QUESTION BANK FINAL

501 121. Occipital lobe lesions lead to ………. A]. Central field loss b]Homonymous Hemianopia c].Total Blindness Ans : B]Homonymous Hemianopia 122. The total length of the optic nerve is ………… a] 40mm b] 3 cm c] 4.5 cm d] 5 cm Ans : A] 40mm 123. If there is a lesion in the entire optic nerve the condition will lead to ………. A.]Peripheral defect b].superior defect c].complete blindness Ans : c].complete blindness 124. The lesions at the optic chiasm and after optic chiasm will cause ……… A.]Monocular defect b].binocular defect c].total blindness Ans : b] binocular defect 125. Hemi means …………… A.]Quarter b.]Half c].full Ans : b.]Half 126. Normal field of vision extends on the nasal side to………… a] 40° b]50° -600 c] 60° Ans : b]50° -600 127. Visual centre is situated in ……. REFRACTION DEPARTMENT-CBE

502 b]frontal lobe c]occipital lobe Ans : c]occipital lobe a] parietal lobe c] latral geniculate body 128. Optic nerve extends up to ………… Ans : a] optic chiasma a] optic chiasma b]optic tracts c] 400 – 700 µm Ans : c] 400 – 700 µm 129. Visible spectrum extends from ------ a] 100 – 300 µm b] 300 – 650 µm III. FILL IN THE BLANKS : 1. The amsler grid test, determines the presence and location of defects in the …… portion of the visual field Ans : central 2. A defective visual field surrounded by a normal field is known as ……… Ans : scotoma 3. .………… is the procedure of estimating the extent of visual fields Ans :Perimetry 4. The normal monocular field in superior side ----------- Ans : 60degree-70degree 5. Normal binocular visual field in horizontal side -----------

503 Ans : 200degree 6. Physiological blind spot is also called as ------------ Ans : Absolute scotoma 7. Blind spot is located 15degree ---------- to the fixation point Ans : temporal 8. The normal measurement of ---------- in 5.5mm horizontally and 7.5mm vertically Ans : blind spot 9. Blind spot corresponds to the region of the ----------- Ans : optic nerve head 10. Traquair’s definition of the visual field it is an -------- in the sea of blindness Ans : Island of vision 11. In visual field the end organ is the ----------- of the rods and cones Ans : neural epithelium 12. The second order neurone is the ------ of the retina Ans : ganglion cell 13.--------- will have same field defect size regardless of the target size and brightness Ans : Absolute scotoma 14. In ------ the patient has complaints of non-seeing area Ans : positive scotoma REFRACTION DEPARTMENT-CBE

504 15. Optic disc corresponds to ----------- of visual field. Ans : blind spot 16. What is the other name of double arcute Ans : Ring scotoma /Annular scotoma 17. ........is the procedure to estimate the extent of visual field. Ans :Perimetry 18. ........the main aim is to find out the threshold of the retina at various points Ans : Static Perimetry 19. ....... is that portion of space in which objects are simultaneously visible to the steady fixing eye Ans : The visual field 20. The ……… visual fields is slightly irregular oval Ans : Normal monocular 22. The ……….. is the portion of the visual field within 30º radius of fixation Ans : central field 23. The ………. makes up the remainder of the visual field Ans : peripheral field 24. Normal monocular fields in nasal side …….. temporal side…….. Ans : 50º to 60º, 100º to110º

505 25.Normal monocular fields in superior side …….., inferior side…… Ans : 60º to 70º, 70º to 80º 26. Normal binocular fields in horizontal side……. vertical side……… Ans : 200º , 110º 27. ……… is an area of absolute scotoma Ans : Physiological blind spot 28. Blind spot is located approximately …….temporal to the fixation point and about…………below the horizontal meridian Ans : 15º , 15º 29. The normal measurements of the blind spot is approximately………. horizontally and ……….. vertically Ans : 5.5mm , 7.5mm 30. Expansion of AION: …………… Ans : Anterior Ischemic Optic Neuropathy 31. In traquair's concept the peak of the island represents the point of…………. Ans : highest acuity 32. The nomenclature of perimetryare termed …………… Ans :Isopters 33.The nasal field represents the …… and temporal field represents the ……………… REFRACTION DEPARTMENT-CBE

