Mapping of VEPs and ERG responses to punctual stimulations in the visual field.

Abstract

Visual field projection maps were obtained using retinal and cortical EP amplitude values. Single meridian investigations were also performed. Stimulation was done with punctual photic stimuli delivered by the LED perimeter built for the purpose. Schedule with 28 stimulation loci was adopted. The B wave of the average ERG and P100 component of the cortical VEP were measured. The maps were obtained by interpolation of amplitude values on a grid of 21 x 21 characters. By comparing the retinal and cortical visual field maps, conclusions regarding the normality of visual structures (peripheral or central) can be drawn. Our procedure adds to the previous data on visual field investigation (cynetic or static) important elements concerning vision electrophysiology.