Advertisement

Intraocular Retinal Prostheses and Related Signal Processing

  • Dean Scribner
  • Eyal Margalit
  • Kah-Guan Au Eong
  • James Weiland
  • E. de JuanJr.
  • Mark S. Humayun
Part of the Topics in Biomedical Engineering International Book Series book series (TOBE)

Abstract

For millennia, restoring sight to the blind has been viewed as being nothing less than miraculous. It has only been in the last few years that the fields of electronic microfabrication, neurophysiology, and retinal surgery have advanced to the point where an implantable visual prosthesis system, based on electrical stimulation, is considered feasible.

Keywords

Electrical Stimulation Ganglion Cell Retinitis Pigmentosa Electrode Array Bipolar Cell 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Agnew, W. F. and McCreery, D. B. (eds), 1990, Neural Prosthesis,Prentice-Hall, New York.Google Scholar
  2. Bak, M., Girvin, J. P., Hambrecht, F. T., et al., 1990, Visual sensations produced by intracortical microstimulation of the human occipital cortex, Med. Biol. Eng. Comput. 28: 257–259.CrossRefGoogle Scholar
  3. Beaudot, W., 1996, Adaptive spatiotemporal filtering by a neuromorphic model of the vertebrate retina, Proc. IEEE Int. Conf. Image, Vol. 1, pp. 427–430.CrossRefGoogle Scholar
  4. Beebe, X. and Rose, T. L., 1988, Charge injection limits of activated iridium oxide electrodes with 0.2 ms pulses in bicarbonate buffered saline, IEEE Trans. Biomed. Eng. 135: 494495.Google Scholar
  5. BeMent, S. L., Wise, K. D., Anderson, D. J., et al., 1986, Solid-state electrodes for multichannel multiplexed intracortical neuronal recording, IEEE Trans. Biomed. Eng. 33: 230–241.CrossRefGoogle Scholar
  6. Bostock, H., 1983, The strength-duration relationship for excitation of myelinated nerve: computed dependence on membrane parameters, J. Physiol. (London). 341: 59–74.Google Scholar
  7. Brabyn, J. A., 1982, New developments in mobility and orientation aids for the blind, IEEE Trans. Biomed. Eng. 29: 285–289.CrossRefGoogle Scholar
  8. Brindley, G. S. and Lewin, W. S., 1968a, The sensations produced by electrical stimulation of the visual cortex, J. Physiol. (London). 196: 479–493.Google Scholar
  9. Brindley, G. S. and Lewin, W. S., 1968b, The visual sensations produced by electrical stimulation of the medial occipital cortex, J Physiol. (London). 194: 54–55 P.Google Scholar
  10. Brindley, G. S., 1965, The number of information channels needed for efficient reading, J. Physiol. 177: 44 P.Google Scholar
  11. Brown, W. J., Babb, T. L., Soper, H.V., et al., 1977, Tissue reactions to long-term electrical stimulation of the cerebellum in monkeys, J. Neurosurg. 47: 366–379.CrossRefGoogle Scholar
  12. Brummer, S. B. and Turner, M. J., 1975, Electrical stimulation of the nervous system: The principle of safe charge injection with noble metal electrodes, Bioelectrochem. Bioenerg. 2: 13–25.CrossRefGoogle Scholar
  13. Bullara, L. A., McCreery, D. B., Yuen, T. G., and Agnew, W. F., 1983, A microelectrode for delivery of defined charge densities, J. Neurosci. Methods. 9: 15–21.CrossRefGoogle Scholar
  14. Cha, K., Horch, K. W., and Norrnann, R. A., 1992a, Mobility performance with a pixelized vision system, Vision Res. 32: 1367–1372.CrossRefGoogle Scholar
