[Electroretinogram: technique and clinical applications]

The retina is a neuronal membrane that covers the posterior part of the eye chamber and is formed by several layers. The retinal function can be synthesize as the light translation into nervous impulses in the optic nerve.

The ERG is the expression of the changes of the electrical potential in the retina after a luminous stimulus. There are different types of retinal stimulators specially flash, ganzfeld and pattern which are the most used in the clinical neurophysiological explorations.

We expose the obtained responses, the morphology, amplitude and latencies of the (a) and (b) waves in scotopic and photopic conditions with ganzfeld or flash stimulator. In the ERG pattern we describe the waves for the transitory ERGP as well as for the Steady-State ERGP. We refer to the protocols proposed by the International Society of Electrophysiology of Vision (ISCEV). We mention the clinical applications of these techniques and we give our personal experience in diseases such retinitis pigmentosa, maculopathies, retinal degenerations, vascular diseases, cataracts and traumatic lesions of the retina.