LOGIN TO YOUR ACCOUNT

Username
Password
Remember Me
Or use your Academic/Social account:

CREATE AN ACCOUNT

Or use your Academic/Social account:

Congratulations!

You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.

Important!

Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message

CREATE AN ACCOUNT

Name:
Username:
Password:
Verify Password:
E-mail:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Publisher: Association for Research in Vision and Ophthalmology
Languages: English
Types: Article
Subjects: RE
Purpose. The area of complete spatial summation (Ricco's area) is the largest stimulus size for which area × intensity is constant at threshold. The authors sought to investigate whether Ricco's area changes in early glaucoma to account for the decreased visual signal/noise ratio that may accompany retinal ganglion cell loss.\ud \ud Methods. Spatial summation functions were measured, and Ricco's area was determined at four 10° retinal locations in 24 patients with early glaucoma (total deviation at test locations, mean, −1.3 dB; range, +2 dB to −8 dB) and 26 age-similar healthy subjects under achromatic and S-cone isolation conditions. Achromatic grating resolution acuity was measured at the same locations to estimate functional ganglion cell density.\ud \ud Results. Ricco's area was enlarged in patients compared with controls for both achromatic (enlarged by: superior field, 0.57 log units, P < 0.01; inferior field, 0.72 log units, P < 0.01) and chromatic (enlarged by: superior field, 0.26 log units, P < 0.01; inferior field, 0.25 log units, P = 0.065) stimuli, with negligible vertical summation curve shifts along the intensity axis. Resolution acuity was significantly reduced in glaucoma patients in both hemifields (P < 0.001). There was a weak, but significant, relationship between Ricco's area and resolution acuity.\ud \ud Conclusions. Enlargement of Ricco's area completely compensates for reduced perimetric sensitivity in early glaucoma to maintain constant threshold at Ricco's area, suggesting an increase in signal pooling in response to ganglion cell loss. The rightward displacement of the spatial summation curve indicates that perimetric stimuli should be capable of modulating in size as well as/instead of contrast, which may boost the glaucoma signal within measurement noise.
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • 1. Quigley HA, Addicks EM, Green WR. Optic nerve damage in human glaucoma, III: quantitative correlation of nerve fiber loss and visual field defect in glaucoma, ischemic neuropathy, papilledema, and toxic neuropathy. Arch Ophthalmol. 1982;100:135- 146.
    • 2. Quigley HA, Sanchez RM, Dunkelberger GR, L'Hernault NL, Baginski TA. Chronic glaucoma selectively damages large optic nerve fibers. Invest Ophthalmol Vis Sci. 1987;28:913-920.
    • 3. Quigley HA, Dunkelberger GR, Green WR. Retinal ganglion cell atrophy correlated with automated perimetry in human eyes with glaucoma. Am J Ophthalmol. 1989;107:453- 464.
    • 4. Harwerth RS, Carter-Dawson L, Shen F, Smith EL 3rd, Crawford ML. Ganglion cell losses underlying visual field defects from experimental glaucoma. Invest Ophthalmol Vis Sci. 1999;40:2242- 2250.
    • 5. Kerrigan-Baumrind LA, Quigley HA, Pease ME, Kerrigan DF, Mitchell RS. Number of ganglion cells in glaucoma eyes compared with threshold visual field tests in the same persons. Invest Ophthalmol Vis Sci. 2000;41:741-748.
    • 6. Harwerth RS, Vilupuru AS, Rangaswamy NV, Smith EL 3rd. The relationship between nerve fiber layer and perimetry measurements. Invest Ophthalmol Vis Sci. 2007;48:763-773.
    • 7. Schuman JS, Hee MR, Puliafito CA, et al. Quantification of nerve fiber layer thickness in normal and glaucomatous eyes using optical coherence tomography. Arch Ophthalmol. 1995;113:586 -596.
    • 8. Caprioli J. Early diagnosis of functional damage in patients with glaucoma. Arch Ophthalmol. 1997;115:113-114.
