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Annals of Ophthalmology

, Volume 33, Issue 2, pp 103–112 | Cite as

Mechanism of human accommodation as analyzed by nonlinear finite element analysis

  • Ronald A. Schachar
  • Andrew J. Bax
Original Article

Abstract

Results of nonlinear finite element analysis support the Schachar theory of accommodation and demonstrate that the long-held Helmholtz theory of accommodation is impossible.

Keywords

Spherical Aberration Crystalline Lens Ciliary Muscle Nonlinear Finite Element Analysis Central Thickness 
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.

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References

  1. 1.
    Young, T. On the mechanism of the eye. Philos Trans Roy Soc Lond. 1801;92:23–88.CrossRefGoogle Scholar
  2. 2.
    Tscherning M. Physiological Optics, Philadelphia, Pa: Keystone; 1904;160–189.Google Scholar
  3. 3.
    Fincham EF. Mechanism of accommodation. Br J Ophthalmol. 1937;8(suppl):5–80.Google Scholar
  4. 4.
    Ivanoff A. On the influence of accommodation on spherical aberration in the human eye: an attempt to interpret night myopia. J Opt Soc Am. 1947;37:730–731.Google Scholar
  5. 5.
    Kooman M, Tousey R, Scolnik R. The spherical aberration of the eye. J Opt Soc Am. 1949;39:370–376.CrossRefGoogle Scholar
  6. 6.
    von Helmholtz H. Uber die Akkommodation des Auges. Graefes Arch Clin Exp Ophthalmol. 1855;1:1–89.Google Scholar
  7. 7.
    Schachar RA. Cause and treatment of presbyopia with a method for increasing the amplitude of accommodation. Ann Ophhthamol. 1992;24:445–452.Google Scholar
  8. 8.
    Schachar RA. Zonular function: a new hypothesis with clinical implications. Ann Ophthalmol 1994;26:36–38.PubMedGoogle Scholar
  9. 9.
    Schachar RA, Anderson DA. The mechanism of ciliary muscle function. Ann Ophthalmol. 1995;27:126–132.Google Scholar
  10. 10.
    Schachar RA. Histology of the ciliary muscle-zonular connections. Ann Ophthalmol. 1999;31:10–17.Google Scholar
  11. 12.
    Schachar RA, Cudmore DP, Black TD. A revolutionary variable focus lens. Ann Ophthalmol. 1996;28:11–18.Google Scholar
  12. 13.
    Schachar RA, Cudmore DP, Black TD, et al. Paradoxical optical power increase of a deformable lens by equatorial stretching. Ann Ophthalmol. 1998;30:10–18.Google Scholar
  13. 14.
    Fisher RF. Elastic constants of the human lens capsule. J Physiol [Lond]. 1969;201:1–19.Google Scholar
  14. 15.
    van Alphen GWHM, Graebel WP. Elasticity of tissues involved in accommodation. Vision Res. 1991;31:1417–1438.PubMedCrossRefGoogle Scholar
  15. 16.
    Krag S, Olsen T, Andreassen TT. Biomechanical characteristics of the human anterior lens capsule in relation to age. Invest Ophthalmo Vis Sci. 1997;38:357–363.Google Scholar
  16. 17.
    Hogan MJ, Alvardo JA, Weddell JE. Histology of the Human Eye. Philadelphia, Pa: WB Saunders Co; 1971:667–673.Google Scholar
  17. 18.
    Duke-Elder S, Gloster J, Weale RA. The physiology of the eye and of vision. In: Duke-Elder S. ed., System of Ophthalmology Vol 4. London, England: Henry Kimpton: 1968:365–366.Google Scholar
  18. 19.
    Burd HJ, Judge SJ, Flavell MJ. Mechanics of accommodation of the human eye. Vision Res. 1999;39:1591–1595.PubMedCrossRefGoogle Scholar
  19. 20.
    Baughman RH, Dantas SO, Stafrom S, Zakhidov AA, Mitchell TB, Dubin DHE. Negative Poisson's ratios for extreme states of matter. Science. 2000;288:2018–2022.PubMedCrossRefGoogle Scholar
  20. 21.
