The electroretinogram (ERG) is an electrical potential of retinal origin elicited by a visual stimulus. The basis of the ERG is the same photochemical process that leads to the neural response of the retina and the visual system1: photon absorptions in the photoreceptoral opsin pigments2. In addition, it is a purely retinal response that reflects the retinal physiology. It is not surprising tha...

PURPOSE To characterize multifocal electroretinogram parameters in patients with birdshot chorioretinopathy. METHODS Twenty-eight patients with birdshot chorioretinopathy consecutively included from 2006 to 2011 were matched to 27 healthy subjects for age, axial length, and lens status. Multifocal electroretinogram was prospectively evaluated using the Vision Monitor system. RESULTS Birdsho...

PURPOSE To determine the stimulus conditions required to elicit rod-driven, focal macular electroretinograms (rod FMERGs). METHODS A blue (lambda(max)=470 nm) stimulus, 5 degrees in size, was imaged at a luminance of 1.5 cd/m(2) on different regions of the human retina. Electroretinograms (ERGs) elicited by this stimulus were recorded from the light- and dark-adapted retina of four subjects w...

PURPOSE To compare the multifocal electroretinogram (ERG) system to conventional ganzfeld and focal ERGs obtained from patients with known retinal diseases to assess its clinical applicability. METHODS A multi-input system analysis was used to explore the field topography of ERG responses to local luminance modulation in patients with retinitis pigmentosa, pericentral pigmentary retinal dystr...

OBJECTIVE To assess the presence of normal or abnormal pattern electroretinogram (PERG) and visual evoked potential (VEP) responses in patients with ocular hypertension or open-angle glaucoma (OAG). DESIGN Retrospective, cross-sectional, case-control study. PARTICIPANTS Eighty normal control subjects (mean age, 51.77+/-6.04 years; 80 eyes), 68 ocular hypertension patients (mean age, 51.58+/...

Electrodiagnostic procedures have contributed to the certainty of diagnosis of a variety of neurological and neuromuscular diseases in animals. Widespread use of electrodiagnosis is limited by equipment costs and training of personnel. However, many of these procedures are used routinely in case work-ups in veterinary colleges or specialty practices. The purpose of this chapter is to present a ...