Sample Test Items. 2. Which of the following photometric concepts describes luminous energy per unit area falling onto a surface?

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1 Sample Test Items PART A Optics and Optical Appliances 1. Light excitation of rhodopsin causes: a) isomerisation of all-trans-retinal to 11-cis-retinal b) isomerisation of 11-cis-retinal to all-trans-retinal c) retinol oxidation to retinal d) hydrolysis of retinyl-fatty acid ester to retinol plus fatty acid 2. Which of the following photometric concepts describes luminous energy per unit area falling onto a surface? a) Luminous intensity b) Illuminance c) Luminance d) Radiance 3. Consider the following patient information: Distance Rx: R & L DS Eye size: 52 mm (round) Bridge size: 20 mm PD: 64- mm Using a finished blank, but making no allowance for cutting and edging errors, what is the minimum blank size that can be used to fabricate these lenses? a) 52 mm b) 56 mm c) 60 mm d) 64 mm 4. A contact lens with a refractive index of 1.49 is made with a spherical front surface and a toric back surface. The back surface of the contact lens perfectly matches the toric surface of the cornea that has a refractive index of The surface power of the horizontal meridian of the cornea is D and the surface power in the vertical meridian is D. The amount of corneal astigmatism remaining with the contact lens in place is: a) 0.00 D b) 0.58 D c) 1.03 D d) 1.15 D e) 1.67 D 1

2 5. A patient tilts a lens with a power of DS, and a refractive index of 1.50, so that he looks obliquely through the optical centre at an angle of 20 degrees. The resultant power will be: a) DS/-1.38 DC x 180 b) DS/-3.68 DC x 180 c) DS/-1.38 DC x 180 d) DS/-3.68 DC x An artist who uses indistinct borders and a bluish tint to represent distant objects, is employing which of the following secondary distance cues? a) Overlap (superimposition) b) Aerial perspective c) Light, shade, and shadow d) Parallax 7. A person with a neutral density filter over his left eye, views a target undergoing simple harmonic motion in the fronto-parallel plane. The target trajectory will appear: a) elliptical and clockwise b) elliptical and anticlockwise c) planar and rotated toward the right side d) planar and rotated toward the left side 8. A patient has the following prescription: R: DS/-0.75 DC x 180 L: DS/-0.75 DC x 180 The patient views a near object through these lenses in a trial frame. You observe that her lines of sight are about 10 mm below the geometric centres of the test lenses. You measure a vertical imbalance of 1 prism dioptre right hyperphoria in this position. If you remove the lenses and repeat the measurement you should expect to find: a) 1.5 prism dioptres of left hyperphoria b) 3.5 prism dioptres of left hyperphoria c) 1.5 prism dioptres of right hyperphoria d) 3.5 prism dioptres of right hyperphoria 9. The isopter for a 1 mm white test object used in a 1 m tangent screen examination has a radius of approximately: a) 5 degrees in all meridians b) 15 degrees in all meridians c) 25 degrees in all meridians d) 15 degrees temporally and 25 degrees nasally e) 15 degrees nasally and 25 degrees temporally 2

3 PART B Clinical Investigation and Management 10. A patient presents for contact lens fitting with the following profile: Refraction Right -3.00/-1.50 x 180 Left -2.00/-1.75 x 175 Keratometry 7.80 along along along along 90 Which of the following would be the most suitable contact lens for this patient? a) Spherical soft lens b) Toric soft lens c) Spherical hard lens d) Bi-toric hard lens 11. A 21 year old female complains of difficulty driving at night because her vision is 'blurred'. Her refraction is: Vision 6/9+ Right plano/-0.75 x 170 VA 6/6+ Vision 6/9 Left plano/-0.50 x 10 VA 6/6+ Her mother is diabetic and her father developed cataract at the age of 64. The most likely cause of her symptoms is: a) early nuclear sclerosis cataract b) undiagnosed diabetes c) night myopia d) decompensated heterophoria 12. Following the removal of a right traumatic cataract and implant, a 21 year old office worker has the following spectacle prescription: Vision 6/9+ Right plano/-0.75 x 170 VA 6/6+ Vision 6/9 Left plano/-0.50 x 10 VA 6/6+ Which of the following will be the best management for this patient? a) The use of spectacles for near vision b) A combined varifocal/single vision spectacle c) A contact lens for the right eye d) A pair of multifocal lenses 13. During slit lamp evaluation of a soft contact lens patient, you identify a pattern of wavy line staining with fluorescein. The staining is in the deeper layers of the epithelium and appears to end in rounded 'bulbs'. The most likely cause of this condition is: a) A herpes zoster infection of the cornea b) A herpes simplex infection of the cornea c) An acanthamoebal infection of the cornea d) A foreign body abrasion of the cornea 3