    • 9. Bowd C, Weinreb RN, Williams JM, Zangwill LM. The retinal nerve fiber layer thickness in ocular hypertensive, normal, and glaucomatous eyes with optical coherence tomography. Arch Ophthalmol. 2000;118:22-26.
    • 10. El Beltagi TA, Bowd C, Boden C, et al. Retinal nerve fiber layer thickness measured with optical coherence tomography is related to visual function in glaucomatous eyes. Ophthalmology. 2003; 110:2185-2191.
    • 11. Kanamori A, Nakamura M, Escano MF, Seya R, Maeda H, Negi A. Evaluation of the glaucomatous damage on retinal nerve fiber layer thickness measured by optical coherence tomography. Am J Ophthalmol. 2003;135:513-520.
    • 12. Bowd C, Zangwill LM, Medeiros FA, et al. Structure-function relationships using confocal scanning laser ophthalmoscopy, optical coherence tomography, and scanning laser polarimetry. Invest Ophthalmol Vis Sci. 2006;47:2889 -2895.
    • 13. Hood DC, Kardon RH. A framework for comparing structural and functional measures of glaucomatous damage. Prog Retin Eye Res. 2007;26:688 -710.
    • 14. Quigley HA, Dunkelberger GR, Green WR. Chronic human glaucoma causing selectively greater loss of large optic nerve fibers. Ophthalmology. 1988;95:357-363.
    • 15. Garway-Heath DF, Caprioli J, Fitzke FW, Hitchings RA. Scaling the hill of vision: the physiological relationship between light sensitivity and ganglion cell numbers. Invest Ophthalmol Vis Sci. 2000; 41:1774 -1782.
    • 16. Garway-Heath DF, Holder GE, Fitzke FW, Hitchings RA. Relationship between electrophysiological, psychophysical, and anatomical measurements in glaucoma. Invest Ophthalmol Vis Sci. 2002; 43:2213-2220.
    • 17. Schlottmann PG, De Cilla S, Greenfield DS, Caprioli J, GarwayHeath DF. Relationship between visual field sensitivity and retinal nerve fiber layer thickness as measured by scanning laser polarimetry. Invest Ophthalmol Vis Sci. 2004;45:1823-1829.
    • 18. Harwerth RS, Quigley HA. Visual field defects and retinal ganglion cell losses in patients with glaucoma. Arch Ophthalmol. 2006;124: 853- 859.
    • 19. Malik R, Swanson WH, Garway-Heath DF. Development and evaluation of a linear staircase strategy for the measurement of perimetric sensitivity. Vision Res. 2006;46:2956 -2967.
    • 20. Swanson WH, Felius J, Pan F. Perimetric defects and ganglion cell damage: interpreting linear relations using a two-stage neural model. Invest Ophthalmol Vis Sci. 2004;45:466 - 472.
    • 21. Anderson RS. The psychophysics of glaucoma: improving the structure/function relationship. Prog Retin Eye Res. 2006;25: 79 -97.
    • 22. Pan F, Swanson WH. A cortical pooling model of spatial summation for perimetric stimuli. J Vis. 2006;6:1159 -1171.
    • 23. Wilson ME. Invariant features of spatial summation with changing locus in the visual field. J Physiol. 1970;207:611- 622.
    • 24. Volbrecht VJ, Shrago EE, Schefrin BE, Werner JS. Spatial summation in human cone mechanisms from 0 degrees to 20 degrees in the superior retina. J Opt Soc Am A Opt Image Sci Vis. 2000;17: 641- 650.
    • 25. Vassilev A, Ivanov I, Zlatkova MB, Anderson RS. Human S-cone vision: relationship between perceptive field and ganglion cell dendritic field. J Vision. 2005;5:823- 833.
    • 26. Brindley GS. The summation areas of human colour-receptive mechanisms at increment threshold. J Physiol. 1954;124:400 - 408.
    • 27. Barlow HB. Temporal and spatial summation in human vision at different background intensities. J Physiol. 1958;141:337-350.
    • 28. Glezer VD. The receptive fields of the retina. Vision Res. 1965;5: 497-525.
    • 29. Brindley GS. Physiology of the Retina and Visual Pathway. 2nd ed. London: Edward Arnold; 1970:xi.
    • 30. Davila KD, Geisler WS. The relative contributions of pre-neural and neural factors to areal summation in the fovea. Vision Res. 1991; 31:1369 -1380.
    • 31. Schefrin BE, Bieber ML, McLean R, Werner JS. The area of complete scotopic spatial summation enlarges with age. J Opt Soc Am A Opt Image Sci Vis. 1998;15:340 -348.
    • 32. Dannheim F, Drance SM. Studies of spatial summation of central retinal areas in normal people of all ages. Can J Ophthalmol. 1971;6:311-319.
