Optometry and Ophthalmology MCQ, Part-09

01. If undilated retinoscopy is done at a distance of 1/2m, Distance correction needed is

A. 0.5 D
B. 1.0 D
C. 1.5 D
D. 2.0 D✓

Distance Correction needed =1/w.d
  • If working distance is 2/3m correction needed will be 3/2=1.5D
  • If it is 1/2m =correction 2D.

02. In cycloplegic retinoscopy using 1%atropine, the amount of diopters deducted to compensate ciliary muscle tone is

A. 0 D
B. 0.5 D
C. 1 D✓
D. 1.5 D

03. In a patient with dilated pupils, if central and peripheral shadow movements are different, it is important to neutralize

A. Central shadow✓
B. Peripheral shadow
C. Both the shadows
D. None

04. ________ is also known as dry retinoscopy

A. Cycloplegic retinoscopy
B. Non cycloplegic retinoscopy✓
C. Dynamic retinoscopy
D. Autorefractometry

05. In retinoscopy, Use of cycloplegic drugs are contraindicated in patients with ______

A. Primary open angle glaucoma
B. Primary angle closure glaucoma✓
C. Cataract
D. Spasm of Accommodation

06. The refractive condition where 1 point of focus falls on the retina and the other point of focus falls in front of the retina

A. Simple myopic astigmatism✓
B. Compound myopic astigmatism
C. Simple hypermetropic astigmatism
D. Compound hypermetropic astigmatism

07. A refractive condition in which rays of light come to 2 focal points is correctable with

A. Spherical lens
B. Cylindrical lens✓
C. Prism
D. None

08. Which of the following is the best term that implies perfect vision?

A. Ametropia
B. Emmetropia✓
C. Isometropia
D. Orthophoria

09. Retinoscopy is

A. Visualization of retina alone
B. Visualization of retina and all other posterior segment contents
C. Objective measurement of the refractive error of patient✓
D. Subjective measurement of the refractive error of patient

10. What is the most common refractive error of the human eye?

A. Myopia
B. Hypermetropia
C. Astigmatism✓
D. Presbyopia

11. Javal's rule is used to estimate which type of Refractive error?

a. Myopia
b. Hypermetropia
c. Astigmatism✓
d. Presbyopia

12. Temporal crescent is seen typically in

a. astigmatism
b. hypermetropia
c. myopia✓
d. none of the above

13. Optical condition of the eye in which the refraction of the two eyes differs is

a. Isometroia
b. Anisocoria
c. anisometropia✓
d. compound astigmatism

14. Out of the following which is the shortest acting mydriatic

a. tropicamide✓
b. homatropine
c. cyclopentolate
d. atropine

15. People with which type refractive error are at high risk for PACG

a. Myopia
b. Hypermetropia✓
c. Astigmatism
d. Presbyopia

16. Placido’s Disc may be used in all except

A. Regular Astigmatism
B. Keratoconus
C. Keratometry✓
D. Corneal aberrations

In regular corneal astigmatism the circle will be seen as oval. In keratoconus the concentric circles are seen distorted. Placido's disc is also used to differentiate corneal opacity from aberrations.

Ordinary Placido's disc is not used for keratometry, but modern Placido's disc based instruments uses scheimpflug technology for corneal topography. The Galilei Dual Scheimpflug Analyzer used for corneal topography is a noncontact instrument composed of a placido-disc topographer and a dual rotating Scheimpflug camera.

17. The total refractive power of the aphakic eye is

A. 38D
B. 43D✓
C. 60D
D. 20D

In an aphakic eye the only refractive surface is cornea.

18. Retinal image size in uncorrected hypermeropic eye is

A. Big
B. Small✓
C. Normal
D. None

Since hyperopic eye is small, retina is close to nodal point. So image size will be small.

19. Power of lens with 10cm focal length

A. 1/10D
B. 1D
C. 10D✓
C. 100D
D=1/f, but remember f should be in meter.

20. Water silk appearance in retina is seen in

A. Pathological myopia
B. Simple myopia
C. Hypermetropia✓
D. High astigmatism

21.Lens with a long focal length is

A. Thick
B. Thin
C. Not strongly curved
D. Both B and C✓

22. Test not used in astigmatism

A. Stenopaeic slit
B. Maddox V
C. Jackson's cross cylinder
D. Bagolini striated glasses✓

23. Total internal reflection occur when a ray of light passes from

A. Denser medium to rarer medium✓
B. Rarer medium to denser medium
C. One medium to another of same refractive index
D. None

24. Stiles-Crawford effect is more sensitivity of the retina to

A. Perpendicular rays than the oblique rays✓
B. Bright ight than dim light
C. Bright colours than dull colours
D. Quick movement than slow movement

Stiles-Crawford effect is a natural mechanism to reduce optical abberations in human eye. Other mechanisms include Cutting off of the peripheral rays by iris, High refractive index of the nucleus of the lens than that of the cortex, Low sensitivity of the peripheral retina, Oval shape of the eye ball. etc.

25. Anisometropia up to how much Diopters is well tolerated

A. 0.5 D
B. 1.0 D
C. 2.5 D✓
D. 5.0 D

0.5 D difference between the power causes 1% difference in retinal image size. Upto 5% difference is easily tolerated by brain. More than that may cause diplopia.

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