  15. Cha, K., Horch, K. W., Norman, R. A., Boman, D. K., 1992b, Reading speed with a pixelized vision system, J. Opt. Soc. Am. 9: 673–677.CrossRefGoogle Scholar
  16. Cha, K., Horch, K., Norman, R. A., 1992c, Simulation of a phosphene-based visual field: visual acuity in a pixelized vision system, Ann. Biomed. Eng. 20: 439–449.CrossRefGoogle Scholar
  17. Chen, S. J., Humayun, M. S, Weiland, J. D., et al., 2000, Electrical stimulation of the mouse retina: A study of electrically elicited visual cortical responses, Invest. Ophthal. Vis. Sci. 40: S889.Google Scholar
  18. Chow, A. Y. and Chow, V. Y., 19997, Subretinal electrical stimulation of the rabbit retina, Neurosci. Lett. 225: 13–16.Google Scholar
  19. Chow, A. Y. and Peachey, N. S., 1998, The subretinal microphotodiode array retinal prosthesis [letter; comment], Ophthalmic Res. 30: 195–198.CrossRefGoogle Scholar
  20. Cole, J. and Curtis, H., 1939, Electric impedance of the squid giant axon during activity, J. Gen. Physiol. 22: 649–670.CrossRefGoogle Scholar
  21. Curlander, J. C. and Marmarrelis, V. Z., 1983, Processing of visual information in the distal neurons of the vertebra retina, IEEE, 13: 934–943.zbMATHGoogle Scholar
  22. Dacey, D. M., 1996, Circuitry for color coding in the primate retina, Proc. Nat. Acad. Sci., 93: 582–588.CrossRefGoogle Scholar
  23. de Juan, E., Humayun, M. S., Hatchell, D., and Wilson, D., 1989, Histopathology of experimental retinal neovascularization, Invest. Ophthal. Vis. Sci. 30: 1495.Google Scholar
  24. Delbruck, T. and Mead, C.A., 1994, Adaptive photoreceptor with wide dynamic range, Proc. IEEE Int. Symp. on Circuits and Systems, ISCAS ‘84, Vol. 4, pp. 339–342.Google Scholar
  25. Djourno, A. and Eyries, C., 1957, Prothese auditive par excitation electrique a distance du nerf sensorial a l’aide d’un bobinage inclus a demeure, Presse Med. 35: 14–17.Google Scholar
  26. Dobelle, W. H. and Mladejovsky, M. G., 1974, Phosphenes produced by electrical stimulation of human occipital cortex, and their application to the development of a prosthesis for the blind, J. PhysioL (London). 243: 553–576.Google Scholar
  27. Dobelle, W. H., 1994, Artificial vision for the blind. The summit may be closer than you think, ASAIO J. 40: 919–922.Google Scholar
  28. Dobelle, W. H., Mladejovsky, M.G, Evans J. R., et al., 1976, “Braille” reading by a blind volunteer by visual cortex stimulation, Nature. 259: 111–112.Google Scholar
  29. Dowling, J. E., 1987, The Retina: An Approachable Part of the Brain, Belknap Press, Cambridge.Google Scholar
  30. Eckmiller, R., 1997, Learning retina implants with epiretinal contacts, Ophthalmic Res. 29: 281–289.CrossRefGoogle Scholar
  31. Foerster, O., 1929, Beitrage zur pathophysiologie der sehbahn und der spehsphare, J. Psycho!. Neurol. (Lpz). 39: 435–463.Google Scholar
  32. Fritsch, G. and Hitzig J., 1870, Ueber die elecktrische erregbarkeit des grosshims. Arch. Anat. Physiol. 37: 300–332.Google Scholar
  33. Galvani L., 1791, De viribus electricitatis in motu musculary, commentarius. De Bononiensi Scientiarum et Artium Institute atque Academia. 7: 363–418.Google Scholar