    • 33. Redmond T, Zlatkova MB, Garway-Heath DF, Anderson RS. The effect of age on the area of complete spatial summation for chromatic and achromatic stimuli. Invest Ophthalmol Vis Sci. 2010;51: 6533- 6539.
    • 34. Fellman RL, Lynn JR, Starita RJ, Swanson WH. Clinical importance of spatial summation in glaucoma. In: Heijl A, ed. Perimetry Update 1988/1989. Amsterdam: Kugler and Gedini: 1989:313- 324.
    • 35. Dannheim F, Drance SM. Psychovisual disturbances in glaucoma: a study of temporal and spatial summation. Arch Ophthalmol. 1974; 91:463- 468.
    • 36. Felius J, Swanson WH, Fellman RL, Lynn JR, Starita RJ. Spatial summation for selected ganglion cell mosaics in patients with glaucoma. In: Wall M, Heijl A, eds. Perimetry Update 1996/1997 Proceedings of the XIIth International Perimetric Society Meeting. Amsterdam: Kugler: 1997:213-221.
    • 37. Battista J, Badcock DR, McKendrick AM. Spatial summation properties for magnocellular and parvocellular pathways in glaucoma. Invest Ophthalmol Vis Sci. 2009;50:1221-1226.
    • 38. Thibos LN, Cheney FE, Walsh DJ. Retinal limits to the detection and resolution of gratings. J Opt Soc Am A. 1987;4:1524 -1529.
    • 39. Anderson RS, Zlatkova MB, Demirel S. What limits detection and resolution of short-wavelength sinusoidal gratings across the retina? Vision Res. 2002;42:981-990.
    • 40. Pentland A. Maximum likelihood estimation: the best PEST. Percept Psychophys. 1980;28:377-379.
    • 41. Seber GAF, Wild CJ. Nonlinear Regression. New York: John Wiley & Sons; 1989.
    • 42. Latham K, Whitaker D, Wild JM, Elliott DB. Magnification perimetry. Invest Ophthalmol Vis Sci. 1993;34:1691-1701.
    • 43. Dalimier E, Dainty C. Role of ocular aberrations in photopic spatial summation in the fovea. Opt Lett. 2010;35:589 -591.
    • 44. Marc RE, Jones BW, Watt CB, Strettoi E. Neural remodeling in retinal degeneration. Prog Retin Eye Res. 2003;22:607- 655.
    • 45. Jones BW, Watt CB, Marc RE. Retinal remodelling. Clin Exp Optom. 2005;88:282-291.
    • 46. Ahmed FA, Chaudhary P, Sharma SC. Effects of increased intraocular pressure on rat retinal ganglion cells. Int J Dev Neurosci. 2001;19:209 -218.
    • 47. Jakobs TC, Libby RT, Ben Y, John SW, Masland RH. Retinal ganglion cell degeneration is topological but not cell type specific in DBA/2J mice. J Cell Biol. 2005;171:313-325.
    • 48. Morgan JE, Datta AV, Erichsen JT, Albon J, Boulton ME. Retinal ganglion cell remodelling in experimental glaucoma. Adv Exp Med Biol. 2006;572:397- 402.
    • 49. Morgan JE. Retinal ganglion cell shrinkage in glaucoma. J Glaucoma. 2002;11:365-370.
    • 50. Peichl L, W¨assle H. The structural correlate of the receptive field centre of alpha ganglion cells in the cat retina. J Physiol. 1983; 341:309 -324.
    • 51. Pan F, Swanson WH, Dul MW. Evaluation of a two-stage neural model of glaucomatous defect: an approach to reduce test-retest variability. Optom Vis Sci. 2006;83:499 -511.
    • 52. Gilbert CD, Wiesel TN. Receptive field dynamics in adult primary visual cortex. Nature. 1992;356:150 -152.
    • 53. King WM, Sarup V, Sauve Y, Moreland CM, Carpenter DO, Sharma SC. Expansion of visual receptive fields in experimental glaucoma. Vis Neurosci. 2006;23:137-142.
    • 54. Artes PH, Iwase A, Ohno Y, Kitazawa Y, Chauhan BC. Properties of perimetric threshold estimates from Full Threshold, SITA Standard, and SITA Fast strategies. Invest Ophthalmol Vis Sci. 2002;43: 2654 -2659.
    • 55. Artes PH, Hutchison DM, Nicolela MT, LeBlanc RP, Chauhan BC. Threshold and variability properties of matrix frequency-doubling technology and standard automated perimetry in glaucoma. Invest Ophthalmol Vis Sci. 2005;46:2451-2457.
    • 56. Wall M, Woodward KR, Doyle CK, Artes PH. Repeatability of automated perimetry: a comparison between standard automated perimetry with stimulus size III and V, matrix, and motion perimetry. Invest Ophthalmol Vis Sci. 2009;50:974 - 979.
  • No related research data.
  • No similar publications.

Share - Bookmark

Cite this article