506 Ans : temporal retina , nasal retina 34. The end organ is the neural epithelium of the …………… Ans : rods and cones 35.The first – order neurone is the bipolar cell with its axons in the ………….. Ans : inner layers of retina 30. The ………………. is the ganglion cell of the retina Ans : second order neurone 37. ………… is the visual center Ans : occipital cortex 38. The fibres from the peripheral retina enter the periphery of the……….. Ans : optic nerve 39. Loss of vision in one half of the visual field a condition known as………. Ans : hemianopia 40. Abnormal visual fields …………….. Ans : contraction, depression scotoma 41. Visual field depression may be devided into………….. Ans : general depression, local depression 42. A …… is an area of partial or complete blindness within the confines of a normal or a relatively normal visual field Ans : scotoma

507 43. Types of scotoma ………… Ans : absolute scotoma, relative scotoma 44. Relative scotoma two types……….. Ans : positive scotoma, negative scotoma 45. Positive scotoma example…………. Ans : central scotoma 46. Negative scotoma example …………….. Ans : blind spot enlargement 47. In ………… scotoma patient complaints of non seeing area Ans : positive 48. In ……….. Scotoma examiner detects the non seeing area Ans : negative 49. Scotoma may be……………. Ans :unilateral or bilateral 50. ………. scotoma will have the same field defect size regardless of the target size and brightness Ans : Absolute 51. ………… through fixation which divides superior and inferior visual fields Ans : Horizontal meridian 52. …………..through fixation which divides left and right visual field REFRACTION DEPARTMENT-CBE

508 Ans :Veritical meridian 53. line connecting points of equal visual sensitivity is…………. Ans :Isopter 54. Area of reduced visual sensitivity is ………… Ans : scotoma 55. Bjerrum scotoma other name……….. Ans : arcuate scotoma 56. ………… is defect involving fixation Ans : Central Scotoma 57. ……… defect encompassing the physiologic blind spot and fixation Ans :Ceco– central scotoma 58. ………… scotoma is defect close to but not involving fixation Ans : para – central 59. …………is complete loss of either superior or inferiorfield nasal to the physiologic blind spot Ans : Altitudinal 60. ………….. is defect respecting the vertical meridian Ans : Hemianopia 61. ……… Defect is respecting the vertical meridian involving only one Quadrant.

509 Ans :Quadrantanopia 62. …… defect occupies the same side of visual space in both eyes Ans : Homonymous 63. …… in bilateral hemianopic defects which are essentially indentical Ans : congruous 64. ArtericAION rarely seen…………. Ans : before 40 yrs 65. ……… ishemianopic defects which are not identical Ans : Incongruous 66. Double arcuate scotoma other name ……… Ans : Ring or annular scotoma 67. Ultimately all the nerve fibers are eventually destroyed with ……….. Ans : no perception of light 68. Double arcuate scotoma leads to……… Ans : Tubular field of vision 69. Only paracentral temporal island of vision persists ……… being destroyed Ans : central vision 70. ………… is the stimulus of known size and luminance is moved from periphery towards the center to establish isopters REFRACTION DEPARTMENT-CBE

510 Ans : kinetic perimetry 71. Various methods of kinetic perimetry are ………… Ans : confrontation, tangent screen scotometry, lister'sperimetry and goldman'sperimetry 72. Static perimetry is superior to the kinetic method for …… as it is more accurate and reproducible Ans : Glaucoma patients 73. Static perimetry example …………… Ans :Humphery Visual Fields Analyzer 74. ………… is done either in photopic or scotopic conditions Ans : Static perimetry 75. Bjerrum screen other name …………. Ans : Tangent screen 76. Estimation of defects of central fields using tangent screen is termed as …………… Ans :campimetry or scotometry 77. Toxic optic neuropathy caused by ........... Ans : alcohol, tobacco, drugs, nutritional deficiency 78. Fixation targets should be capable of variation from…………….. Ans : 1 to 10mm

511 79. ……… test determines the presence and location of defects in the central portion of the visual field Ans :Amsler grid 80. Perimeter screen may be either an arc or a bowl of a radius of ………… Ans : 330mm 81. Colour vision deficiency and bilateral centrocecal scotoma seen in……… Ans : Toxic optic neuropathy 82. LED expansion………….. Ans : Light Emitting Diodes 83.Automated perimeters can perform screening and diagnostic field test and can use …………….. Ans : Kinetic and Static methods 84. ……… has become the standard for visual field testing Ans :Humphery Field Analyzer 85. The targets of the perimeter consists of circular white discs of diameters ranging from …… Ans : 1 -10mm 86. The ……………is standardized and preferable for glaucoma examination Ans :Goldmann perimeter 87. The…….. is a recently developed visual field screening device Ans :Dematocampimeter REFRACTION DEPARTMENT-CBE

