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What Is Amblyopia?

  • Nigel W. Daw

Abstract

Amblyopia is defined primarily as a loss of acuity. In anisometropia, grating acuity, Snellen (optotype) acuity, and vernier acuity are degraded in proportion to each other. In strabismus, Snellen and vernier acuity are degraded more than grating acuity. The main problem in both cases is loss of binocular function, producing loss of stereoscopic vision. A number of other properties are also affected. There is uncertainty about the location of an object in space, a reduction in the ability to detect shapes, deficits in motion and direction perception, less ability to track several objects at once, reduced counting ability, and suppression of the image in one eye by the image in the other, to avoid the diplopia and confusion arising when the two eyes are looking in different directions. Some of these deficits are seen in the fellow as well as the amblyopic eye and in binocular viewing. There are also deficits in eye movements: poor fixation, a longer latency for saccades, inability to follow an object moving away from the nose smoothly, and slow inaccurate movements in visually guided reaches. These particularly affect reading so that an amblyope’s reading speed in both eyes is one-half to three-quarters of that of a normal person.

Keywords

Contrast Sensitivity Binocular Rivalry Spatial Uncertainty Snellen Acuity Binocular Interaction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. Aaen-Stockdale C, Ledgeway T, Hess RF (2007) Second-order optic flow deficits in amblyopia. Invest Ophthalmol Vis Sci 48:5532–5538PubMedCrossRefGoogle Scholar
  2. Barrett BT, Pacey IE, Bradley A, Thibos LN, Morrill P (2003) Nonveridical visual perception in human amblyopia. Invest Ophthalmol Vis Sci 44:1555–1567PubMedCrossRefGoogle Scholar
  3. Birch E (2013) Amblyopia and binocular vision. Prog Retin Eye Res 33:67–84PubMedCrossRefGoogle Scholar
  4. Bouma H (1970) Interaction effects in parafoveal letter recognition. Nature 226:177–178PubMedCrossRefGoogle Scholar
  5. Bradley A, Freeman RD (1981) Contrast sensitivity in anisometropic amblyopia. Invest Ophthalmol 21:467–476Google Scholar
  6. Daw NW (1962) Why after-images are not seen in normal circumstances. Nature 196:1143–1145PubMedCrossRefGoogle Scholar
  7. Demanins R, Wang YZ, Hess RF (1999) The neural deficit in strabismic amblyopia: sampling considerations. Vis Res 39:3575–3585PubMedCrossRefGoogle Scholar
  8. Ellemberg D, Lewis TL, Maurer D, Brar S, Brent HP (2002) Better perception of global motion after monocular than after binocular deprivation. Vis Res 42:169–179PubMedCrossRefGoogle Scholar
  9. Enoch JM, Berger R, Birns R (1970) A static perimetric technique believed to test receptive field properties: extension and verification of the analysis. Doc Ophthalmol 29:127–153PubMedCrossRefGoogle Scholar
  10. Fischer J, Whitney D (2011) Object-level visual information gets through the bottleneck of crowding. J Neurophysiol 106:1389–1398PubMedCrossRefGoogle Scholar
  11. Flom MC, Bedell HE (1985) Identifying amblyopia using associated conditions, acuity, and nonacuity features. Am J Optom Physiol Opt 62:153–160PubMedCrossRefGoogle Scholar
  12. Flom MC, Weymouth FW, Kahneman D (1963) Visual resolution and contour interaction. J Opt Soc Am 53:1026–1032PubMedCrossRefGoogle Scholar
  13. Freeman AW, Nguyen VA, Jolly N (1996) Components of visual acuity loss in strabismus. Vis Res 36:765–774PubMedCrossRefGoogle Scholar
