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Micropsia and visual acuity in macular edema

A study of the neuro-retinal basis of visual acuity
  • Lars Frisén
  • Marianne Frisén
Article

Summary

Relative micropsia was measured by a matching technique in patients with unilateral, benign, macular edema. Quantitative assessment of foveolar micropsia appeared to be a sensitive indicator of receptor displacement in this disorder, and may be a useful tool both for diagnosing and for monitoring macular edema.

Parallel measurements of grating acuity showed a close proportionality between acuity and micropsia parameters. This result validates a new quantitative theory for the neuro-retinal basis of visual acuity. The theory allows prediction of the proportion of working visual neurons in patients with impaired acuity due to diseases that produce a diffuse loss, or disconnection, of macular cones. Our results indicate that so-called normal visual acuity (1.0, or 20/20) requires no more than 44% of the normal quantity of foveolar, neuro-retinal channels.

Keywords

Public Health Visual Acuity Quantitative Assessment Normal Quantity Macular Edema 
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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Copyright information

© Springer-Verlag 1979

Authors and Affiliations

  • Lars Frisén
    • 1
  • Marianne Frisén
    • 1
  1. 1.The Departments of Ophthalmology and StatisticsUniversity of GöteborgSweden

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