Multiple Choice Questions
OPTICS AND REFRACTION
1. Crystalline lens absorbs light rays shorter than:
A. 295 nm
B. 350 nm
C. 390 nm
D. 490 nm
2. The prism produces displacement of the objects seen through it towards the:
A. Apex
B. Base
C. Sideways
D. None of the above
3. The critical angle refers to the angle of incidence in the denser medium, corresponding to which angle of refraction in the rarer medium is:
A. Less than 90°
B. 90°
C. More than 90°
D. Equal to angle of incidence
4. The refractive power of an emmetropic eye is about:
A. +50D
B. +55D
C. +60D
D. +65D
5. In the media of the eye, highest refractive index is of the:
A. Cornea
B. Aqueous humour
C. Lens
D. Vitreous humour
6. The anterior focal length of the schematic eye is:
A. 15.7 mm
B. 17.2 mm
C. 13 mm
D. None of the above
7. The posterior focal point of the reduced eye situated on the retina is how many millimetre behind the anterior surface of cornea:
A. 22.9 mm
B. 24.4 mm
C. 23 mm
D. 21 mm
8. The optical axis of the eye meets the retina at a point which:
A. Coincides with the fovea centralis
B. Is nasal to the fovea centralis
C. Is temporal to the fovea centralis
D. Is nasal to optic disc
9. Visual axis of the eye meets the retina at a point which:
A. Coincides with the fovea centralis
B. Is nasal to fovea centralis
C. Is nasal to optic disc
D. Is temporal to fovea centralis
10. At birth eye is usually:
A. Hypermetropic
B. Myopic
C. Emmetropic
D. Aniseikonic
11. The most common type of refractive error is:
A. Hypermetropia
B. Myopia
C. Astigmatism
D. None of the above
12. One millimeter decrease in axial length of the eyeball leads to hypermetropia of:
A. 6 dioptres
B. 2 dioptres
C. 3 dioptres
D. 4 dioptres
13. One millimeter increase in the radius of curvature of cornea leads to hypermetropia of:
A. 3 dioptres
B. 4 dioptres
C. 5 dioptres
D. 6 dioptres
14. In an aphakic eye the anterior focal point from the anterior surface of cornea is about:
A. 15 mm
B. 21 mm
C. 23 mm
D. 31 mm
15. In an aphakic eye posterior focal point from the back of cornea is about:
A. 23 mm
B. 25 mm
C. 31 mm
D. 21 mm
16. The standard power of an intraocular lens implanted in the posterior chamber is:
A. 18 dioptres
B. 20 dioptres
C. 23 dioptres
D. 25 dioptres
17. An aphake wearing aphakic glasses will most commonly notice:
A. Pincushion distortion
B. Spherical aberration
C. Barrel distortion
D. Chromatic aberration
18. Sturm’s conoid refers to configuration of the rays refracted through:
A. Concave spherical surface
B. Convex spherical surface
C. Toric surface
D. Irregular surface
19. Because of circle of least diffusion, the distant vision is comparatively good in:
A. Simple myopic astigmatism
B. Compound myopic astigmatism
C. Mixed astigmatism
D. Compound hypermetropic astigmatism
20. A difference in the size of two retinal images which can be well tolerated is:
A. 2 percent
B. 3 percent
C. 5 percent
D. 10 percent
21. In Against-the-rule astigmatism:
A. Vertical meridian is more curved than the horizontal
B. Horizontal meridian is more curved than the vertical
C. Both meridia are equally curved
D. None of the above
22. Radial keratotomy corrects myopia by causing:
A. Steepening of cornea
B. Flattening of cornea
C. Shortening of cornea
D. Pin-hole effect
23. Range of accommodation is the distance between:
A. Far point and near point of the eye
B. The eyes and the near point
C. The eyes and the far point
D. The retina and the near point
24. Causes of premature presbyopia include all of the
following except:
A. General debility
B. Primary open-angle glaucoma
C. Uncorrected myopia
D. Premature sclerosis of the lens
25. During accommodation, there occurs decrease in the radius of curvature of the:
A. Anterior surface of the lens
B. Posterior surface of the lens
C. Both surfaces of the lens
D. None of the above
26. Near point of the eye varies with:
A. The age of the patient
B. The static refraction of the eye
C. Both of the above
D. None of the above
27. Far point of the eye varies with:
A. The age of the patient
B. The static refraction of the eye
C. Both of the above
D. None of the above
28. Bilateral paralysis of accommodation can occur in patients with:
A. Diabetes
B. Syphilis
C. Diphtheria
D. All of the above
E. None of the above
29. During retinoscopy with a plane mirror from a distance of 1 M, no movement of pupillary red reflex with the movement of the mirror indicates:
A. Emmetropia
B. Myopia of 1 D
C. Hypermetropia of less than 1 D
D. All of the above
30. The end point of streak retinoscopy is:
A. Neurtalization of the red reflex
B. Streak disappears and the pupil appears completely light or dark
C. Just reversal of the red reflex
D. All of the above
31. The fastest acting cycloplegic drug is:
A. Atropine
B. Tropicamide
C. Cyclopentolate
D. Homatropine
32. All of the following are true about auto-refractometry except:
