100 Multiple Choice Questions (MCQS) Optics & refraction.doc

100 Multiple Choice Questions (MCQS) Optics & refraction

1. Select the one that is BEST in each case
1. The spherocylindrical transposition of the crossed cylinder +2.25 x 120
0
with -1.75x30
o
is
which one of the following?
A.+2.25 = +4.00 x 30°
B.+2.25 = -4.00 x 30°
C.+2.25 = -4.00 x 120°
D.-1.75 = +4.00 x 30°
E.-1.75 = -4.00 x 120°
2. A patient reports that during fogging the line from 2 o'clock to 8 o'clock appears sharpest and
darkest. The refractionist should add
A.plus cylinder axis 80°
B.plus cylinder axis 20°
C.minus cylinder axis 100°
D.minus cylinder axis 60°
E.minus cylinder axis 120°
3. A 39 -year -old female diabetic reports pronounced blurring of vision for distance for the past
week. She has never worn glasses. Which of the following would you do?
A.Perform an atropine refraction
B.Manifest patient and-give Rx
C.Send her to her endocrinologist
D.Give temporary glasses
E.Do a stress refraction
4. An eye with an amplitude of accommodation of 3 diopters has a near point of 20 c m. Where
is the far point of t this eye?
A.5 cm behind the eye
B.33-1/3 cm in front of the eye
C.50 cm in front of the eye
D.50 cm behind the eye
E.10 cm behind the eye
5. Using a vertical stenopeic slit, the patient requires +3.00 D sphere to see clearly; using the
slit horizontally, a -4.00 D sphere is required. What is the appropriate spherocylinder
correction?
A.-4.00= +7.00 x 90°
B.-4.00= -7.00 x 90°
C.+3.00= +7.00 x 90°
D.+3.00= -7.00 x 90°
E.+3.00= +7.00 x 180°
6. A +12. 00 D lens at 15 mm from the cornea is to be converted to a contact lens. The power of
the contact lens is
A.+11.50
B.+13.60
C.+14.00
D.+15.90
E.+14.70
1

2. 7. Which one of these lenses has the spherical equivalent of + 1.25 D?
A.0.75 cross cylinder
B.+4.00 = +2.00 x 80°
C.+2.00 = -1.50 x 50°
D. -4.00 = +8.00 x 90°
E.-5.00 = +1.00 x 80°
8. Retinoscopy at 67 cm gives you +3.00 at 120
o
axis and a + 5.00 at 30
o
. The resulting
spherocylinder that you would use for the patient is
A.+3.00 = +5.00 x 30
o

B.+5.00 = +3.00 x 30
o

C.+1.50 = +2.00 x 30
o

D.+5.00 = +2.00 x 120
o

E.+2.00 = +3.00 x 30°
9. You wish to correct a 3.00 diopter myope with a -4.00 sphere lens. Where in front of the eye
should you place this lens?
A.16-2/3 cm
B.10-2/3 cm
C.16-1/3 cm
D.25 mm
E.8-1/3 cm
10. While performing the duochrome test, the patient reports that the letters on the green side
are clearer. What should you do?
A.Add more minus sphere
B.Take away plus sphere
C.Add more plus sphere
D.Add minus cylinder
E.None of these
11. A 20-mm size object is placed 25 cm in front of a +8.00 diopter lens. The linear
magnification is
A.5 X
B.4 X
C.3X
D.2X
E.1X
12. A 40-year-old man with early macular degeneration requires a reading add. What would you
start with if his distance correction is 20/100 and he has 4.5 diopters of accommodation using
Kestenbaum's rule?
A.+2.75
B.+5.00
C.+2.00
D.+1.00
E.+1.50
13. The reason that one cannot view the gonioscopic angle directly is
A.the image is blurred by the cornea at the limbus
B.the limbus is frequently pigmented
C.the cornea is hazy near the angle
D.spherical aberration of the cornea
E.total internal reflection of the cornea
2

