Sam's Club NCLE Flashcards
The base curve of a rigid gas permeable contact lens must be verified to be within ______ of that specified.
A. -+ .50mm
B. -+ .25mm
C. -+ .0.2mm
D. -+ 0.05mm
D. -+ 0.05mm
A PMMA rigid lens wearer returns to the office for follow-up keratometry. The readings obtained at this time should be within ______________ of the original readings
A. -+.50 D
B. -+1.00 D
C. .30mm
D. None of the above
A. -+.50 D
Which of the following modifications can be made to a rigid lens ?
A. Adding minus power
B. Removing Scratches from the surface
C. Flattening the peripheral curves
D. All of the above
D. All of the above
It is possible to reduce the diameter of a rigid contact lens through the use of:
A. The file technique
B. The Razor Blade Technique
C. An abrasive stone
D. All of the above
D. All of the above
The thickness of a contact lens may be verified with a
A. Lens Clock
B. Con-ta-chek
C. Diameter Gauge
D. Thickness gauge
D. Thickness gauge
A-6.50 PMMA lens measures 8.6mm in diameter and is found to be fitting high because of attachment to the upper lid. Which of the following modifications could improve this ?
A. Increase the Size of the lens
B. Add Minus Power
C. Reduce the edge thickness
D. None of the above
C. Reduce the edge thickness
Which of the following power modifications may be most easily performed ?
A. Adding Plus Power
B. Adding Minus Power
C. Adding Cylinder
D. Adding Prism Power
B. Adding Minus Power
Which of the following modifications are possible to perform on a RGP lens?
A. Steepen the peripheral Curves
B. Blend the transition zone
C. Flatten the secondary curve
D. Reduce the diameter of the optical zone.
A. Steepen the peripheral Curves
One purpose of grinding a posterior intermediate curve onto a rigid contact lens would be to:
A. Taper the edge
B. Tighten the fit
C. loosen the fit
D. Reduce the diameter
C. loosen the fit
Wetting solutions serve all of the following functions except:
A. Cleans the lens after they are removed from the eye.
B. Provides lubrication between the lens surface and the lid
C. Provides a protective coating over the surface so that it does not come in contact with the finger during lens insertion.
D. Converts the hydrophobic lens surface into a hydrophilic surface.
A. Cleans the lens after they are removed from the eye.
A soaking solution will perform each of the following functions except:
A. It will prevent eye infections form a contaminated lens
B. It will aid in cleaning he lens after removal
C. It helps to maintain the lens in a state of hydrated equilibrium
D. It Permits the lens to float freely when not being worn.
A. It will prevent eye infections form a contaminated lens