4 14. If a person with no oculomotor abnormality tilts his head 30 degrees toward 1 shoulder, his eyes will counter-roll approximately: a) 0 degrees b) 6 degrees c) 20 degrees d) 40 degrees 15. A mother brings her 4 year old son to you because she has noticed that his left eye sometimes turns in. Retinoscopy (skiascopy) reveals the following refractive error: R +3.50/-0.75x90 VA 6/6 measured with single letters L +2.75/-0.50x85 VA 6/6 measured with single letters With this correction he exhibits 10pdpt esophoria at distance and 15pdpt esophoria at near. The next step should be to: a) refer the child for surgery b) prescribe the retinoscopy findings c) prescribe a bifocal correction d) perform a cycloplegic examination 16. A 45 year old male patient comes to see you for his first pair of reading spectacles. His refraction is right and left Plano VA 6/6. He needs a reading addition to give N5. Ophthalmoscopy reveals pale discs with a cd ratio of 0.6. There is some undercutting of the superior and inferior disc margins in each eye. Applanation tonometry at 17.00hrs reveals intra ocular pressures of R 23mm Hg and L 25mm Hg. The most appropriate course of action to undertake next would be to: a) screen the peripheral (60º) visual field b) perform threshold central visual field examination c) repeat the tonometry readings first thing in the morning d) undertake gonioscopic examination of the anterior chamber 17. A 75 year old man consults you for an eye examination. He is aphakic (without implants) and has age related macular changes reducing his visual acuity. Your findings are as follows: Right /-1.50 x 80 VA 6/18 Left /-1.75 x 105 VA 6/18 BVD= 12mm With a addition he manages to read N12 binocularly and with a addition he manages N5. Which of the following will provide the most satisfactory way of correcting his near vision? a) Distance contact lenses and reading glasses b) Distance glasses plus hand held x3 magnifier c) Binocular spectacle mounted telescopic magnifier d) Full reading prescription in reading form 4

5 18. A 2½ year old child is found to have the following prescription: Right Left If the refractive error is not corrected, which of the following will be the most likely outcome? a) Normal development b) Development of convergent strabismus c) Development of divergent strabismus d) Anisometropic amblyopia PART C Biological and Medical Sciences 19. The T- wave of the electro-cardiogram represents: a) depolarisation of the atria b) depolarisation of the ventricles c) repolarisation of the atria d) repolarisation of the ventricles 20. The presence of a relative afferent pupil defect indicates reduced neurological transmission from: a) the affected eye to the brain b) the brain to the affected eye c) the brain to the unaffected eye d) both eyes to the brain 21. Which mode of secretion is demonstrated by the tarsal (meibomian) glands? a) Holocrine b) Merocrine c) Apocrine 22. Which group of biomolecules have the general formula (CH 2 O)n? a) Amino acids b) Fatty acids c) Nucleotides d) Monosaccharides 23. Examination of the peripheral retina is most easily achieved using: a) a gonioscopy lens b) slit lamp binocular indirect ophthalmoscopy c) a Hruby lens d) headband binocular indirect ophthalmoscopy 5

6 24. A 29 year old female visits an optometrist complaining of headaches for a two week period. Her visual acuities are 6/6 in both eyes. The ocular examination is normal. Visual fields analysis shows a bitemporal hemianopia. The most likely diagnosis is: a) optic nerve lesion b) visual cortex lesion c) chiasmal lesion d) optic radiation lesion 25. Which of the following types of cells would be prevalent in a smear from a nonspecific viral conjunctivitis? a) Monocytes b) Polymorphonuclear leucocytes c) Eosinophils d) Epithelial cells 26. Which of the following transmitter substances is released at the presynaptic neuromuscular junctions in the extraocular muscles? a) Noradrenaline b) Adrenaline c) Dopamine d) Acetycholine 27. Which of the following local anaesthetics is an example of an amide type? a) Oxybuprocaine (benoxinate) b) Proxymetacaine (proparacaine c) Lignocaine d) Amethocaine Correct Responses to Sample Test Items Part A 1.b 2.b 3.b 4.c 5.a 6.b 7.a 8.a 9.c Part B 10.b 11.c 12.b 13.b 14.b 15.d 16.b 17.d 18.d Part C 19.d 20.a 21.a 22.d 23.d 24.c 25.a 26.d 27c 6