  14. Gstalder RJ, Green DG (1971) Laser interferometric acuity in amblyopia. Journal Pediatr Ophthalmol Strabismus 8:251–256Google Scholar
  15. Harrad R (1996) Psychophysics of suppression. Eye 10:270–273PubMedCrossRefGoogle Scholar
  16. Hayward J, Truong G, Partanen M, Giaschi D (2011) Effects of speed, age, and amblyopia on the perception of motion-defined form. Vis Res 51:2216–2223PubMedCrossRefGoogle Scholar
  17. Hess RF (1977) On the relationship between strabismic amblyopia and eccentric fixation. Br J Ophthalmol 61:767–773PubMedCrossRefGoogle Scholar
  18. Hess RF, Daw NW (2009) Amblyopia. In: Levin LA, Albert DM (eds) Ocular Disease: Mechanisms and Management. Saunders Ltd., New YorkGoogle Scholar
  19. Hess RF, Holliday IE (1992) The spatial localization deficit in amblyopia. Vis Res 32:1319–1339PubMedCrossRefGoogle Scholar
  20. Hess RF, Jacobs RJ (1979) A preliminary report of acuity and contour interaction across the amblyope's visual field. Vis Res 19:1403–1408PubMedCrossRefGoogle Scholar
  21. Hess RF, Pointer JS (1985) Differences in the neural basis of human amblyopia: the distribution of the anomaly across the visual field. Vis Res 25:1577–1594PubMedCrossRefGoogle Scholar
  22. Hess RF, Campbell FW, Greenhalgh T (1978) On the nature of the neural abnormality in human amblyopia; neural aberrations and neural sensitivity loss. Pflugers Arch 377:201–207PubMedCrossRefGoogle Scholar
  23. Hess RF, Field DJ, Watt RJ (1990) The puzzle of amblyopia. In: Blakemore C (ed) Vision: coding and efficiency. Cambridge University Press, Cambridge, UKGoogle Scholar
  24. Hess RF, Wang YZ, Demanins R, Wilkinson F, Wilson HR (1999) A deficit in strabismic amblyopia for global shape detection. Vis Res 39:901–914PubMedCrossRefGoogle Scholar
  25. Hess RF, Dakin SC, Tewfik M, Brown B (2001) Contour interaction in amblyopia: scale selection. Vis Res 41:2285–2296PubMedCrossRefGoogle Scholar
  26. Hess RF, Barnes G, Dumoulin SO, Dakin SC (2003a) How many positions can we perceptually encode, one or many? Vis Res 43:1575–1587PubMedCrossRefGoogle Scholar
  27. Hess RF, Pointer JS, Simmers A, Bex PJ (2003b) Border distinctness in amblyopia. Vis Res 43:2255–2264PubMedCrossRefGoogle Scholar
  28. Ho CS, Giaschi DE (2007) Stereopsis-dependent deficits in maximum motion displacement in strabismic and anisometropic amblyopia. Vision Res 47 (21):2778–2785PubMedCrossRefGoogle Scholar
  29. Hubel DH, Wiesel TN (1960) Receptive fields of optic nerve fibres in the spider monkey. J Physiol 154:572–580PubMedGoogle Scholar
  30. Husk JS, Farivar R, Hess RF (2012) Amblyopic deficits in processing structure-from-motion. J Vis 12:4PubMedCrossRefGoogle Scholar
  31. Irvine SR (1948) Amblyopia ex anopsia. Observations on retinal inhibition, scotoma, projection, light difference discrimination and visual acuity. Trans Am Ophthalmol Soc 66:527–575Google Scholar
  32. Jeffrey BG, Wang YZ, Birch EE (2004) Altered global shape discrimination in deprivation amblyopia. Vis Res 44:167–177PubMedCrossRefGoogle Scholar
  33. Kanonidou E, Proudlock FA, Gottlob I (2010) Reading strategies in mild to moderate strabismic amblyopia: an eye movement investigation. Invest Ophthalmol Vis Sci 51:3502–3508PubMedCrossRefGoogle Scholar
  34. Katz B, Sireteanu R (1990) The Teller acuity card test: a useful method for the clinical routine? Clin Vis Sci 5:307–323Google Scholar
  35. Lai XJ, Alexander J, He M, Yang Z, Suttle C (2011) Visual functions and interocular interactions in anisometropic children with and without amblyopia. Invest Ophthalmol Vis Sci 52:6849–6859PubMedCrossRefGoogle Scholar
