Potencial evocado visual por flash em cães, ovinos e equinos

• Autor(a) principal: Palumbo, Mariana Isa Poci [UNESP]
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/123708; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/12-06-2015/000831505.pdf
• topic: Visão - Testes; Olhos - Doenças; Animais - Doenças; Neurologia veterinaria; Eye - Diseases and defects

The visual evoked potential (VEP) is an electrodiagnostic test that detects and records the electrical activity in the visual central pathway. The VEP has applicability in veterinary neurology, but the test is not routinely used in Brazil. The aims of this study were obtain normative data of flash-VEP from dogs, sheep and horses. PEV were obtained with monopolar needle electrodes placed in O1 and O2 (active), Fpz (common reference) and Cz (ground). VEP obtained from 17 dogs, 17 sheep and 17 horses were included in the normative study. Both eyes were evaluated, totaling 34 results in each species. The most consistent result in all tests was an electropositive deflection, with a mean latency of 55.4 ms in dogs (P55), 63.75 ms in sheep (P63), and 52.76 ms in horses (P53). All tests also allowed the identification of 2 electronegative deflections: N31 and N75 in dogs, N42 and N86 in sheep, N38 and N72 in horses. The F-VEP was also performed in 3 horses before and during sedation with different doses of xylazine (0.4 and 1.1 mg/kg) or detomidine (0.005 and 0.014 mg/kg). Sedation significantly affected the results, even at the lower dose. It was concluded that the BAEP is a useful and safe test to evaluate the visual central pathway. The obtained data and methodology used in this study will be useful for comparison with the results obtained from animals with different injuries related to the central visual pathway