3. 14. A scotoma viewed on tangent screen at 2meters is 20 cm in its largest dimension. The size
of the lesion on the retina is
A.4.0 mm
B.2.3 mm
C.1.7 mm
D.17 mm
E.7 cm
15. A 60-year-old patient wearing bifocals has an accommodative amplitude of 1 diopter. He
uses a +2.50 add for near correction. At what distances will he see clearly?
A.40 cm to 100 cm, 100 cm to infinity
B.28.5 cm to 100 cm, 14.5 cm to 28.5 cm
C.100 cm to infinity, 10 cm to 20 cm
D.28.5 cm to 40 cm, 100 cm to infinity
E.None of the above
16. An eye is corrected by a -1.50 with -1.50 x 90°. Without the corrective lens, the image falling
on the retina is best described as a
A.circle of least confusion
B.horizontal line
C.vertical line
D.horizontal oval
E.vertical oval
17. An eye which is corrected with -1.00 x 90° and + 1.00 x 180° can be said to have net
astigmatism
A.against the rule
B.with the rule
C.both against and with the rule
D.whose spherical equivalent is +2.00
E.none of these
18. A person wearing a -12 diopter lens is looking through the lens 5 mm below the optical
center. This induces a prism power of
A.6 prism diopters base up
B.12 prism diopters base down
C.16 prism diopters base down
D.3 prism diopters base up
E.6 prism diopters base down
19. The prism induced when reading 1 cm below the optical centers of the following glasses:
O.D. +3.00= -1.00x90°
O.S. +4.00 = +1.00x180°
A.O.D. 3 ∆ base down, O. S. 5 ∆ base down
B.O.D. 5 ∆ base up, O. S. 3 ∆ base down
C.O.D. 3 ∆ base down, O. S. 5 ∆ base up
D.O.D. 3 ∆ base up, O. S. 5 ∆ base up
E.O.D. 5 ∆ base up, O. S. 5 ∆ base down
3

4. 20. The net amount of prism induced for previous question is
A.1 ∆ base up O. S.
B.2 ∆ base up O. S.
C.1 ∆ base down O. S.
D.2 ∆ base down O. S.
E.none of these
21. in the use of cycloplegic drugs. all are correct EXCE PT thast
A.widely dilated pupils decrease the pupillary aberrations
B.the full cycloplegic refraction cannot be prescribed
C.accommodation is curtailed
D.cycloplegia is helpful in children
E.one generally requires a manifest refraction
22. The most rapid cycloplegia is produced by which of the following drugs?
A.Homatropine
B.Cyclopentolate
C.Tropicamide
D.Atropine
E.Scopolamine
23. An ideal cycloplegic agent should do all the following EXCEPT
A.be rapidly effective
B.cause no adverse reactions
C.cause wide dilatation of the pupil associated with cycloplegia
D.permit prompt recovery to normal accommodation
E.maintain cycloplegia for sufficient time
24. A 50-year-old male has just been given a new reading add. His most likely complaint about
his new glasses will be
A.increased magnification
B.reduced range of near vision
C.increased weight
D.increased bifocal jump
E.increased prism deviation
25. An aphake wearing aphakic glasses will most often notice:
A. barrel distortion
B. pincushion distortion
C. image jump
D. spherical aberration
E. chromatic aberration
26. A myope who can read clearly without glasses at 20 cm and has no accommodative reserve
wishes to read at 80 cm. What glasses would you give him?
A. -1.25
B. +1.25
C. -3.75
D. -3. 50
E. -5.00
4

