peripheral curve blends and the radiuscope measures the
base curve of the rigid contact lens. The measuring magnifier is the only instrument that will
measure the parameters listed.
Assessment of the quality of the peripheral curves (blends) of a rigid contact lens is
achievable
by the use of the:
A. Profile analyzer
B. Shadowgraph
C. Profile analyzer
D. Burton lamp -Answer A. Profile analyzer
All of the listed instruments show that a rigid contact lens has blends. However, the only
instrument that can adequately assess the quality of the blends between the peripheral
posterior curve (PPC), intermediate posterior curve (IPC) and the central posterior curve
(CPC),
is the profile analyzer.
The instrumental used for magnification of the edge of a rigid contact lens is a:
,A. Keratometer
B. Shadowgraph
C. Profile analyzer
D. V-groove gauge -Answer B. Shadowgraph
A keratometer measures the corneal curvature. A profile analyzer measures the peripheral
curves (blends) and a v-groove gauge measures the diameter of a rigid contact lens.
The tolerance for lens power under +/-10.00D is:
A. 0.12D
B. 0.25D
C. 0.37D
D. 0.50D -Answer A. 0.12D
According to the ANSI standards (Z80.2 - 1989), the tolerance for the power of a contact lens
under +/-10.00D is +/-0.12D
Which of the following will NOT measure contact lens parameters?
A. Keratometer
B. Radiuscope
C. Burton lamp
, D. Thickness gauge -Answer A keratometer will measure the base curve of a lens with an
attachment known as a con-ta-check; however, a radiuscope is most frequently used. A
thickness gauge will measure the center thickness of a contact lens. A burton lamp evaluates
the fluorescein pattern similar to a slit lamp.
A warped lens will show ________ base curve(s) on the radiuscope and a ________ power on
the lensometer.
A. One / sphero-cylindrical
B. Two / sphero-cylindrical
C. One / sphero-cylindrical
D. Two / spherical -Answer D. Two / spherical
Verification should show the following:
Lens type - Radiuscope - Lensometer
Spherical - One base curve - Spherical Rx
Warped - two base curves - spherical rx
Front toric - one base curves - sphero-cylindrical rx
Back toric - two base curves - sphero-cylindrical rx
Bi-toric - two base curves - sphero-cylindrical rx