  34. Glenn,W., Mauro, E., Longo, P., et al., 1959, Remote stimulation of the heart by radio frequency transmission, New Eng. J. Med. 261: 948.CrossRefGoogle Scholar
  35. Gorman, P. H. and Mortimer, J. T., 1983, The effect of stimulus parameters on the recruitment characteristics of direct nerve stimulation, IEEE Trans. Biomed. Eng. 30: 407–414.CrossRefGoogle Scholar
  36. Greenberg, R. J., 1998, Analysis of Electrical Stimulation of the Vertebrate Retina—Work Towards a Retinal Prosthesis, Ph.D. Dissertation, The Johns Hopkins University, Baltimore, MD.Google Scholar
  37. Greenberg, R. J., Velte, T.J., Humayun, M. S., et al., 1999, A computational model of electrical stimulation of the retinal ganglion cell, IEEE Trans. Biomed. Eng. 46: 505–514.CrossRefGoogle Scholar
  38. Grumet, A. E., Rizzo, J. F., and Wyatt, J. L., 1999, Ten Micron Diameter Electrodes Directly Stimulate Rabbit Retinal Ganglion Cell Axons, Invest. Ophthal. Vis. Sci. 40: S734.Google Scholar
  39. Grumet, A. E., Rizzo, J. F., and Wyatt, J., 2000, In-vitro electrical stimulation of human retinal ganglion cell axons, Invest. Ophthal. Vis. Sci. 41: S10.Google Scholar
  40. Guenther, E., Trager, B., Schlosshauer, B., and Zrenner, E., 1999, Long-term survival of retinal cell cultures on retinal implant materials, Vision Res. 39: 3988–3994.CrossRefGoogle Scholar
  41. Heetderks, W. J., 1988, RF powering of millimeter and submillimeter sized neural prosthetic implants, IEEE Trans. Biomed. Eng. 35: 323–326.CrossRefGoogle Scholar
  42. Heiduschka, P. and Thanos, S., 1998, Implantable bioelectronic interfaces for lost nerve functions, Prog. Neurobiol. 55: 433.CrossRefGoogle Scholar
  43. Hetke, J. F., Lund, J. L., Najafi, K., et al., 1994, Silicon ribbon cables for chronically implantable microelectrode arrays, IEEE Trans. Biomed. Eng. 41: 314–321.CrossRefGoogle Scholar
  44. Hodgkin, A. and Huxley, A., 1952a, Currents carried by sodium and potassium ions through the membrane of the giant axon of loligo, J. Physiol. 116: 472–49.Google Scholar
  45. Hodgkin, A. and Huxley, A., 1952b, A quantitative description of membrane current and its application to conduction and excitation in nerve, J. Physiol. 116: 500–544.Google Scholar
  46. Humayun, M., 1994, Is Surface Electrical Stimulation of the Retina a Feasible Approach Towards the Development of a Visual Prosthesis? Ph.D. Dissertation, Johns Hopkins University School of Medicine, Baltimore, MD.Google Scholar
  47. Humayun, M., de Juan, E., Jr., Dagnelie,G., Greenberg, R, Propst, R., and Phillips, H., 1996, Visual perception elicited by electrical stimulation of retina in blind humans, Arch. Ophthalmol. 114: 40–46.Google Scholar
  48. Humayun, M. S., de Juan, E. J, Weiland, J.D., et al., 1999, Pattern electrical stimulation of the human retina, Vision Res. 39: 2569–2576.CrossRefGoogle Scholar
  49. Humayun, M. S., de Juan, E. J., Dagnelie, G., et al., 1996, Visual perception elicited by electrical stimulation of retina in blind humans, Arch. Ophthalmol. 114: 40–46.CrossRefGoogle Scholar
  50. Humayun, M. S., Prince, M., de Juan, E. J., et al., 1999, Morphometric analysis of the extramacular retina from postmortem eyes with retinas pigmentosa, Invest. Ophthal. Vis. Sci. 40: 143–148.Google Scholar