A. Quick procedure
B. Gives information about spherical and cylindrical error
C. Measures interpupillary distance
D. Subjective verification of refraction is not required
33. While performing duochrome test, if the patient reports that he sees red letters more clear than green, it indicates that he is slightly:
A. Myopic
B. Hypermetropic
C. Presbyopic
D. None of the above
34. While performing subjective verification of refraction, the cross cylinder is used to check:
A. Axis of the cylinder to be prescribed
B. Power of the cylinder to be prescribed
C. Both of the above
D. None of the above
35. The principle of the stenopaeic slit test is based on:
A. Astigmatic fan
B. The circle of least diffusion
C. Pin-hole phenomenon
D. Sturm’s conoid
36. Preferably presbyopia should be:
A. Fully corrected
B. Under corrected
C. Over corrected
D. None of the above
37. Soft contact lenses are made of:
A. Polymethyl methacrylate
B. Hydroxymethyl methacrylate
C. Glass
D. Silicone
E. All of the above
38. Consistency of the gas permeable contact lenses is:
A. Hard
B. Soft
C. Semisoft
D. None of the above
39. Contact lens is best used in:
A. High myopia
B. Irregular astigmatism
C. Aphakia
D. Regular astigmatism
40. Excessive accommodation causes:
A. Hypermetropia
B. Myopia
C. Pseudomyopia
D. Pseudohypermetropia
41. Haemorrhage at macular spot in high myopia is called:
A. Lacquer’s lines
B. Foster-Fuchs fleck
C. Dalen-Fuchs nodules
D. Berlin’s oedema
42. Over correction is preferable in:
A. Myopia
B. Presbyopia
C. Hypermetropia
D. Aphakia
43. Kappa angle is the angle between the:
A. Pupillary axis and visual axis
B. Visual axis and optical axis
C. Centre of eyeball rotation and line of fixation
D. None of the above is correct
44. Alpha angle is the angle between the:
A. Pupillary axis and optical axis
B. Visual axis and optical axis
C. Centre of eyeball rotation and line of fixation
D. None of the above is correct
45. Unit of light emitted from a surface is:
A. Lambert
B. Candella
C. Lux
D. Lumen
46. Astigmatism is considered to be:
A. Spherical abberation
B. Curvatural ametropia
C. Axial ametropia
D. Index ametropia
47. Presbyopia is due to:
A. Loss of elasticity of lens capsule
B. Weakness of ciliary muscle
C. Weakness of suspensory ligament
D. All of the above
48. The term anisometropia indicates:
A. Refractive error
B. Long vision
C. Short vision
D. Ageing process
49. Facultative hypermetropes manage to see because of:
A. Wrinkling of eye
B. Ciliary muscle contraction
C. Accommodation
D. Use of cycloplegics
50. Constantly changing refractive error is seen in:
A. Traumatic cataract
B. Diabetic cataract
C. Morgagnian cataract
D. Intumescent cataract
51. Maximum refractive power is due to the:
A. Anterior surface of lens
B. Posterior surface of lens
C. Anterior surface of cornea
D. Posterior surface of cornea
52. The most accepted method for treatment of a myopic with refractive error of 2D is:
A. Spectacles
B. Contact lens
C. Radial keratotomy
D. Excimer laser
53. Which is the most common complication of high myopia:
A. Glaucoma
B. Cataract
C. Haemorrhage
D. Retinal detachment
54. Lattice degeneration is seen in:
A. Myopia
B. Hypermetropia
C. Aphakia
D. Presbyopia
55. The power of reduced eye is:
A. 17 D
B. 45 D
C. 59 D
D. 66 D
56. Aniseikonia refers to:
A. Difference in the corneal diameter
B. Difference in the image size (retinal image)
C. Difference in the refractive power
D. Difference in image colour
57. A female patient wants LASIK surgery for her eye. She asks for your opinion. All the following thing sare suitable for performing LASIK surgery except:
A. Myopia of 4 diopters
B. Age of 15 years
C. Stable refraction for 1 year
D. Corneal thickness of 600 microns
58. Accommodation is maximum at the age of:
A. 25 years
B. 5 years
C. 14 years
D. 30 years
59. Image formed by a prism is:
A. Virtual, erect and displaced towards its apex
B. Real, erect and displaced towards its base
C. Real, inverted and displaced towards its apex
D. Virtual, inverted and displaced towards its base
60. Presently surgical treatment of choise in a 22 year male with - 10D myopia is:
A. Phakic refractive lens
B. Refractive lens exchange
C. Wavefront guided LASIK
D. LASIK with femtosecond laser
61. Visual axis is:
A. Center of cornea to retina
B. Object to fovea
C. Center of lens to cornea
D. None
62. Foster’s fusch’s spots are seen in:
A. Hypermetropiea
B. Myopia
C. Astigmatism
D. None
63. Jack in box scotoma is seen after correction of Aphakia by:
A. IOL
B. Spectacles
C. Contact Lens
D. None
64. Accommodation is due to:
A. Relaxation of ciliary muscles
B. Contraction of ciliary muscles
C. Contraction of dilator pupillae
D. None
65. Objective assessment of the refractive state of the eye is termed:
A. Retinoscopy
B. Gonioscopy
C. Ophthalmoscopy
D. Keratoscopy
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