5. 27. The spherocylindrical formulation of a lens is +3.00 = -4.00 x 180°. It can also be
represented as
A. -1.00= +3.00 x 50°
B. +1.00= -3.00 x 90°
C. -1.00 x 180°, +3.00 x 90°
D. -3.00 x 180°, +1. 00 x 90°
E. -3.00 x 90°, +1. 00 x 180°
28. The following cylindrical lenses +3.00 x 180°, +6.00 x 90° can be expressed also as
A. +6.00= -3.00 x 90°
B. -3.00= +6.00 x 90°
C. +3.00 = +6.00 x 180°
D. +6.00 = +3. 00 x 90°
E. +3.00 = +3. 00 x 90°
29. An eye has an amplitude of accommodation of 4 diopters. The far point of the eye is 100 cm
in front of eye. What is the near point?
A. 25 cm
B. 40 cm
C. 10 cm
D. 20 cm
E. 30 cm
30. A person has an accommodative ability of 3D. He is given a +2.0 add. Through which
distances will he see clearly?
A. 10 cm - 20 cm
B. 20 cm - 30 cm
C. 30 cm - 40 cm
D. 20 cm - 50 cm
E. 30 cm - 50 cm
31. A person has a near point of accommodation (NPA) of 10 cm. He is a one-diopter myope.
What is his amplitude of accommodation?
A. 5 D
B. 6 D
C. 7 D
D. 8 D
E. 9 D
32. The longest acting cycloplegic agent is
A. atropine
B. homatropine
C. eucatropine
D. cyclopentolate
E. tropicamide
33. A person wearing a +14.00 contact lens wants to wear spectacles at 1. 5 cm. What
spectacles would you give him?
A. +10.3
B. +10.7
C. +11.3
D. +11.6
E. +11.9
5

6. 34. The objective when using the cross cylinder for cylinder power refinement is to
A. place the circle of least confusion on the retina
B. reduce the cylinder power
C. move the circle of least confusion to the vitreous
D. collapse the conoid of Sturm
E. move the conoid of Sturm to the retina
35. The "Jack-in-the-box" phenomenon is commonly seen in
A. high myopes
B. myopes with bifocals
C. high hyperopes
D. aphakes with contact lenses
E. aphakes with glasses
36. The "Jack-in-the-box" phenomenon is explained by
A. a roving scotoma
B. the prismatic effect of aphakic spectacles C. spherical aberration
D. chromatic aberration
E. rotational magnification
37. The duochrome test depends on the optical principle that
A. light of different colors move at different speeds
B. different light wavelengths are refracted to a different extent
C. red and green are most easily seen by the human eye
D. the speed of light of different colors is different
E. green light has a longer wavelength than red light
38. Which of the following has the greatest refractive power?
A. Anterior surface of the cornea
B. vitreous
C. Anterior surface of the lens
D. Posterior surface of the lens
E. Posterior surface of the cornea
39. Most corneas are shaped like a/an
A. cut- off sphere
B. cut- off cone
C. toric surface
D. conoid
E. aspheric surface
40. The principle of the stenopeic slit is based on
A. the circle of least confusion
B. the conoid of Sturm
C. horizontal vs. vertical astigmatism
D. the pinhole phenomenon
E. Knapp's rule
41. During accommodation all the following changes occur EXCEPT the
A. pupil contracts
D. anterior chamber shallows
C. lens becomes thinner
D. anterior and posterior surfaces of the lens become convex
E. lens sinks down
6

7. 42. A 3-mm lesion on the retina should be how large on a tangent screen at a distance of 1
meter?
A. 17.6cm
B. 16.9 cm
C. 15.6 cm
D. 19.3 cm
E. 15.4 cm
43. A person is wearing -2.00 sphere O. D. and +2.00 sphere O. S. His glasses were dispensed
with the P.D. of the glasses 1 cm too narrow. What is the induced prism in each eye?
A. 2 diopters base out O. D., 2 diopters base out O. S.
B. 2 diopters base in O. D., 2 diopters base in O. S.
C. 1 diopter base in O. D., 1 diopter base in O. S.
D. 1 diopter base out O. D., 1 diopter base in O. S.
E. 1 diopter base out O. D., 1 diopter base out O. S.
44. In accommodation, a change in which of the following structures is most directly responsible
for functional accommodation?
A. Anterior lens capsule
B. posterior lens capsule
C. Lens position
D. Iris
E. Ciliary body
45. "Image jump" occurs with
A. contact lenses when the eyes arc moving
B. bifocal glasses
C. aphakic distance glasses
D. aphakic near glasses
E. none of these
46. "Image jump" occurs because of
A. the change in induced prism when the visual axis sweeps across the upper edge of the
bifocal segment
B. the change in spherical aberration in the bifocal segment
C. a pantoscopic tilt in the glasses
D. the location of the optical center of the bifocal segment
E. all of these
47. "Image jump can be reduced by
A. moving the optical center of the bifocal segment away from the optical center of the
distance correction
B. changing the axis of the astigmatic correction
C. decentering the optical center of the bifocal segment
D. choosing a bifocal segment that has its optical center at the top of the segment
E. prescribing trifocals
48. Children with anisometropia should be
A. partially corrected
13. treated as if they were amblyopic
C. fully corrected
D. given bifocals
E. none of these
7