  51. Humayun, M. S., Propst, R., de Juan, E. J., et al., 1994, Bipolar surface electrical stimulation of the vertebrate retina, Arch. Ophthalmol. 112: 110–116.CrossRefGoogle Scholar
  52. Janders, M., Egert, U., Stelze, M., and Nisch, W., 1996, Novel thin-film titanium nitride micro-electrodes with excellent charge transfer capability for cell stimulation and sensing applications, Proc. 19th Int. Conf IEEEJEMBS, pp. 1191–1193.Google Scholar
  53. Jones, K. E. and Normann, R. A., 1997, An advanced demultiplexing system for physiological stimulation, IEEE Trans. Biomed. Eng. 44: 1210–1220.CrossRefGoogle Scholar
  54. Kamy, H., 1975, Clinical and physiological aspects of the cortical visual prosthesis, Surv. Ophthalmol. 20: 47–58.CrossRefGoogle Scholar
  55. Knighton, R. W., 1975a, An electrically evoked slow potential of the frog’s retina. I. Properties of response, J. Neurophysiol. 38: 185–197.Google Scholar
  56. Knighton, R. W., 1975b, An electrically evoked slow potential of the frog’s retina. II. Identification with PII component of electroretinogram, J. Neurophysiol. 38: 198–209.Google Scholar
  57. Kolb, H., Fernandez, E., and R. Nelson, Web Visionan internet resource, located at http://webvision.med.utah.eduGoogle Scholar
  58. Kolb, H., Linberg, K. A., and Fisher, S. K., 1992, The neurons of the human retina: a Glogi study, J. Comp. Neurol. 318: 147–187.CrossRefGoogle Scholar
  59. Kovacs, G. T., Storment, C. W., Rosen, J. M., 1992, Regeneration microelectrode array for peripheral nerve recording and stimulation, IEEE Trans. Blamed. Eng. 39: 893–902.CrossRefGoogle Scholar
  60. Krause, F. and Schum, H., 1931, Die epiliptischen erkankungen, in: Neue Deutsche Shirurgie, H. Kunter, ed., Stuttgart, Chap. 49a, pp 482–486.Google Scholar
  61. Laing, P. G., Ferguson, A. B., Jr., and Hodge, E. S., 1967, Tissue reaction in rabbit muscle exposed to metallic implants, J. Blamed. Mater. Res. 1: 135–149.CrossRefGoogle Scholar
  62. Lilly, J. C., 1961, Injury and excitation by electric currents: The balanced pulse-pair waveform, in: Electrical Stimulation of the Brain, D. E. Sheer, ed., Hogg Foundation for Mental Health, pp. 60–64.Google Scholar
  63. Liu W, Vichienchom K, Clements M, Demarco C, Hughes C, McGucken E, Humayun MS, de Juan E. Jr., Weiland J. D., 2000, A neuro-stimulus chip with telemetry unit for retinal prosthesis device. IEEE Solid-State Circuits. 35: 1487–1497.CrossRefGoogle Scholar
  64. Majji, A. B, Humayun, M. S, Weiland, J. D., et al., 1999, Long-term histological and electrophysiological results of an inactive epiretinal electrode array implantation in dog, Invest. Ophthal. Vis. Sci. 40: 2073–2081.Google Scholar
  65. Margalit„ E., Fujii, G., Lai J, et al., 2000, Bioadhesives for intraocular use, Retina, 20: 469–477.Google Scholar
  66. Maynard, E. M., Nordhausen, C. T., and Normann, R. A., 1997, The Utah intra.cortical electrode array: a recording structure for potential brain-computer interfaces, Electroencephalogr. Clin. Neurophysiol. 102: 228–239.CrossRefGoogle Scholar
  67. McCreery, D. B., Agnew, W. F., Yuen, T. G., and Bullara, L. A., 1988, Comparison of neural damage induced by electrical stimulation with faradaic and capacitor electrodes, Ann. Biomed. Eng. 16: 463–481.CrossRefGoogle Scholar
