Advertisement

Abnormal Cone Receptor Activity in Patients with Hereditary Degeneration

  • Donald C. Hood
  • David G. Birch
Chapter

Abstract

Although often thought of as a disease that primarily affects the rods, retinitis pigmentosa (RP) delays the implicit times of the cone ERGs very early in progression (see ref. 1 for review). The first two panels of Figure 1 show the cone responses recorded as part of a standard clinical protocol from a normal subject and four patients with RP. Cone ERGs are recorded by presenting a single white flash on a background that suppresses the rods (left panel) or by presenting a 30 Hz pulse train, too fast for the rods to follow, to the dark adapted eye (right panel). The vertical dashed lines in Fig. 1 mark the peak times for the normal observer and the patients’ records were selected to illustrate a range of implicit times. In general, patients with RP show delays in the peak response to both the single flashes and the 30 Hz flicker. These delays have been attributed, at least in part, to cone photoreceptor abnormalities, specifically to a decrease in quantal absorption by the cone outer segments (1–3). Other ERG evidence is more difficult to reconcile with only a change in quantal absorption (4–10).

Keywords

Retinitis Pigmen Outer Segment Implicit Time Single Flash Cone ERGs 
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. 1.
    Berson, E., 1993, Retinitis pigmentosa: the Friedenwald lecture, Invest. Ophthal. and Vis. Sci, 34:1659–1676.Google Scholar
  2. 2.
    Sandberg, M., Sullivan, P., & Berson, E., 1981, Temporal aspects of the dark-adapted cone a-wave in retinitis pigmentosa, Invest. Ophthal. and Vis. Sci, 21:765–769.Google Scholar
  3. 3.
    Gouras, P., & MacKay, C. J., 1989, Light adaptation of the electroretinogram, Invest. Ophthal. and Vis. Sci, 30:619–624.Google Scholar
  4. 4.
    Berson, E., Gouras, P., & Hoff, M., 1969,. Temporal aspects of the electroretinogram. Arch, of Ophthal., 81:207–214.CrossRefGoogle Scholar
  5. 5.
    Massof, R., Johnson, M., Sunness, J., Perry, C., & Finkelstein, D., 1986, Flicker electroretinogram in retinitis pigmentosa. Doc. Ophthal, 62:231–245.CrossRefGoogle Scholar
  6. 6.
    Seiple, W., Siegel, I., Carr, R., & Mayron, C., 1986, Evaluating macular function using the focal ERG. Invest. Ophthal. and Vis. Sci, 27:1123–1130.Google Scholar
  7. 7.
    Birch, D. G., & Sandberg, M. A., 1987, Dependence of cone b-wave implicit on rod amplitude in retinitis pigmentosa. Vis. Res. 27:1105–1112.PubMedCrossRefGoogle Scholar
  8. 8.
    Seiple, W., Greenstein, V, & Carr, R., 1989, Losses of temporal modulation sensitivity in retinal degenerations. Brit. J. of Ophthal, 73:440–447.CrossRefGoogle Scholar
  9. 9.
    Miller, S., & Sandberg, M., 1991, Cone electroretinographic change during light adaptation in retinitis pigmentosa. Invest. Ophthal. and Vis. Sci, 32:2536–2541.Google Scholar
  10. 10.
    Falsini, B., Iarossi, G., Porciatti, V., Merendino, E., Fadda, A., Cermola, S., and Buzzonetti, L., 1994, Postreceptoral contribution to Macular dysfunction in retinitis pigmentosa. Invest. Ophthal. and Vis. Sci, 35:4282–4290.Google Scholar
  11. 11.
    Birch, D. G., & Anderson, J., 1992, Standardized full-field electroretinography: Normal values and their variation with age. Arch, of Ophthal., 110:1571–1576.CrossRefGoogle Scholar
  12. 12.
    Birch, D. G., & Fish, G. E., 1987, Rod ERGs in retinitis pigmentosa and cone-rod degeneration. Invest. Ophthal. and Vis. Sci, 28:140–150.Google Scholar
  13. 13.
    Hood, D. C., & Birch, D. G., 1993, Human cone receptor activity: The leading edge of the a-wave and models of receptor activity. Vis. Neurosci, 10:857–871.PubMedCrossRefGoogle Scholar
  14. 14.
    Hood, D., & Birch, D., 1995, Phototransduction in human cones measured using the a-wave of the ERG. Vis. Res., In press.Google Scholar
  15. 15.
    Lamb, T. D., & Pugh, E. N., 1992, A quantitative account of the activation steps involved in phototransduction in amphibian photoreceptors. J. of Physiol. 499:719–758.CrossRefGoogle Scholar
  16. 16.
    Hood, D. C., & Birch, D. G., 1994, Rod phototransduction in retinitis pigmentosa: Estimation and interpretation of parameters derived from the rod a-wave. Invest. Ophthal. and Vis. Sci, 35:2948–2961.Google Scholar
  17. 17.
    Breton, M., Schueller, A., Lamb, T., & Pugh, J., EN, 1994, Analysis of ERG a-wave amplification and kinetics in terms of the G-protein cascade of phototransduction. Invest. Ophthal. and Vis. Sci, 35:295–309.Google Scholar
  18. 18.
    Lachapelle, P., Little, J. M., & Polomeno, R. C., 1983, The photopic electroretinogram in congenital stationary night blindness with myopia. Invest. Ophthal. and Vis. Sci, 24:442–450.Google Scholar
  19. 19.
    Peachey, N. S., Alexander, K. R., Derlacki, D. J., Bobak, P., & Fishman, G. A., 1990, Light adaptation, rods, and the human cone flicker ERG. Vis. Neurosci, 8:142–150.Google Scholar
  20. 20.
    Kergoat, H., & Lovasik, J. V, 1990, The effects of altered retinal vascular perfusion pressure on the white flash scotopic ERG and oscillatory potentials in man. Electroencephal and Clin. Neurophysiol., 75:306–322.CrossRefGoogle Scholar
  21. 21.
    Heynen, H., Wachtmeister, L., and van Norren, D., 1985, Origin of the oscillatory potentials in the primate retina. Vis. Res., 25:1365–1373.PubMedCrossRefGoogle Scholar
  22. 22.
    Nusinowitz, S., & Birch, D. G., 1995, The topography of rod and cone sensitivity loss in retinal perimetry.Google Scholar
  23. 23.
    Hood, D.C., Shady, S. Birch, D. G., 1993, Heterogeneity in retinal disease and the computational model of the human rod response. J. Opt. Soc. Amer., 10:1624–1630.CrossRefGoogle Scholar
  24. 24.
    Hood, D. C., Shady, S, & Birch, D. G., 1994, Understanding changes in the b-wave of the ERG caused by heterogeneous receptor damage. Invest. Ophthal. and Vis. Sci, 35:2477–2488.Google Scholar
  25. 25.
    Shady, S., Hood, D. C. & Birch, D. G., 1995, Rod phototransduction in retinitis pigmentosa: Distinguishing alternative mechanisms of degeneration. Invest. Ophthal. and Vis. Sci, In press.Google Scholar

Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Donald C. Hood
    • 1
  • David G. Birch
    • 2
  1. 1.Department of PsychologyColumbia UniversityNew YorkUSA
  2. 2.Retina Foundation of the SouthwestDallasUSA

Personalised recommendations