8. 49. Tilting glasses will cause
A. more prism
B. more cylinder to be induced
C. more sphere to be induced
D. both cylinder and sphere to be induced
E. less distortion
50. All the following are true of accommodation EXCEPT that it is
A. related to convergence
B. innervated via the III cranial nerve
C. central in origin
D. not susceptible to fatigue
E. a synkinesis
51. The operation of which instrument is based on one of the Purkinje-sanson images?
A. Indirect ophthalmoscope
B. Retinoscope
C. slit lamp
D. Keratometer
E. Cross cylinder
52. In progressive (malignant) myopia, one may have all the following EXCEPT
A. very thin sclera
B. that the choroid becomes thickened
C. degeneration of the photoreceptors and pigment epithelium
D. peripapillary atrophy
E. that breaks may occur in Bruch's membrane
53. Which of the following anatomic features has the strongest correlation with refraction?
A. Axial length of the eye
B. Anterior chamber depth
C. Corneal power
D. Lens power
E. Corneal curvature
54. An aphake will see an increase in image size of
A. 5%
B. 10%
C. 15%
D. 20%
E. 30%
55. Pincushion distortion is due to the
A. periphery of the lens magnifying more than the center of the lens
B. center of the lens magnifying more than the periphery of the lens
C. thickness of the lens
D. base curves of the lens
E. size of the pupil
56. All the following will tend to seek early help for presbyopic symptoms EXCEPT the
A. short person
B. watchmaker
C.hyperope
D. contact-lens corrected myope
8

9. E. myope
57. All the following are contraindications to the use of contact lenses EXCEPT
A. inflammatory conditions of the cornea
B. muscle imbalance
C. dusty environmental condition
D. poor motivation
E. keratoconjunctivitis sicca
58. Aniseikonia may be corrected using
A. prisms
B. an astronomical telescope
C. Galilean telescope
D. decentration of the lenses
E. aspheric lenses
59. An indirect ophthalmoscope will project a/an
A. virtual image
B. real image
C. upright image
D. flat image
E. condensed image
60. A lensometer measures the
A. vertex power of a lens
B. true power of a lens
C. equivalent power of a lens
D. front power of a lens
E. all of these
61. All the following are true of spherical lenses EXCEPT that they
A. have the same radius of curvature in all meridians
B. have the same power in all meridians
C. can be considered to be composed of variable prisms
D. can collapse the conoid of Sturm
E. can transfer the conoid of Sturm
62. All the following are true of cylindrical lenses EXCEPT that
A. their maximum power is at 90
o
to the axis
B. they have no power in its axis
C. they will have variable power
D. they have spherical surfaces
E: they can collapse the conoid of Sturm
63. All the following are true of prisms EXCEPT that
A. the angle of incident light will help determine the amount of deviation
B. the apical angle will help determine the amount of deviation
C. they may provide some refractive power
D. the index of refraction of a prism will play a role in the amount of deviation
E. they are responsible for "chromatic aberration" in glasses
64. Which of the following lenses has a spherical equivalent of -3.25?
A. -3.00 = +6.00 x 180°
B. -1.00 = -4.50 x 90°
9