512 88. Amsler grid test the patient should perform the test monocularly always at the same ……………distance Ans : 16 inch 89. Field defects in chiasma ……. Ans :Bitemporal Hemianopia 90. Visual field defects in optictract……….. Ans : Contra Lateral Incongruous Homonymous Hemianopia 91. Visual field defect in optic radiation……………. Ans :Congrous Contralateral Homonymous Hemianopia 92. Normal binocular visual fields …………… Ans :Horizantal 200° and Vertical 130° or 110o 93. ………… Distance used for fields test. Ans : 1 meter (or) 2 meter 94. Portion of central field with in ………….radius of fixation. Ans : 30° 95. Portion of peripheral field with in …………radius of fixation. Ans : 330° 96. Other name of blind spot is………… Ans : physiological blind spot, absolute scotoma

513 97. Normal blind spot corresponds to the region of the………… Ans : optic nerve head 98. Visual fields invented by …….. Ans :Traquir 99. The second order neuron ……… Ans : Ganglion cell with axons in lateral geniculate body 100. The end organ is neural epithelium of the ……….. Ans : rods and cones 101. The first order neuron ………. Ans : Bipolar cells with axons in inner layer of retina 102. The third order neuron…………. Ans : Lateral geniculate body to occipital cortex 103. How many parts in visual pathway? ………. Ans : six 104. Loss of vision in the opposite half of the visual field a condition known as…….. Ans : Hemianopia 105. Swelling of the optic disc due to…………. Ans :papilloedma 106. Visual field depression may be divided in to………. REFRACTION DEPARTMENT-CBE

514 Ans : general depression, local depression 107. Types of scotoma are…………….. Ans : absolute scotoma, relative scotoma 108. Pale disc edema altitudinal scotoma seen in ………… Ans : AION 109. ……….. that changes with the target size and sloping borders indicates active (or) ongoing field defect. Ans : Relative Scotoma 113. Defect in same side of visual space in both eyes is called ………. Ans : Homonymous 114. Traquir’s definition of visual field is ………… Ans : Island of vision 116. In visual field testing if the fixation point is not seen it is called ……….. Ans : central scotoma 117. The field defect close to but not involving fixation is called ………. Ans : Para central scotoma 118. If the optic nerve is defected field defect is ………. Ans : blindness 119. If optic radiation in posterior occipital lobe is defect the field defect ………….

515 Ans :Iscontra Lateral Congruous Homonymous Haemianopia With Macular Sparing 120. Glaucoma field defect are ……… Ans : 9 types 121. Other name of Doublearcute scotoma………… Ans : Ring Scotoma 122. Nasal step scotoma is invented by………. Ans :Roenne 123. Early stage of glaucoma field defect is………… Ans : Blind Spot Enlargement 124. Last stage glaucoma field defect is …………. Ans : Tubular Field 125. Severe pain, rapd, colour vision defect is seen in……… Ans : Optic Neuritis 126. defect in pituitary adenoma………… Ans :Bitemporal Hemianopia 127. Visual f ields tested by………. Ans : Central Field, Peripheral Field, Confrontation Method, Amsler Grid 128. Amsler grid is invented by……… REFRACTION DEPARTMENT-CBE

516 Ans :Maricamsler 129. Glaucoma last stage is called --------------- Ans : Temporal Island of vision 130. ……. are used in field test. Ans : 4 colours 131. Neuro patient tested by…….. Ans : Red object 132. Retina patient tested by……… Ans : Green Object 133. Glaucoma patient tested by……… Ans : Blue Object 134. All patients tested by………. Ans : White object 136. …………… Patient affected by central cecal scotoma. Ans : Toxic, nutritional , smoking 138. Types of arcute scotoma are ………… Ans : Superior Arcute Scotoma And Inferior Arcute Scotoma III.TRUE OR FALSE : 1.TheAmsler grid test, determines the presence and location of defects in the peripheral portion of the visual field