  36. Le Grand R, Mondloch CJ, Maurer D, Brent HP (2001) Neuroperception. Early visual experience and face processing. Nature 410:890PubMedCrossRefGoogle Scholar
  37. Levi DM (2007) Image segregation in strabismic amblyopia. Vis Res 47:1833–1838PubMedCrossRefGoogle Scholar
  38. Levi DM, Klein S (1982) Hyperacuity and amblyopia. Nature 298:268–270PubMedCrossRefGoogle Scholar
  39. Levi DM, Klein SA (1983) Spatial localization in normal and amblyopic vision. Vis Res 23:1005–1017PubMedCrossRefGoogle Scholar
  40. Levi DM, Klein SA (1985) Vernier acuity, crowding and amblyopia. Vis Res 25:979–991PubMedCrossRefGoogle Scholar
  41. Levi DM, Klein SA (1986) Sampling in spatial vision. Nature 320:360–362PubMedCrossRefGoogle Scholar
  42. Levi DM, Klein SA (1990a) Visual acuity in strabismic and anisometropic amblyopia: a tale of two syndromes. Ophthalmol Clin North Am 3:289–301Google Scholar
  43. Levi DM, Klein SA (1990b) Equivalent intrinsic blur in spatial vision. Vis Res 30:1971–1993PubMedCrossRefGoogle Scholar
  44. Levi DM, Polat U (1996) Neural plasticity in adults with amblyopia. Proc Nat Acad Sci U S A 93:6830–6834CrossRefGoogle Scholar
  45. Levi DM, McKee SP, Movshon JA (2011) Visual deficits in anisometropia. Vis Res 51:48–57PubMedCrossRefGoogle Scholar
  46. Levi DM, Song S, Pelli DG (2007) Amblyopic reading is crowded. J Vis 7(2):21–17Google Scholar
  47. Lewis TL, Ellemberg D, Maurer D, Wilkinson F, Wilson HR, Dirks M, Brent HP (2002) Sensitivity to global form in glass patterns after early visual deprivation in humans. Vis Res 42:939–948PubMedCrossRefGoogle Scholar
  48. Lions C, Bui-Quoc E, Seassau M, Bucci MP (2013) Binocular coordination of saccades during reading in strabismic children. Invest Ophthalmol Vis Sci 54:620–628PubMedCrossRefGoogle Scholar
  49. Maurer D, Lewis TL (1993) Visual outcomes after infantile cataract. In: Simons K (ed) Early visual development, normal and abnormal. Oxford University Press, New York, pp 454–484Google Scholar
  50. Maxwell GF, Lemij HG, Collewijn H (1995) Conjugacy of saccades in deep amblyopia. Invest Ophthalmol Vis Sci 36:2514–2522PubMedGoogle Scholar
  51. McKee SP, Westheimer G (1978) Improvement in vernier acuity with practice. Percept Psychophys 24:258–262PubMedCrossRefGoogle Scholar
  52. McKee SP, Levi DM, Movshon JA (2003) The pattern of visual deficits in amblyopia. J Vis 3:380–405PubMedCrossRefGoogle Scholar
  53. Niechwiej-Szwedo E, Goltz HC, Chandrakumar M, Hirji ZA, Wong AMF (2010) Effect of anisometropic amblyopia in visuomotor behavior, I: saccadic eye movements. Invest Ophthalmol Vis Sci 51:6348–6354PubMedCrossRefGoogle Scholar
  54. Niechwiej-Szwedo E, Kennedy SA, Colpa L, Chandrakumar M, Goltz HC, Wong AM (2012) Effects of induced monocular blur versus anisometropic amblyopia on saccades, reaching, and eye-hand coordination. Invest Ophthalmol Vis Sci 53:4354–4362PubMedCrossRefGoogle Scholar
  55. Ono S, Das VE, Mustari MJ (2012) Conjugate adaptation of smooth pursuit during monocular viewing in strabismic monkeys with exotropia. Invest Ophthalmol Vis Sci 53:2038–2045PubMedCrossRefGoogle Scholar
  56. Pelli DG, Tillman KA (2008) The uncrowded window of object recognition. Nat Neurosci 11:1129–1135PubMedCrossRefGoogle Scholar
  57. Pelli DG, Robson JG, Wilkins AJ (1988) The design of a new letter chart for measuring contrast sensitivity. Clin Vis Sci 2:187–199Google Scholar