10. C. -4.00 = -4.00 x 90°
D. -2.00 = -5.50 x 180°
E. -6.00 = +2.00 x 90°
65. All are true of a hyperopic eye EXCE PT that
A. it is deficient in refractive power
B. it is a "negative" eye
C. it has its far point behind the retina
D. accommodation will help correct some of the hyperopia
E. presbyopia will be delayed
66. All are true of axial hyperopia EXCEPT that
A. refracting elements of the eye may be normal
B. it will be associated with a short anterior-posterior length
C. it may be associated with glaucoma
D. it will have a large conoid of Sturm
E. the optic disc may look edematous ("pseudopapilledema")
67. All the following are true of aphakes when testing their visual fields EXCEPT that
A. spectacle-corrected aphakes can be tested only for their central 30
o
of field
B. contact lenses will eliminate all visual field anomalies of aphakia
C. the aphakic blind spot is closer to fixation.
D. the aphakic field may be tested on the perimeter without correction
68. Symptoms of hyperopia include all the following EXCEPT
A. distance vision impairment with high refractive errors
D. early blurring of near vision
C. accommodative insufficiency
D. frontal headaches
E.earlier presbyopia
69. All the following are related to a ring scotoma EXCEPT that it
A. is responsible for the "Jack-in-the-box" phenomenon
B. is mostly noticeable at distances between 3 and12 feet
C. can be eliminated by contact lenses
D. is eliminated by corrected curve lenses
E. is produced by aphakic lenses
70. Corrected curve lenses will
A. reduce radial astigmatism
B. reduce spectacle thickness
C. improve light transmission
D. reduce reflections
E. reduce spherical aberration
71. Base curves of lenses can with a
A. lensometer
B. neutralizing lens
C. retinoscope
D. Geneva lens measure
E. lens caliper
72. Which of the following is equivalent to the crossed cylinders +3.00 x 90
o
and -1.00 x 180°
A. +3.00 = -4.00 x 180°
10

11. B. +3.00 = -3.00 x 90°
C. +3.00 = -4.00 x 90°
D. -1.00 = -4.00 x 180°
E. -1.00= +3.00 x I80°
73. During fogging, the patient reports that the line from 1 o'clock to 7 o'clock is sharpest. At
what axis would you add minus cylinder?
A. 90°
B. 60°
C. 30°
D. 120°
E. 150°
74. An eye with an amplitude of accommodation of 5 diopters has a near point of 20 cm. Where
is the far point of this eye?
A. 33-1/3 cm in front of the eye
B. 20 cm in front of the eye
C. At infinity
D. 20 cm behind the eye
E. 50 cm behind the eye
75. A +12. 00 D lens at 15 mm in front of the eye is to be moved to 10 mm. Its power should be
A. 12.2 D
B. 12.4 D
C. 12.6 D
D. 12.8 D
E. 13.00 D
76. A -10.00 D lens at 15 mm is to be converted to a contact lens. Its power should be
A. -8.48 D
B. -8.53 D
C. -8.69 D
D. -9.45 D
E. -9.25 D
77. A 5-diopler myope can be corrected with a -8.00 D lens. Where should you place the lens?
A. 6 cm in front of the eye
B. 7 cm in front of the eye
C. 7.5 cm in front of the eye
D. 8.00 cm in front of the eye
E. 8.5 cm in front of the eye
78. the best way to check the optical centers of eyeglasses is to
A. use a clear plastic ruler to find the geometric center of the lens
B. use a keratometer
C. calculate them from the refraction
D. use a lensometer with India ink marker
E. use a flashlight
79. All the following are signs of keratoconus EXCEPT
A. distortion of the retinoscopic reflex
B. distortion of the direct ophthalmoscopic reflex
C. distortion of the reflex in the placido disc
11