  68. McCreery, D. B., Agnew, W. F., Yuen, T. G.H., and Bullara, L., 1990, Charge density and charge per phase as cofactors in neural injury induced by electrical stimulation, IEEE Trans. Biomed. Eng. 37: 996–1001.CrossRefGoogle Scholar
  69. McHardy, J., Robblee, L. S., Marston, J. M., and Brummer, S. B., 1980, Electrical stimulation with pt electrodes. IV. Factors influencing Pt dissolution in inorganic saline, Biomater. 1: 129–134.CrossRefGoogle Scholar
  70. Nordhausen, C. T., Maynard, E. M., and Nomiatm, R. A.., 1996, Single unit recording capabilities of a 100 microelectrode array, Brain Res. 726: 129–140.CrossRefGoogle Scholar
  71. Nomiann, R. A., 1999, MERPWD. A neural interface for a cortical vision prothesis, Vision Res. 39: 2577–2587.CrossRefGoogle Scholar
  72. Osterberg, G. (1935) Topography of the layer of rods and cones in the human retina, Acta Ophthal. supp. 6: 1–103.Google Scholar
  73. Ogden, T.E. (1989) Retina: Basic Science and Inherited Retinal Disease, Vol I. The CV Mosby Co., St. Louis.Google Scholar
  74. Penfield, W. and Jasper, H., 1954, Epilepsy and the Functional Anatomy of the Human Brain, Churchill, London.Google Scholar
  75. Penfield, W. and Rasussen, T., 1952, The Cerebral Cortex of Man, Macmillan, New York, pp. 135–147.Google Scholar
  76. Peyman, G., Chow, A. Y, Liang, C., et al., 1998, Subretinal semiconductor microphotodiode array, Ophthalmic Surg. Lasers. 29: 234–241.Google Scholar
  77. Pollen, D. A., 1977, Responses of single neurons to electrical stimulation of the surface of the visual cortex, Brain Behay. Evol. 14: 67–86.CrossRefGoogle Scholar
  78. Polyak, S.L. (1941) The Retina. University of Chicago Press, Chicago.Google Scholar
  79. Potts, A. M. and Inoue J., 1970, The electrically evoked response of the visual system (EER) III. Further consideration to the origin of the EER, Invest. Ophthal Vis. Sci.. 9: 814–819.Google Scholar
  80. Potts, A. M. and Inoue, J., 1969, The electrically evoked response (EER) of the visual system II. Effect of adaptation and retinitis pigmentosa, Invest. Ophthal. Vis. Sci. 8: 605–612.Google Scholar
  81. Potts, A. M., Inoue, J., and Buffum, D., 1968, The electrically evoked response of the visual system (EER), Invest. Ophthal. Vis. Sci. 7: 269–278.Google Scholar
  82. Pudenz, R. H., Bullara, L. A., Dru, D., and Talalla, A., 1975a, Electrical stimulation of the brain. II. Effects on the blood-brain barrier, Surg. Neural. 4: 265–270.Google Scholar
  83. Pudenz, R. H., Bullara, L. A., Jacques, S., and Hambrecht, F. T., 1975b, Electrical stimulation of the brain. III. The neural damage model, Surg. Neural. 4: 389–400.Google Scholar
  84. Pudenz, R.H., Bullara, L.A., and Talalla, A., 1975c, Electrical stimulation of the brain. I. Electrodes and electrode arrays, Surg. Neurol. 4: 37–42.Google Scholar
  85. Rita, P., Kaczmarek, K A, Tyler, M. E., and Garcia-Lara, J., 1998, Form perception with a 49- point electrotactile stimulus array on the tongue: a technical note, J. Rehabil. Res. Dev. 35: 427–430.Google Scholar
  86. Rizzo, J. and Wyatt, J., 1997, Prospects for a visual prosthesis, Neuroscientist, 3: 251–262.CrossRefGoogle Scholar
  87. Rizzo, J., Wyatt, J., Loewenstein, J., and Kelly, S., 2000, Acute intraocular retinal stimulation in normal and blind humans, Invest. Ophthal. Vis. Sci. 41: S102.Google Scholar