    Chen JS, Pan C. A pressure projection method for nearly incompressible rubber hyperelasticity. Part I: Theory. J Appl Mech. 1996; 63:862–868.Google Scholar
  21. 22.
    Chen JS, Wu CT, Pan C. A pressure projection method for nearly incompressible rubber hyperelasticity. Part II: Applications. J Appl Mech. 1996;63:869–876.Google Scholar
  22. 23.
    Brown N. The change in shape, and internal form of the lens of the eye on accommodation. Exp Eye Res. 1973;15:441–459.PubMedCrossRefGoogle Scholar
  23. 24.
    Farnsworth PN, Shyne SE. Anterior zonular shifts with age. Exp Eye Res. 1979;28:291–297.PubMedCrossRefGoogle Scholar
  24. 25.
    McCulloch C. The zonule of Zinn: its origin, course, and its relation to neighboring structures. Trans Am Ophthalmol Soc. 1954; 52:525–585.PubMedGoogle Scholar
  25. 26.
    Brown N. The shape of the lens equator Exp Eye Res. 1974;19:571–576.PubMedCrossRefGoogle Scholar
  26. 27.
    ANSYS 5.6. User's Manual & Theory Reference. Cannonsburg, Pa: ANSYS Inc; 1999.Google Scholar
  27. 28.
    Born W, Wolf E. Principles of Optics. 4th ed. Oxford, England: Pergamon Press; 1970:161–163.Google Scholar
  28. 29.
    Zemax Optical Design Program: User's Guide. Version 9.0. Tucson, Ariz: Focus Software Inc; 2000.Google Scholar
  29. 30.
    Donders FO, On the Anomalies of Accommodation and Refraction of the Eye. London, England: New Sydenham Society; 1864:204–214.Google Scholar
  30. 31.
    van Alphen GWHM, Robinett SL, Macri FJ. Drug effects on ciliary muscle and choroid preparations in vitro. Arch Ophthalmol. 1962;68:111–123.Google Scholar
  31. 32.
    Fisher RF. The force of contraction of the humna ciliary muscle during accommodation. J Physiol. 1977;270:51–74.PubMedGoogle Scholar
  32. 33.
    Fukasaku H. The Correction of Presbyopia [film]. Seattle, Wash: American Society of Cataract and Refractive Surgery; May 1999.Google Scholar
  33. 34.
    Schachar RA, Tello C, Cudmore DP, et al. In vivo increase of the human lens equatorial diameter during accommodation. Am J Physiol (Regulatory Integrative Comp Physiol 40). 1996;271:R670-R676.Google Scholar
  34. 35.
    Schachar RA, Cudmore DP, Torti R, et al. A physical model demonstrating Schachar's hypothesis of accommodation. Ann Ophthalmol. 1994;26:4–9.PubMedGoogle Scholar
  35. 36.
    Emery JM, Paton D. Current Concepts in Cataract Surgery. St Louis, Mo. CV Mosby Co; 1976:182–189.Google Scholar
  36. 37.
    Streeten BW. Zonular apparatus. In: Jakobiec FA, ed. Ocular Anatomy, Embryology and Teratology. Philadelphia, Pa: Harper & Row Publishers; 1982:331–353.Google Scholar
  37. 38.
    Schachar RA, Huang T, Huang X. Mathematic, proof of Schachar's hypothesis of accommodation. Ann Ophthalmol 1993;25:5–9.PubMedGoogle Scholar
  38. 39.
    Ganem SP, Stubler S. The mechanism of human accommodation: an analytical mathematical model [abstract]. Presented at: American Society of Cataract and Refractive Surgery meeting; May 2000; Boston, Mass.Google Scholar
  39. 40.
    Neider MW, Crawford K, Kaufman PL, Bito LZ. In vivo videography of the rheusus monkey accommodative apparatus: age-related loss of ciliary muscle response to central stimulation. Arch Ophthalmol. 1990;108:69–74.PubMedGoogle Scholar
  40. 41.
    Koretz JF, Bertasso AM, Neider MW, True-Gabelt B, Kaufman PL. Slit-lamp studies of the Rhesus monkey eye. II. Changes in crystalline lens shape, thickness and position during accommodation and aging. Exp Eye Res. 1987;45:317–326.PubMedCrossRefGoogle Scholar
  41. 42.