12. D. poor indirect ophthalmoscopic view
E. distortion of the keratometer mires
80. Using a schematic eye, what will be the size of a 20/200 letter on the retina when viewed at
6 meters?
A. 0.1 mm
B. 1 cm
C. 0.24 mm
D. 0.5 mm
E. 0.7 mm
81. Retinoscopy at 67 cm gives you a +4.00 x 90° and +7.00 x 180°. What glasses do you try
for this patient?
A. +4.00 = +7.00 x 180°
B. +2.50 = +3.00 x 180°
C. +7.00 = +4.00 x 90°
D. +7.00 = +4.00 x 180°
E. +3.00 = +4.00 x 90°
82. An image is focused 50 cm to the right of a lens. The object is located 12.5 cm to the left of
the lens. What should be the power of the lens?
A. +3 D
B. + 5 D
C. + 7 D
D. + 8 D
E. +10 D
83. A 5-cm object is located 25 cm to the left of a +3.00 spherical lens. What is the linear
magnification?
A.2
B. 3
C. 6
D. 5
E. 4
84. A patient with an amplitude of accommodation of 1 diopter wears a +2.50 add and a +1.25
intermediate add. Through which distance will he see clearly?
A. 40 cm to 45 cm
B. 28.5 cm to 45 cm
C. 40 cm to 80 cm
D. 45 cm to 80 cm
E. 80 cm to 100 cm
85. Which of the following K readings are “with the rule”?
A. 43.0 / 44.0 at 90
o
B. 44.0 / 44.0 at 180
o

C. 44.0 / 46.0 at 180
o
D. 42.0 / 46.0 at 120
o

E. None of these
86. Which of the following are “against the rule” keratometry readings?
A. 44.0 / 44.0 at 90
o
B. 45.0 / 45.0 at 180
o
C. 44.0 / 46.0 at 180
o
12

13. D. 43.0 / 48.0 at 120
o
E. 42.0 / 43.0 at 150
o
87. All the following are specific indications for cycloplegic refraction EXCE PT
A. accommodative spasm
B. hyperopia
C. strabismus
D. youth
E. contact lens fitting
88. If one were to examine the general population for corneal astigmatism, one would most
likely find
A. against-the-rule astigmatism
B. with-the-rule astigmatism
C. irregular astigmatism
D. no astigmatism
E. oblique astigmatism
89. Irregular corneal astigmatism can be best corrected with the use of
A. spectacles
B. corrected curve spectacles
C. a galilean telescope
D. contact lens
E. aspheric glasses
90. Retinoscopy and keratometry confirm that all the astigmatism is corneal. How can this best
be corrected?
A. Only with the use of soft contact lenses
B. Only with the use of hard contact lenses
C. Only with the use of spectacles
D. With the use of hard contact lenses or spectacles
E.None of these
91. A patient is found to have a spherical cornea and on retinoscopy is found to have a
significant cylindrical error. All following statements are true EXCEPT that this patient
A. may have lenticular astigmatism
B. will see better with spectacles
C. will see better with contact lenses
D. will have equal K readings in both meridians
92. Which is true of refractive myopia?
A. Increased incidence of retinal detachment
B. Macular changes
C. myopic crescent
D Lens changes
E. All of these
93. With regard to the cornea, all the following pairs are correctly matched EXCEPT
A. more convex/steeper
B. less convex/flatter
C. steeper/ more power
D. more power/hyperopic
94. Myopia can be associated with all the following EXCEPT
13

14. A. decreased convexity of the lens
B. increased corneal curvature
C. increased axial length of the eye
D. a lens closer to the cornea
E. excessive plus power
95. The usual age at which myopia first becomes apparent is
A. 8 years
B. 15 years
C. 20 years
D. 25 years
96. All the following can cause a decrease in the amplitude of accommodation EXCE PT
A. siderosis
B. phospholine iodide
C. cycloplegic drops
D. ocular trauma
E. aging
97. A patient has amplitude of accommodation of 4.00 D. At what distance wii he be able to
read comfortably?
A. 25 cm
B. 33 -1 /3 cm
C. 50 cm
D. 60 cm
E. 80 cm
98. A myope will experience
A. magnification with glasses
B. less minification with contact lenses than with glasses
C. magnification with contact lenses
D. less minification with glasses than with contact lenses
E. none of these
99. The axially ametropic eye is best corrected with
A. glasses located at the near point
B. hard contact lenses
C. glasses located at the anterior focal point of the eye
D. soft contact lenses
100. All the following will tend to increase "with-the-rule" astigmatism following cataract surgery
EXCEPT
A. deeply placed corneoscleral sutures
B. 7-0 chromic sutures
C. corneoscleral incision in the mid limbus
D. continuous suturing with nylon
14