517 Ans :False 2.Bitemporal hemianopia occurs in lesion of optictract. Ans :False 3. The visual field defect occurs due to lesion in the Optic nerve Ans :False 4. In visual fields the superior field image falls on the superior retina and the inferior field image falls on the inferior retina Ans :False 5.The lesions before the optic chiasm causes Binocular vision defect Ans :False 6. Bjerrum screen is easy to maintain Ans :True 7. Bjerrum screen is purely subjective Ans :True 8. There are no photoreceptors in optic never head Ans :True 9. Faded pinheads can be used for examination Ans :False 10. Patient will feel pain during Bjerrum examination. Ans :False REFRACTION DEPARTMENT-CBE

518 11.In Centro cecal scotoma the blind spot is enlarged and central macular is not affected Ans :False IV. MATCH THE FOLLOWING : 1. Amsler’sGrid - CentralScotoma - Bjerrum’sscreen 2. Centralfields - Optic tract Homonymous 3. - Meyer’s Loop - Lateral optic chiasm Hemianopia - Optic Nerve 4. Quadrantanopia - Mid line Optic chiasma 5. Binasal hemianopia - central cecal scotoma - 3cm 6. Anopia - - Bitemporal Hemianopia - Central scotoma Bitemporal - Total blind 7. - Bjerrum's screen - Tubular field hemianopia - Central scotoma - Blind spot 8. Optic chaisma - Bitemporalheminaopia - Humphery field anlyser 9. Amsler grid - 330mm 10. Optic nerve 11. Optic neuritis 12. Orbital part 13. Central fields 14. Retinitispigmentosa 15. Amsler's grid 16. Optic disc 17. Chiasmal defect 18. Acutomatedperimetry 19. Perimeters

519 20. Traquair's - Island of vision 21. Superior side - 60º to 70º 22. Inferior side - 70º to 80º 23. Visual field - Simultaneously visible 24. The end organ - Rods and cones 25. Positivescotoma - Central scotoma 26. Negative scotoma - Blind spot enlargement 27. Depression - Abnormal visual fields 28. Contraction - Sector 29. Kineticperimetry - Goldmann'sperimetry 30. Tangent screen - Bjerrum screen 31. Confrontation method - 2 to 3 feet 32. 16inch - Amsler grid 33. Isopter - 1mm 34. 15º temporal - Blindspot 35. Occipital cortex - Visual cortex 36. Central scotoma - Involving fixation 37. The central field - 30º radius of fixation V. GIVE THE REASON : 1.Why visual field test is important in glaucoma patient? Ans :To correlate the anatomical finding with the functional assessment 2.The fovea is always on temporal side of the optic nerve head? REFRACTION DEPARTMENT-CBE

520 Ans :The fovea is always on the Temporal / Lateral side of the nerve head of each eye 3. Bjerrum screen is easy to maintain Ans :There is no need for sterilization, it is not breakable so easy to clean 4. Bjerrum screen is purely subjective Ans :During the examination patient should give right feedback of what they are seeing. Ifthe patient gives wrong feedback then the result goes wrong. VI. TWO MARK QUESTIONS : Page no : 78 ( Manual ) Page no : 78 ( Manual ) 1.What are the three basic defects of visual field? Page no : 80 ( Manual ) 2.How many types of scotoma? Page no : 76 ( Manual ) 3.How many types of perimetry Page no : 76 ( Manual ) 4.Define physiological blind spot 5.Definetraquir concept

6.Write the parts of visual pathway 521 7.Write about the type of visual field 8.Define contraction Page no : 78 ( Manual ) 9.Define scotoma Page no : 78 ( Manual ) 10.How many types of scotoma Page no : 78 ( Manual ) 11.Write about the glaucoma field defect Page no : 78 ( Manual ) 12.Defineperimetry Page no : 78 ( Manual ) 13.Write about the confrontation method Page no : 79 ( Manual ) 14.Write about the tangent screen Page no :80 ( Manual ) 15.Define -Amsler grid Page no : 81 ( Manual ) Page no : 81 ( Manual ) Page no : 82 ( Manual ) REFRACTION DEPARTMENT-CBE

522 16.Write about automated perimeter 17.What is the principle of visual pathway? Page no : 83 ( Manual ) Page no : 77 ( Manual ) VII. FIVE MARK QUESTIONS : 1.Explain about the normal monocular or binocular visual field Page no : 76 2.Explain about the visual pathway Page no : 77 ( Manual ) 3.Explain about the glaucoma field defect 4.Explained about the perimetry Page no : 79 ( Manual ) Page no : 80 ( Manual ) VIII. DRAWING : 1. Draw the visual pathway Page no : 77 ( Manual ) 2. Draw the glaucoma field defect Page no :80 ( Manual ) 3.RightTemporalHemianopia

