Fortnightly Quiz 5

This quiz has been expired, Answer key is given below

Question 1 of 20

Which of the following is FALSE about corneal warpage regarding CL:

A it refers to a change in the corneal curvature associated with contact lens wear
B corneal oedema is a feature
C it is a reversible condition
D it interferes with the result of biometry

Question 2 of 20

A contact lens wearer complains that his vision is blurred immediately after blinking. Slit lamp examination reveals excessive movement. To reduce the movement, you may:

A increase the oxygen permeability of the contact lens
B decrease the diameter of the contact lens
C increase the thickness of the contact lens
D reduce the wearing time

Question 3 of 20

The minimum percentage of oxygen required to avoid corneal swelling in the closed eye situation is considered to be:

A 10%
B 15%
C 18%
D 21%

Question 4 of 20

In currently available hydrogel contact lenses, increasing the water content:

A decreases the refractive index
B increases the refractive index
C has no effect on the refractive index
D increases lens tensile strength

Question 5 of 20

Which ocular disorder would demonstrate congenital nystagmus, photophobia, decreased acuity and iris transillumination?

A Albinism
B Aniridia
C Rod monochromatism
D Cone monochromatism

Question 6 of 20

Which ocular disorder in its advanced stages would respond best to minification?

A ROP
B Retinal dystrophy
C ARMD
D Glaucoma

Question 7 of 20

Distance devices that may help the low vision patient include all EXCEPT

A field awareness system
B absorptive lens and coatings
C Microscope
D Pinhole lens

Question 8 of 20

Accurate way of describing the conclusion of X chrome lens is

A All lens wearers are able to achieve “normal” colour vision.
B Many lens wearers appear to appreciate an improvement in colour perception and vividness
C The lenses should be used binocularly to achieve any colour vision improvement.
D It is expected that these lenses appear to improve colour perception in dim illumination.

Question 9 of 20

A patient has a best corrected near acuity of 0.33/4M and desires to read a newspaper of 1M print. What reading cap will be required for a 3x telescope to accomp lish this task?

A plus 5.51D
B plus 3.01D
C plus 4.04D
D plus 6.04D

Question 10 of 20

What is the accommodative amplitude of a patient with a far point 20 cm behind the eye and a near point at infinity?

A 5 D
B 1 D
C 4 D
D 2.5 D

Question 11 of 20

What reading add is needed to his corrected distance prescription so that at 40 cm this patient uses half of his accommodative amplitude?

A plus 2.50D
B plus 1.75D
C plus 2D
D No reading add needed

Question 12 of 20

When looking at an object at 25 cm, a patient has an esotropia of 30prism. With + 3.00 D glasses, his esotropia decreases to 15prism. What is his distance esodeviation without glasses?

A 6 prism D
B 10 prism D
C 18 prism D
D 36 prism D

Question 13 of 20

A Galilean telescope is constructed with a +5.00 D objective and a - 10.00 D eyepiece. What is the magnification of this telescope?

A ½×
B 50×
C 2×
D 5×

Question 14 of 20

You have a +10 D lens and a +20 D lens. You want to make a 2× magnifier. What is the distance between the lenses to produce this magnification?

A 10 cm
B 15 cm
C 5 cm
D 25 cm

Question 15 of 20

How much accommodation is required to view an object 1 m in front of the + 10 D lens?

A 2 D
B 10 D
C 5 D
D 8 D

Question 16 of 20

Prescription swimming goggles are constructed from plastic (n = 1.45) planoconcave lenses. They measure -2.00 D in air. What is the power of the goggles when worn underwater (nwater = 1.33)?

A -1.50 D
B -2.25 D
C -2.00 D
D -3.33 D

Question 17 of 20

A phakic patient undergoes a vitrectomy with replacement of his vitreous fluid (n = 1.34) with silicone oil (n= 1.40). What change occurs in his prescription?

A Myopic shift
B Hyperopic shift
C No significant change in prescription
D Cannot be determined with the information given

Question 18 of 20

You use the duochrome test to refine the refraction of a patient. The patient says the red letters are much clearer than the green letters. The patient:

A Is overplussed
B Is overminused
C is anisometropic
D is presbyopic

Question 19 of 20

You hold a +1.00 D lens in front of a patient. At a working distance of 67 cm, you see against motion with the streak oriented at 90° and less against movement with the streak oriented at 180°. Which situation exists for this patient?

A Simple myopic astigmatism
B Compound myopic astigmatism
C Simple hyperopic astigmatism
D Compound hyperopic astigmatism

Question 20 of 20

You perform streak retinoscopy on a cyclopleged infant. With the streak oriented vertically at 90°, you neutralize the reflex with a -2.00 D lens (after subtracting the working distance), and with the horizontal streak, +3.00 D lens. What is the cycloplegic refraction?

A 3.00-2.00 ×180°
B -2.00 + 3.00 × 90°
C -2.00 + 5.00 × 180°
D 3.00 - 5.00 × 180°