Clinical electroretinography by the skin electrode and signal averaged method

Conventional electroretinography requires the application of a ring or contact electrode to the anaesthetized cornea. A simplified method for routine clinical electroretinography is described. Skin electrodes are used, signals are appropriately filtered, amplified, passed to a signal averager and displayed on an oscilloscope. Sixteen sweeps are employed and a wave form similar in appearance and frequency content to that obtained by the corneal electrode method, is obtained. Values for the light and dark adapted eye in normal subjects (pupils undilated), are provided and the findings in the stages of retinitis pigmentosa and in other disease states, are noted.