Electroretinographic alterations in the Laurence-Moon-Bardet-Biedl phenotype.


Journal Article

Maximal 0.5-Hz and cone 30-Hz ERG responses were recorded from 19 patients showing a Laurence-Moon-Bardet-Biedl (LMDD) phenotype. Off-line averaging of 80 to 100 iterations was routinely performed. When needed, our previously described low-noise techniques and off-line fast Fourier transform procedures were used. The maximal ERG response was non-detectable in 52.6% of cases. About half of the recordable signals were below 5% of the lower normal amplitudes. Cone 30-Hz ERGs were measurable in 64.7% of cases. Of these, 63% of tracings were below 5% of the lower normal range. In most cases no dystrophic pattern was definable, due to severe reduction of both signals. Statistical analyses showed no correlation between ERG amplitudes and residual visual field areas. Clinical and electroretinographic observations suggest that retinopathy in most LMBB patients is a widespread form of degeneration, initially affecting rods but rapidly involving cones as well. However, there are also cases with a clear-cut cone-rod pattern, with fairly well preserved maximal ERG responses. The lack of correlation between maximal ERG responses and visual field residual areas, different from non-syndromic retinitis pigmentosa (RP) patients, could be related either to a low reliability of visual field testing in LMBB patients or to mechanisms accounting for the ongoing retinal degeneration in LMBB syndrome that are different from those of pure RP. Variable findings are in line with the documented genetic heterogeneity of the syndrome.

Full Text

Duke Authors

Cited Authors

  • Iannaccone, A; Vingolo, EM; Rispoli, E; De Propris, G; Tanzilli, P; Pannarale, MR

Published Date

  • February 1996

Published In

Volume / Issue

  • 74 / 1

Start / End Page

  • 8 - 13

PubMed ID

  • 8689489

Pubmed Central ID

  • 8689489

International Standard Serial Number (ISSN)

  • 1395-3907

Digital Object Identifier (DOI)

  • 10.1111/j.1600-0420.1996.tb00673.x


  • eng

Conference Location

  • Denmark