rss
Br J Ophthalmol 2003;87:1268-1271 doi:10.1136/bjo.87.10.1268
  • Laboratory science - Scientific reports

Interocular amplitude differences of the full field electroretinogram in normal subjects

  1. Y Rotenstreich1,
  2. G A Fishman1,
  3. R J Anderson2,
  4. D G Birch3
  1. 1Department of Ophthalmology and Visual Science, University of Illinois at Chicago, Chicago, IL, USA
  2. 2Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL, USA
  3. 3Retina Foundation of the Southwest, Dallas, TX, USA
  1. Correspondence to: Professor Gerald A Fishman, 1855 W Taylor Chicago, IL 60612, USA; gerafish{at}uic.edu
  • Accepted 21 January 2003

Abstract

Aims: To determine the interocular amplitude response difference of the electroretinogram (ERG) in normal subjects.

Methods: 79 subjects, without retinal changes of clinical significance, underwent ERG testing. They included 63 men and 16 women, with a mean age of 44 (SD 12) years and range of 18–65 years. Isolated rod, scotopic maximal, dark adapted 30 Hz flicker, photopic single flash, and light adapted 30 Hz flicker responses were recorded in both eyes following the International Society for Clinical Electrophysiology of Vision (ISCEV) standard protocol. The interocular percentage differences of the ERG b-wave amplitudes were calculated and presented as percentiles (25th, 50th, 75th, 95th), means (SD), and medians.

Results: The median interocular percentage differences in the b-wave amplitudes for the above ERG stimulus responses were 10%, 8%, 10%, 11%, and 10%, respectively. The mean interocular percentage differences were 11%, 11%, 12%, 13%, and 14%. The 95th percentiles for the interocular percentage differences were 28%, 27%, 36%, 33%, and 35%, respectively.

Conclusions: The interocular percentage differences in the ERG b-wave amplitudes for five different stimulus responses were similar in our cohort of individuals without clinically significant retinal changes and ranged from a median of 8–11% and a 95th percentile of 27–36%. Our findings should be useful for determining sample sizes in future therapeutic trials on retinal diseases with monocular therapeutic strategies and may also have application for the more accurate detection of asymmetric retinal disease.

Footnotes

    Register for free content

    The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.

    Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.