gms | German Medical Science

102. Jahrestagung der DOG

Deutsche Ophthalmologische Gesellschaft e. V.

23. bis 26.09.2004, Berlin

Multifocal on- and off-responses after stimulation with a LED-screen in a patient with CSNB classified as complete Schubert-Bornschein type

Meeting Abstract

  • corresponding author D. Leifert - Augenspital Basel, Schweiz
  • M. Todorova - Augenspital Basel, Schweiz
  • C. Prünte - Augenspital Basel, Schweiz
  • A. Palmowski-Wolfe - Augenspital Basel, Schweiz

Evidenzbasierte Medizin - Anspruch und Wirklichkeit. 102. Jahrestagung der Deutschen Ophthalmologischen Gesellschaft. Berlin, 23.-26.09.2004. Düsseldorf, Köln: German Medical Science; 2004. Doc04dogP 152

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Veröffentlicht: 22. September 2004

© 2004 Leifert et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Objective

To our knowledge this is the first report of the application of a light emitting diode (LED) screen to elicit multifocal on-off responses in a patient presenting with the complete type of congenital stationary night blindness (cCSNB).

Methods

Applying conventional ERG set-ups, a 63-year-old woman was recently diagnosed with cCSNB. To confirm our diagnosis we were interested in the on- and off-responses which allow for better differentiation between the complete and the incomplete type, also known as CSNB type 1 and 2. In addition we focused on regional diversity of the responses applying a multifocal ERG (Retiscan™) approach. Stimuli (on ~100ms, off ~100ms) were generated on a screen consisting of 32x32 LED elements. Latencies (ms) and response densities (nV/deg2) of the on- and off-responses were recorded from 61 retinal locations. Three response averages were analysed: The central field (central 7 hexagons), the two adjoining ring areas averaged as one group and the outer ring average. Results were compared to control subjects.

Results

Consistent with full-field-recordings, on-responses (P1-ampitudes) were reduced at all eccentricities whereas off-responses showed no reduction. The on-off ratio was therefore decreased. Applying a fast stimulation mfERG (stimulus length:13.3ms) increased latencies of the P1 peak, which is thought to be formed by both on- and off-bipolar cells, have been reported before in cCSNB. With the slow on-off stimulus used here, we found that the P1-on-latencies were increased in all areas, but interestingly, off-latencies were normal.

Conclusions

The LED screen in mfERG proofs to be a valuable tool by providing precise generation of on-off stimuli. Therefore it facilitates for example the differentiation between CSNB subtypes. Our recordings support results obtained with full-field-recordings and in fast mfERG set-ups, furthermore they add topographical information regarding the off-response. Moreover, this approach may provide new information on regional diversity in these disorders. However, further studies are needed.

Supperted by a grant by Pfizer (TM, PA).