4.Arcute scotoma 523 5.RE Homonymous Heminopia Page no : 78 ( Manual ) Page no : 78 ( Manual ) 6.Macula spring Macula Spiliting Page no : 78 ( Manual ) Page no : 78 ( Manual ) IX.ENGLISH TO TAMIL : 1. Binocular field - தோளலதநாக்கிபுலம் 2. Principle - தகாள்ளக 3. scotoma - பார்ளவபரப்புஎல்ளலயில்ஒருபகுேிசரியாகதேரி யாைல்இருத்ேல் 4. Abnormal - அசாோரணைாக ஒருபக்கபார்ளவஇழப்பு 5. Hemianopic - 6. - தைாேல் Confrontation இயக்கலியல் துளற 7. Kinetic - தவற்றுபுள்ளி 8. Sector - 9. Blind spot - REFRACTION DEPARTMENT-CBE

524 10. Visual - காட்சிபாளே pathway உைலியல் 11. Physiological - X. JUMBING WORDS : 1.–B—L-TE - ABSOLUTE 2.T-A-U-I-S - TRAQUAIRS 3. M-DU—ED - MODULATED 4. F-S-U-E - FISSURE 5. –OU-L-ING - DOUBLING XI. UNSCRAMBLE WORDS : 1.SEITRNCCEEITCI - ECENTRICITIES 2.TSOOCICP - SCOTOPIC 3.SSIONPGROORE - PROGRESSION 4.AMEIHPCION - HEMIANOPIC 5.GRCUUOONS - CONGROUS XII.CORRECT SENTENCE :

1. Hemianopic defect respecting the horizontalmeridian 525 2.Binasalhemianopic is parts defect the optic chaisma 3. Scotoma is area of increasing visual sensitivity Ans : Vertical Ans :Bitemporal Ans : Reduced Work Sheet 1.Write about the basic field defects which we see during visual field testing? REFRACTION DEPARTMENT-CBE

526 2.Explain about the types of scotoma? 3.Write about any 3 basic terminology in visual field defect? 4.Write about the field defects in lesions affecting various parts of the visual pathway.

527 5.What are the methods to assess the visual field. 6.Explain about the DematoCampimeter. 7.Write about the automated perimetry REFRACTION DEPARTMENT-CBE

528 8.Write about the types of depression in visual field? 9.Explain about the types of relative scotoma: 10.Write about specific defects suggestive of glaucoma: 11. Which types of glass will we prescribe in a hemianopic patient and Why?

529 12.What is the reason for bitemporal or binasal hemianopia when a part of chaisma is affected? REFRACTION DEPARTMENT-CBE

530 CHAPTER 10 ULTASONOGRAPHY (A SCAN)

531 CHAPTER 10 ULTASONOGRAPHY (A SCAN) CONTENTS Reflectivity Velocity of sound REFRACTION DEPARTMENT-CBE

532 IOL power with biometry Formula Ophthalmometer Principle Procedure Recording I.ABBREVIATION : 1. AL - Axial Length 2. KR - Keratometry Reading 3. IOL - Intra Ocular Lens 4. SRK - Sanders, Retzlaff, Kraft 5. A-scan - Amplitude Of Scan 6. B-scan - Bio Microscopy 7. ACD - Anterior Chamber Depth 8. D - Diopter 9. m/s - Meters Per Second 10. WR - With The Rule 11. AR - Against The Rule 12. OBL - Oblique 13. MCAR - Mires Clear And Regular 14. MIAD - Mires Irregular And Distorted 15. AL - Axial Length

533 16. B&L - Baush&lomb 17. PC - Posterior Chamber 18. AC - Anterior Chamber 19. BC - Biconvex Power 20. PSCC - Posterior Sub Capsular Cataract 21. PCO - Posterior Capsular Opacity 22. SICS - Small Incision Cataract Surgery 23. ECCE - Extra Capsular Cataract Extraction 24. MICS - Minimal Incision Cataract Surgery 25. CCT - Central Corneal Thickness 26. PCI - Partial Coherence Interferometry 27. SSOCI Swept Source Optical Coherence - 28. LRL 29. LRI Interferometry 30. CC - Lunar Robatic Lander 31. LT - Limbal Relaxing Incision 32. SD - Corneal Curvature 33. WTW - Lens Thickness - Standard Deviation - White To White II. CHOOSE THE BEST ANSWER : 1. When performing a- scan biometry a one diopters IOL power error could result from an axial length ……….. A] 0.33mm B] 0.03mm C] 33cm REFRACTION DEPARTMENT-CBE