  88. Robblee, L. S., Mangaudis, M., Lasinski, E., et al., 1986, Charge injection properties of thermally-prepared iridium oxide films, Mat. Res. Soc. Symp. Proc. 55: 303–310.CrossRefGoogle Scholar
  89. Santos, A., Humayun, M. S., de Juan, E. J., et al., 1997, Preservation of the inner retina in retinitis pigmentosa. A morphometric analysis, Arch. Ophthalmol. 115: 511–515.CrossRefGoogle Scholar
  90. Sato, S., Sugimoto, S., and Chiba, S., 1982, A procedure for recording electroretinogram and visual evoked potential in conscious dog, J. Pharmacol. Methods. 8: 173–181.CrossRefGoogle Scholar
  91. Schmidt, E. M, Bak, M. J, Hambrecht, F. T, et al., 1996, Feasibility of a visual prosthesis for the blind based on intracortical microstimulation of the visual cortex, Brain. 119 (Pt 2): 507–522.CrossRefGoogle Scholar
  92. Schmidt, E. M, Bak, M. J., and Christensen, P., 1995, Laser exposure of Parylene-C insulated microelectrodes, J. Neurosci. Methods 62: 89–92.CrossRefGoogle Scholar
  93. Schwarz, M. et al., 1999, Single-chip CMOS image sensors for a retina implant system, IEEE Trans. Circuits Syst.-II: Analog Dig. Signal Proc. 46: 870–877.CrossRefGoogle Scholar
  94. Scribner, D. A., Kruer, M. R., and Killiany, J. M., 1991, Infrared focal plane array technology, Proc. IEEE. 79: 65–85.Google Scholar
  95. Shapley, R. and Enroth-Cugell, C., 1984, Visual adaptation and retina gain controls, in Progress in Retinal Research, Vol. 3, N. N. Osborne and G. J. Chader, eds., Pergamon, New York.Google Scholar
  96. Shyu, J., Maia, M., Weiland, J., et al., 2000, Electrical Stimulation of Isolated Rabbit Retina, Biomedical Engineering Society Annual Meeting, Seattle, WA. 28: S115.Google Scholar
  97. Sterling, T. D. and Vaughn, H. G., Jr., 1971, Feasibility of electrocortical prosthesis, in: Visual Prosthesis: The Interdisciplinary Dialogue, T.D. Sterling et al., ed., Academic Press, New York.Google Scholar
  98. Stone, J. L., Barlow, W. E., Humayun, M. S., et al., 1992, Morphometric analysis of macular photoreceptors and ganglion cells in retinas with retinitis pigmentosa, Arch. Ophthalmol. 110: 1634–1639.CrossRefGoogle Scholar
  99. Suzuki, S., Humayun, M., de Juan, E., et al., 1999, A comparison of electrical stimulation threshold in normal mouse retina vs. different aged retinal degenerate (rd) mouse retina, Invest. Ophthal. Vis. Sci. 40: S735.Google Scholar
  100. Teeters, J., Jacobs, A., and Werblin, F., 1997, How neural interactions form neural responses in the Salamander retina, J. Comp. Neurosci. 4: 5.CrossRefGoogle Scholar
  101. Tehovnik, E., 1996, Electrical stimulation of neural tissue to evoke behavioral responses, J. Neurosci. Methods. 65: 1–17.CrossRefGoogle Scholar
  102. Thompson, R, Barnett, D., Humayun, M., and Dagnelie, G., 2000, Reading speed and facial recognition using simulated prosthetic vision, Invest. Ophthal. Vis. Sci. 41: S860.Google Scholar
  103. Tonucci, R.J. and Justus, B.L., 1993a, Nanocchannel Glass Matrix Used in Making Mesoscopic Structures, U.S. Patent 5,264,722, issued November 1993.Google Scholar
  104. Tonucci, R.J. and Justus, B.L., 1993b, Nanochannel Filter, U.S. Patent 5,234,594, issued August 1993.Google Scholar