    Wilson RS. Does the lens diameter increase or decrease during accommodation? Human accommodation studies: a new technique using infrared retro-illumination video photography and pixel unit measurements. Trans Am Ophthalmol Soc. 1997;95:261–270.PubMedGoogle Scholar
  42. 43.
    Le Grand Y. Optique Physiologique I. 2nd ed. Paris, France: Editions de la Revue D'Optoque; 1952:45.Google Scholar
  43. 44.
    Gullstrand A In: von Helmholtz H, ed. Physiological Optics, 3rd ed. Mineola, NY, Dover Publications; 1962:56,396.Google Scholar
  44. 45.
    Enoch JM, Hope GM. An analysis of retinal orientation. IV. Center of the entrace pupil and the center of convergence of orientation and directional sensitivity. Invest Ophthalmol. 1972;11:1017–1021.PubMedGoogle Scholar
  45. 46.
    Glasser A, Kaufman PL. The mechanism of accommodation in primates. Ophthalmology. 1999;106:863–872.PubMedCrossRefGoogle Scholar
  46. 47.
    Levy NS. The mechanism of accommodation in primates [letter]. Ophthalmology. 2000;107:625.PubMedCrossRefGoogle Scholar
  47. 48.
    Glasser A, Kaufman PL. The mechanism of accommodation in primates [letter]. Ophthalmology. 2000;107:626.CrossRefGoogle Scholar
  48. 49.
    Strenk SA, Semmlow JL, Strenk LM, et al. Age-related changes in human ciliary muscle and lens: a magnetic resonance imaging study. Invest Ophthalmol Vis Sci. 1999;40:1162–1169.PubMedGoogle Scholar
  49. 50.
    Levy NS. Age-related changes in human ciliary muscle and lens: a magnetic resonance imaging study [letter] Invest Ophthalmol Vis Sci [online]. 2000. Available at: http://www.iovs.org/cgi/eletters/ 40/6/1162#ELO3.Google Scholar
  50. 51.
    Strenk SA, Krishnan A, Semmlow, Strenk LS, DeMarco JK. Volume changes in the in vivo associated with accommodation [abstract]. Invest Ophthalmol Vis Sci. 2001;42:S9.Google Scholar
  51. 52.
    Tripathi RC, Tripathi BJ. Anatomy, orbit and adnexa of the human eye. In: Davson H, ed. The Eye. Vol 1A. 3rd ed. Orlando, Fla: Academic Press; 1984:56–57.Google Scholar
  52. 53.
    Rafferty NS. Structure, function and pathology. In: Maisel H, ed. The Ocular Lens. New York, NY: Marcel Dekker: 1985:2–5.Google Scholar
  53. 54.
    Sakabe I, Oshika T, Lim SJ, Apple DJ. Anterior shift of zonular insertion onto the anterior surface of human crystalline lens with age. Ophthalmology. 1998;105:295–299.PubMedCrossRefGoogle Scholar
  54. 55.
    Lim SJ, Shin JK, Kim HB, Kurata Y, Sakabe I, Apple DJ. Analysis of zonular-free zone and lens size in relation to axial length of eye with age. J Cataract Refract Surg. 1998;24:390–396.PubMedGoogle Scholar
  55. 56.
    Coulombe JL, Coulombe AJ. Lens development. IV. Size. shape and orientation. Invest Ophthalmol. 1969;8:251–257.Google Scholar
  56. 57.
    Marshall J, Bauconsfield M, Rothery S. The anatomy and development of the human lens and zonules. Trans Ophthalmol Soc UK. 1982;102:423–440.PubMedGoogle Scholar
  57. 58.
    Kleinman NJ, Worgul BV. The lens. In: Tasman W, ed. Duane's Foundations of Clinical Ophthalmology. Vol 1. Philadelphia, Pa: JB Lippincott; 1994: chap 15.Google Scholar
  58. 59.
    Duke-Elder S, Waybar KC. Anatomy of the visual system. In: Duke-Elder S, ed. System of Ophthalmology, Vol. 2. London, England: Henry Kimpton; 1962:312–313.Google Scholar
  59. 60.
    Schachar RA, Black TD, Huang T. Understanding Radial Keratotomy. Denison, Tex: LAL Publishing; 1981:100–102.Google Scholar

Copyright information

© Humana Press Inc. 2001

Authors and Affiliations

  1. 1.Presby Corp.Dallas
  2. 2.DRD Technology Corp.TulsaOkla

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