534 Ans : A] 0.33mm 2. The strength of an echo is indicated by the height of the spike …… A] A-Scan B] B-Scan C] CT-Scan Ans : A] A-Scan 3. Axial length &keratometry formula to determine---------- A] Axial Length B] Curvature Of The Cornea C]IOL Power Ans : C]IOL Power 4. IOL replaces natural lens of eye after ---------- A] A-Scan Biometry B] IOL Power Calculation C] Cataract Surgery Ans : C] Cataract Surgery 5. Keratometry determines corneal curvature by measuring the size of a reflected -- --------- A] Purkinje Image B] Mire C] Corneal Image Ans : B] Mire 6. The first spike represents the probe tip as it comes into contact with the ------- A] Aqueous Humor B] Anterior Surface Of The Lens C] Cornea

535 Ans : C] Cornea 7. -------- axis passes through cornea and retina distance in the normal eye A] Optical Axis B] Visual Axis C] Reflectivity Ans : A] Optical Axis 8. Corneal compression is due to ------------ A] Increase The Axial Length B] Decrease The Axial Length C] Increase The Corneal Curvature Ans : B] Decrease The Axial Length 9. Ultra sound travel at high speed through -------&materials containing high water content A] Cornea &Lens B] Cornea &Aqueous C] Water Ans : C] Water 10. The speed of ultra sound through vitreous is --------- A] 153.3 m/s B] 15.30 m/s C] 1532 m/s Ans : C] 1532 m/s 11. Biometric information is fed into the -------- to calculate the IOL power A] One Formula B] Variety Of Formula C] Two Formula REFRACTION DEPARTMENT-CBE

536 Ans : B] Variety Of Formula 12. A Pseudophakia as can measure an eye that ……… A] Does Not Have A Lens B] Has An IOL Plane C] A, B Ans : B] Has An IOL Plane 13. Velocity of sound in cataract us lens is .............. A] 1640m/s B] 1629m/s C] 1532m/s Ans : B] 1629m/s 14. SRK II formula is......... .... A] p= 1336(4r-d)/ (a-d) (4r-d) B] a-(2.5l – 0.9 k) C] a-(2.5l +0.9k) Ans : B] a-(2.5l – 0.9 k) 15. Optical axis of the eye distance from.......... to.. ......... A] Cornea-Lens B] Cornea –Retina C] Lens -Retina Ans : B] Cornea –Retina 16. A normal k-reading value............. a] 42.00 to 43.00d b] 42.50to 46.00d c] 43.00 to 45.00d Ans : c] 43.00 to 45.00d 17. A normal axial length value................ A] 24.00 to 25.00 mm B] 23.00 to 25.00mm C] 23.00 to 24.00mm Ans : C] 23.00 to 24.00mm

537 18. A scan biometry is also called.................. measurement A] K-Reading B] Axial Length C] IOL Power Ans : B] Axial Length 19. Post lasik patient used formula........... A] Haggis Suite B] SRK- T C] Hoffer Q Ans : A] Haggis Suite 20. Short eye ball used formula........... A] Haggis Suite B] SRK-T C] Hoffer Q Ans : C] Hoffer Q 21. Long eye ball used formula.............. A] Haggis Suite B] SRK –T C] Hoffer Q Ans : B] SRK –T 22. Velocity of sound cornea................. A] 1640 m/s B] 1532 m/s C] 1629 m/s Ans : A] 1640 m/s 23. Velocity of sound normal lens............. REFRACTION DEPARTMENT-CBE

538 A] 1532 m/s B] 1640 m/s C] 1629 m/s Ans : B] 1640 m/s 24. Velocity of sound aqueous................ A] 1532 m/s B] 1640m/s C] 1629 m/s Ans : A] 1532 m/s 25. Velocity of sound cataract us lens ..................... A] 1532 m/s B] 1640 m/s C] 1629 m/s Ans : C] 1629 m/s 26. Velocity of sound vitreous................. A] 1532 m/s B] 1640 m/s C] 1629 m/s Ans : A] 1532 m/s 27. Velocity of sound silicon ................... A] 1532 m/s B] 1640 m/s C] 900 m/s Ans : C] 900 m/s 27. ---------- image avoids problems from eye movements A] Double Image B] Single Image C] Triple Image Ans : A] Double Image 28.Keratometer measures only the central---------- of the corneal diameter