  105. Tonucci, R. J., Justus, B. L., Campillo, A. J., and Ford, C. E., 1992, Nanochannel array glass, Science. 258: 783–785.CrossRefGoogle Scholar
  106. Toyoda, J. and Fujimoto, M., 1984, Application of transretinal current stimulation for the study of bipolar-amacrine transmission, J. Gen. Physiol. 84: 915–925.CrossRefGoogle Scholar
  107. Troyk, P. and Schwan, M., 1992, Closed-loop class E transcutaneous power and data link for microimplants, IEEE Trans. Biomed. Eng. 39: 589–599.CrossRefGoogle Scholar
  108. Turner, J. N., Shain, W., Szarowski, D. H., et al., 1999, Cerebral astrocyte response to micromachined silicon implants, Exp. Neural. 156: 33–49.CrossRefGoogle Scholar
  109. Veraart, C., Raftopoulos, C., Mortimer, J. T., et al., 1998, Visual sensations produced by optic nerve stimulation using an implanted self-sizing spiral cuff electrode, Brain Res. 813: 181–186.CrossRefGoogle Scholar
  110. Weiland, J. D. and Anderson, D. J., 2000, Chronic neural stimulation with thin-film, iridium oxide stimulating electrodes, IEEE Trans. Biomed. Eng. 47: 911–918.CrossRefGoogle Scholar
  111. Weiland, J. D., Humayun, M. S., Dagnelie, G., et al., 1999, Understanding the origin of visual percepts elicited by electrical stimulation of the human retina, Graefes Arch. Clin. Exp. Ophthalmol. 237: 1007–1013.CrossRefGoogle Scholar
  112. West, D. C. and, Wolstencroft, J. H., 1983, Strength-duration characteristics of myelinated and non-myelinated bulbospinal axons in the cat spinal cord, J. Physiol. (London). 337: 37–50.Google Scholar
  113. Wiley, J. D. and Webster, J. G., 1982, Analysis and control of the current distribution under circular dispersive electrodes, IEEE Trans. Biomed. Eng. 29: 381–385.CrossRefGoogle Scholar
  114. Wise, K. D., Angell, J., and Starr, A., 1970, An integrated-circuit approach to extracellular microelectrodes, IEEE Trans. Biomed. Eng. 17: 238–247.CrossRefGoogle Scholar
  115. Wyatt, J. and Rizzo, J. F., 1996, Ocular implants for the blind, IEEE Spectrum. 112: 47–53.CrossRefGoogle Scholar
  116. Yagi, T. and Hayashida, Y., 1999, Implantation of the artificial retina, Nippon Rinsho. 57: 1208–1215.Google Scholar
  117. Yagi, T. and Watanabe, M. A., 1998, A computational study on an electrode array in a hybrid retinal implant, Proc. of 1998 IEEE Int. Joint Conf on Neural Networks, pp. 780–783.Google Scholar
  118. Zrenner, E., Stett, A., Weiss, S., et al., 1999, Can subretinal microphotodiodes successfully replace degenerated photoreceptors? Vis. Res. 39: 2555–2567.CrossRefGoogle Scholar
  119. Zuidema, P., Koenderink, J. J., and Bouman, M. A., 1983, A mechanistic approach to threshold behavior of the visual system, IEEE Trans. Syst. Man Cybernet. 13: 923.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2002

Authors and Affiliations

  • Dean Scribner
    • 1
  • Eyal Margalit
    • 2
  • Kah-Guan Au Eong
    • 3
  • James Weiland
    • 2
  • E. de JuanJr.
    • 4
  • Mark S. Humayun
    • 4
  1. 1.U.S. Naval Research LaboratoryUSA
  2. 2.Wilmer Eye InstituteJohns Hopkins UniversityBaltimoreUSA
  3. 3.Department of OphthalmologyTan Tock Seng HospitalSingapore
  4. 4.Wilmer Eye InstituteJohns Hopkins UniversityBaltimoreUSA

Personalised recommendations