skip to main content
Idioma:

Grating visual acuity development of brazilian terriers using the sweep-VEP method

F M Moreno-Carmona M F Costa; Dora Selma Fix Ventura; P S M Barros; Annual Meeting of the Association for Research in Vision and Ophthalmolgy of Genetic (2004 Lauderdale)

Lauderdale v. 45, p. E-Abstract 4313, 2004 Investigative Ophthalmology and Vision Science

Lauderdale 2004

Localização: IP - Instituto de Psicologia    (Resumo digitado (AM=VDo/89) ) e outros locais(Acessar)

  • Título:
    Grating visual acuity development of brazilian terriers using the sweep-VEP method
  • Autor: F M Moreno-Carmona
  • M F Costa; Dora Selma Fix Ventura; P S M Barros; Annual Meeting of the Association for Research in Vision and Ophthalmolgy of Genetic (2004 Lauderdale)
  • Assuntos: PERCEPÇÃO; VISÃO
  • É parte de: Lauderdale v. 45, p. E-Abstract 4313, 2004 Investigative Ophthalmology and Vision Science
  • Descrição: Purpose: to measure the development of grating visual actify (VA) in Brazilian Terrier pup by sweep visual evoked potentials (sVEP). Methods: Grating VAs Brazilian Terrier pups (n=6; male, 3 female), from the same litter and one adult (matrix) were measured. Sweep- VEPs (NuDiva) were recorded from two active electrodes placed on the scalp at O1 and O2, a reference electrode at Oz and a group electrode at Cz. The stimuli were pattern reversal square wave gratings at a rate of 6Hz, ranging from .2 to 15 cicles per degree. The mean monitor luminance was 159.3 cd/m2. The VAs were measured weekly from the 4th to the 13th week. Viewing distance was 50cm and the pup was positioned on the lap of the investigator with the head gently supported to maintain the eyes in front of the video monitor (Dotronix D788). The test was performed in a darkened room without mydriatic, sedative or anesthetic drugs. Results: The mean VA ranged from 2.28±0.16 cpd (equivalent to 20/260 Snellen VA) at the 4th week to 8.59±0.13 cpd (20/70) at the 13th week. Adult VA was 8.7 cpd steeper up to the 7th week than afterwards. The rate of increase gradually declined up to the 10th week. An ANOVA comparing the weekly results showed significance for all results between the 4th and 10th weeks (f=479.3 p<.001) and lack of significance thereafter. There was a high positive correlation between the VA and body weight (Pearson R=.92; p<.001). Thus the course of development of VA paralleled that of body weight, with a high rate of increase in the first 7 weeks, followed by declining rates. Conclusions: The Sweep-VEP method offers a rapid and reliable procedure for the quantification of grating VA in pups, without the need for sedation. Pup VA reached adult values at the 10th week of life. The adult VA measured (20/70) is in accordande with estimates of VA of dogs in other studies. Their red-green system. Despite this loss and the dramatic visual acuity impairment, their discrimination
    performance in the tritan axis remains almost intact or much less affected, following the trend observed in the LHON carriers. These findings show that the mechanisms responsible for LHON are highly specific within the visual system.
  • Editor: Lauderdale
  • Data de criação/publicação: 2004
  • Formato: p. E-Abstract 4313.
  • Idioma: Inglês
Links
Voltar para lista de resultados
Ir para página anteriorAnterior Resultado  4

  • Realização: ABCD-USP USP   Logos de Redes Sociais: Freepik

Buscando em bases de dados remotas. Favor aguardar.