539 A]3mm B] 6mm C] 5mm Ans : A]3mm 29. Optical axis of the eye distance from to.................. A] Cornea Apex Fovea B] Cornea Retina C] Cornea To Vitreous Ans : A] Cornea Apex Fovea 30. It measure the size of image reflected from the corneal surface because cornea acts as…........ A] Concave Mirror B] Convex Mirror C] Double Prism Ans : B] Convex Mirror 31. In a cataractous lens, the speed of sound ………. A] Decreases B] Increases C]. Does Not Change Ans : A] Decreases 32 .For a normal eye, the number of spikes seen in A scan is ………. A]5 B]4 C]3 Ans : B]4 33. Probe tip at a given frequency of approximately................... REFRACTION DEPARTMENT-CBE

540 B] 5 Mhz C] 20 Mhz Ans : A] 10 Mhz A] 10 Mhz C] Axis Of Lens 34. Axial length means.................... Ans : B] Axial Length A] Anterior Lens B] Axial Length C] 5 Ans : C] 5 35.In Immersion mode on gain of spike ................. A] 3 B] 4 C] 3 Ans : A] 4 36. In Immersion mode off gain of spike ............ A] 4 B] 5 37. Keratometry provides an --------- quantitative measurement of corneal astigmatism A] Subjective B] Objective C] Manual Ans : B] Objective 38. Keratometry is also helpful in determining the appropriate fitting of---------

541 A] Contactlens B] Cornealcurvature C][A] & [B] Ans : C][A] & [B] 39. The measurement of the curvature of the anterior corneal surface is done by using the first -------- A] Central Image B] Purkinje Image C] Fleshier Ring Ans : B] Purkinje Image III. FILL IN THE BLANKS: 1.A-scan biometry is called-------- Ans : axial measurement 2.Axial length measurement is combined with------ Ans :keratometry 3.--------- probe projects a thin sound beam that travels through liquid or tissue Ans : A-scan 4.--------- representing these reflections appear at their corresponding position along the baseline Ans : spikes 5.---------is the distance from the corneal apex to the fovea Ans : optical axis REFRACTION DEPARTMENT-CBE

542 6. ----------comes into contact with the cornea either directly or through a liquid method Ans : A-scan probe 7.--------result in an artificial shortening of the axial eye length Ans : compression 8.In A-scan biometry, one thin&-------- is emitted from the probe tip at a given frequency of approximately 10 MHz Ans : parallel sound beam 9.--------is essentially consists of a keratometric reading, axial length anterior chamber depth Ans : biometry 10.Various theoretical formulas derived from the -------optics Ans : geometrical 11.----------is the measurement of a patient’s central corneal curvature Ans :keratometry 12.Keratometry provides an objective, quantitative measurement of ------- Ans : corneal curvature 13.In Hirschberg test, the angle of manifest squint is estimated from the position of the …………reflection in the squinting eye Ans : corneal

543 14. In a keratometer, doubling of images avoids problems from …………….. Movements Ans : eye 15.In keratometer cornea acts as a------------- mirror Ans : convex 16.Ophthalmic ultrasonography uses the ------ or ------ Ans : reflection, high frequency 17.------ to define the outlines of ocular and orbital structure Ans : sound waves 18.Partial optical coherence tomography is the principle of ------- Ans : A-scan 19. ------is a one dimensional display Ans : A-scan 20.Normal BC-power --------- Ans : 20.0d to22.0d 21.Normal mode to pseudoapakic mode variation --------- Ans : 10mm to 20mm REFRACTION DEPARTMENT-CBE

544 22.------myopia patient axial length is normal Ans : Lenticular 23.Cataract with astigmatism patient is advised to use -------- Ans :Toric lens 24. A scan means ……… Ans : Amplitude of scan 25.………..uses the reflection or echoes of high frequency sound waves to define the outlines of ocular and orbital structures. Ans : Ultrasonography 26.Ultra sound procedures are divided into two types ………… Ans : 1. a scan ultrasonography 2. b scan ultrasonography 27.A scan is a ……….. Ans : One dimensional display 28.A scan probe projects a thin sound beam that travels through …… Ans : Liquid or tissue 29.Optical axis of the eye distance from …… Ans : Corneal apex to fovea

