2007 ICD-9-CM Procedure 95.21 Electroretinogram [erg] Recording of electric potentials in the retina after stimulation by light. 95.21 is a specific code that can be used to specify a procedure 95.21 contains 2 index entries View the full Volume 3 95.* hierarchy Index entries containing 95.21: Electroretinogram (ERG) 95.21 ERG (electroretinogram) 95.21