  58. Pelli DG, Levi DM, Chung STL (2004) Using visual noise to characterize amblyopic letter identification. J Vis 4:904–920PubMedCrossRefGoogle Scholar
  59. Pugh M (1962) Amblyopia and the retina. Br J Ophthalmol 46:193–211PubMedCrossRefGoogle Scholar
  60. Rouse MW, Tittle JS, Braunstein ML (1989) Stereoscopic depth perception by static stereo-deficient observers in dynamic displays with constant and changing disparity. Optom Vis Sci 66:355–362PubMedCrossRefGoogle Scholar
  61. Schor CM (1977) Visual stimuli for strabismic suppression. Perception 6:583–588PubMedCrossRefGoogle Scholar
  62. Secen J, Culham J, Ho C, Giaschi D (2011) Neural correlates of the multiple-object tracking deficit in amblyopia. Vis Res 51:2517–2527PubMedCrossRefGoogle Scholar
  63. Sengpiel F, Jirmann KU, Vorobyov V, Eysel UT (2006) Strabismic suppression is mediated by inhibitory interactions in the primary visual cortex. Cereb Cortex 16:1750–1758PubMedCrossRefGoogle Scholar
  64. Sharma V, Levi DM, Klein SA (2000) Undercounting features and missing features: evidence for a high-level deficit in strabismic amblyopia. Nat Neurosci 3:496–501PubMedCrossRefGoogle Scholar
  65. Simmers AJ, Ledgeway T, Hess RF, McGraw PV (2003) Deficits to global motion processing in human amblyopia. Vis Res 43:729–738PubMedCrossRefGoogle Scholar
  66. Simmers AJ, Ledgeway T, Hutchinson CV, Knox PJ (2011) Visual deficits in amblyopia constrain normal models of second-order motion processing. Vis Res 51:2008–2020PubMedCrossRefGoogle Scholar
  67. Sireteanu R, Fronius M (1981) Naso-temporal asymmetries in human amblyopia: consequence of long-term interocular suppression. Vis Res 21:1055–1063PubMedCrossRefGoogle Scholar
  68. Sireteanu R, Fronius M (1989) Different patterns of retinal correspondence in the central and peripheral visual field of strabismics. Invest Ophthalmol Vis Sci 30:2023–2033PubMedGoogle Scholar
  69. Sireteanu R, Fronius M, Singer W (1981) Binocular interaction in the peripheral visual field of humans with strabismic and anisometropic amblyopia. Vis Res 21:1065–1074PubMedCrossRefGoogle Scholar
  70. Stuart JA, Burian HM (1962) A study of separation difficulty. Am J Ophthalmol 53:471–477PubMedGoogle Scholar
  71. Suttle CM, Melmoth DR, Finlay AL, Sloper JJ, Grant S (2011) Eye-hand coordination skills in children with and without amblyopia. Invest Ophthalmol Vis Sci 52:1851–1864PubMedCrossRefGoogle Scholar
  72. Thompson B, Troje NF, Hansen BC, Hess RF (2008) Amblyopic perception of biological motion. J Vis 8:22, 21–14PubMedCrossRefGoogle Scholar
  73. Tripathy SP, Cavanagh P (2002) The extent of crowding in peripheral vision does not scale with target size. Vis Res 42:2357–2369PubMedCrossRefGoogle Scholar
  74. Tychsen L, Richards M, Wong A, Foeller P, Bradley D, Burkhalter A (2010) The neural mechanism for Latent (fusion maldevelopment) nystagmus. J neuroophthalmol 30:276–283PubMedCrossRefGoogle Scholar
  75. Wang C, Waleszczyk WJ, Burke W, Dreher B (2007) Feedback signals from cat's area 21a enhance orientation selectivity of area 17 neurons. Exp Brain Res 182:479–490PubMedCrossRefGoogle Scholar
  76. Wilson HR (1991) Model of peripheral and amblyopic hyperacuity. Vis Res 31:967–982PubMedCrossRefGoogle Scholar
  77. Zhou J, Huang PC, Hess RF (2013) Interocular suppression in amblyopia for global orientation processing. J Vis 13(5):19, 1–14PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Nigel W. Daw
    • 1
  1. 1.BranfordUSA

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