545 30.An ultra sound beam will not pass through in……….. Ans : Foreign body 31. Corneas compression caused by excessive pressure from the probe will cause ………..of the axial length. Ans : Artificial shortening 32.4mm compression error can result in ………. error in the calculated IOL power. Ans : 1diapter 33.The radius of cornea curvature ………………. Ans : 7.8mm 34.A scan probe tip at a given frequency of approximately …… Ans : 10 MHz 35.Biometry essentially consists of a …… and ultra-sonic measurement of ………. Ans :Keratometric reading , Axial length and anterior chamber depth 36.Binkhorstformula ……………. Ans : p=1336 (4r-d)/(a-d)(4r-d) 37. Formula ………….. Ans : SRK I, SRK II P= A-(2.5l-0.9k) REFRACTION DEPARTMENT-CBE

546 38. SRK t formula used…………. Ans : Above 22.0mm AXL 39. Hypermetropic over correction …………… Ans : Consecutive myopia 40. Myopic under correction ………. Ans : Consecutive hypermetropia 41.Silicon oil formula ……………… 42.Lasik formula ………………. Ans : 0.71 x present axial length 43.A scan inventer ……………… Ans :Prek – 1.135 (pre k – post k) Ans : Louis kraft 44.IOL invented by ………. Ans : Harold Ridley 45.Cataract invented by ……….. Ans :Sushruta 46.The central thickness of lens in ………… Ans : 3.6mm

547 47.Refractive index of the lens………. Ans : 1.42 48.ACD normal value is…………… Ans : AC 2.5mm to 3.5mm 49.Anterior posterior diameter of eye ……... Ans : 23mm vertical, horizontally 23.50mm 50.The cornea diameter in12mm……… Ans : Horizontal 11.5mm vertically 51. The cornea thickness center ………….peripheral 52.The refractive index of cornea……….. Ans : 0.50mm ,1mm 53.The cornea dioptric power…………… Ans : 1.37 54.Wrong IOL calculation formula …………… 55.Restore is………………… Ans : +43.0ds to 45.0ds Ans : p-(exert) Ans : Multifocal lens REFRACTION DEPARTMENT-CBE

548 56.Probe tip rays ……………… Ans :LyzoCryzal 57.IOL calculation used formula is………… Ans : SRK I, SRK II, Haigis Suite, Hoffer Q 58.Keratometer size of image depends on ,………… Ans : 1. The distance of the object 2.The curvature of the cornea 59.Vertical meridian is more curvature then horizontal is called…………… Ans : with rule astigmatism 60.Horizontal meridian is more curved than vertical is called……………… Ans : Against rule astigmatism 61.Normal base curve value…………………. Ans : 7.5 62.Normal keratometer value………… Ans : +44.0d to +45.0ds 63.Normal axial length………………… Ans : 23 to 24mm

549 64.RD patient have …………………… Ans : decreased axial length 65.Keratometer measured the ……… Ans : curvature of the central part of the cornea 66.Keratometer other name……………… Ans :Ophthalmo meter 67. Relationship between radius of curvature and dioptric power of the cornea formula------------------ Ans : D = n-1/r 68. Keratometer measures only the…… Ans : Central 3mm Of The Cornea Diameter 69.Flat cornea is…………. Ans : Below 40 D 70.Steep cornea…………………………. Ans : Above 50 D 71.Above 52…………… Ans : +1.25Ds power is neutrilize add +6.0d REFRACTION DEPARTMENT-CBE

550 72.Below 36 ……… Ans : -1.25Ds power is neutrilize less -6.0Ds 73.43.00x180, 45.50x90 …… Ans : with rule astigmatism 74. 45.50x180, 44.00x90 ............................ Ans : against rule astigmatism 75. Keratometer invented by .. Ans : Hellman von Helmholtz in 1851 76.Base curve value……… Ans : 6.4 to 9.4 77.Corneal calculation using radius of curvature formula …..…. Ans : D=(n-1)/r 78. ………… in silicon oil injection patient Ans : Increase the axial length 79.IOL master company name………………… Ans : Zeiss 80.Binkhorst formula…………………… Ans : P=1336 (4r-d)/(a-d) (4r-d)