(NUMBER 22)
Given the following information:
K's 45.00 @ 180/42.00 @ 90
Rx -2.00 -4.25 x 90
Which of the following RGP lens designs would best correct this wearers vision?
a. 45.00 -2.00
b. 42.00 -2.00 -4.25 x 90 prism ballasted
c. 42.00 -2.00
d. 42.00/45.00 -2.00 - ANS-d. 42.00/45.00 -2.00
A _________ lens is a translating bifocal:
a. concentric
b. aspheric
c. deffractive
d. segmented - ANS-d. segmented
A ________auxiliary trial lens will extend the keratometer to 61.00 D.
a. -1.25
b. +1.25
c. -1.50
d. +1.50 - ANS-b. +1.25
A back toric soft lens works best with:
a. Residual astigmatism
b. high toricity of the cornea c. Low corneal toricity
d. Spherical toricity - ANS-b. high toricity of the cornea A bifocal lens is one whose power
shifts from the center to the periphery of the lens. a. an aspherical lens
b. a tangent streak lens
c. a monocentric lens
d. a crescent lens - ANS-a. an aspherical lens
The term "dense white" on the entire peripheral circumference of the cornea that does not stain
is known as and is frequently observed in elderly patients: a. new blood vessels b. Dellen
c. The senilus arcus d. Corneal ulcer - ANS-c. Arcus senilus
A good illustration of a bifocal contact lens that can rotate without impairing vision is: a.
aspheric
b. executive
c. fused crescent
d. tangent streak - ANS-d. tangent streak
a hardening of the crystalline lens causing loss of accommodation is known as:
a. presbyopia
b. myopia
c. hyperopia
, d. aphakia - ANS-a. presbyopia
A high degree of with the rule astigmatism fitted with a rigid spherical lens will show touch
a. on the horizontal meridian
b. on the vertical meridian
c. on the oblique meridian
d. on the horizontal meridian and the residual meridian - ANS-a A lens fitted for keratoconus
should:
a. Flatten the apex
b. Aspire high. c. Align the apex
d. Ride low - ANS-c. Align the apex
A low riding high plus on a 40.00/40.75 cornea could be corrected with
a. a myoflange
b. a hyperflange
c. a one cut
d. a panafocal - ANS-a. a myoflange
A dry RGP lens may result in: a. hazy, filmy vision
b. lens awareness
c. dryness or grittiness
d. all of the above - ANS-d. all of the above
A normal fitting soft contact lens will have:
a. three point touch (apex and periphery)
b. apical clearance
c. edge stand-off
d. none of the above - ANS-a. three point touch (apex and periphery)
A typical time to break up a tear is a. 6-7 seconds
b. 10-12 seconds
c. In less than five seconds d. none of the preceding - ANS-b. 10 to 12 seconds A rigid contact
lens measures +15.00 BVP. The FVP will measure.
a. a lesser dioptric reading
b. an increase in the dioptric reading c. an identical dioptric reading
d. a reading that is astigmatic - ANS-a. a reading that is less dioptric A rigid lens showing a
band-shaped area of touch on the flattest meridian is an indication of
a. tight fit b. an alignment fit
c. a flat fit
d. an astigmatic fit - ANS-a. steep fit
A rigid lens showing apical pooling is an indication of
a. steep fit
b. an alignment fit
c. a straight fit d. an astigmatic fit - ANS-a. steep fit
A rigid lens showing apical vaulting is an indication of
a. tight fit b. an alignment fit
c. a straight fit d. a steep fit due to astigmatism (ANS-a) A rigid lens showing no apical
clearance is an indication of
a. a steep fit