Electrophysiological tests in the assessment of visual disorders

Abstract

RESUMENLos tests electrofisiológicos ayudan al estudio de la función visual. El objetivo de este trabajo es presentar las bases fisiológicas, aspectos técnicos e indicaciones generales de los tests que se practican de forma habitual en nuestro medio.El electorretinograma-flash refleja la función de los fotorreceptores y de capas más externas de la retina. El electrorretinograma-patrón informa de las células ganglionares retinianas y puede identificar alteraciones maculares que simulan neuropatías ópticas. El electrooculograma valora la función del epitelio pigmentario y capas externas de la retina y diferencia la enfermedad de Best de otras bestrofinopatías. Los potenciales evocados visuales informan de las vías ópticas y son, sobre todo, útiles en la valoración del nervio óptico.Palabras clave. Electrorretinograma-flash. Electrorretinograma-patrón. Electrooculograma. Potenciales evocados visuals. ABSTRACTSome electrophysiological tests are helpful in the assessment of visual disorders. The physiological basis, technical aspects and general indications of those available at most neurophysiology services are reviewed.The Full-Field electroretinogram reflects photoreceptor and outer retinal function. The Pattern electroretinogram assesses retinal ganglion cell function and can identify macular dysfunction mimicking optic nerve disease. The electro-oculogram is a test of function of the outer retina and retinal pigment epithelium; it differentiates Best's disease from all other bestrophinopathies. Visual evoked potentials evaluate the visual pathway and are especially helpful in the evaluation of the optic nerve.

Changes in 24 h Rhythmicity of Spontaneous Locomotor Activity in the Triple Transgenic Mouse for Alzheimer’s Disease (3xTg-AD) in a Jet Lag Protocol: Correlations with Retinal Sensitivity

“…In the retinal outer layer, the response of photoreceptors (mainly rods, but also cones) (wave A), bipolar cells, and Müller cells (wave B) takes place. Under photopic conditions, the response is given only by cones [ 54 ]. However, this type of ERG is useful to identify alterations in the functionality of extracerebral neural tissue, which supports the premise that the retina is a “window” to study the brain.…”