Us efulness of Standard Electro retinogram in the Early Diagnosis of Diabetic Retinopathy: Analysis using Receiver Operating Characteristic(ROC) Curve

ABSTRACT

Authors recorded standard electroretinogram in two groups of diabetic patients. Group A, consisted of 60 eyes with no visible diabetic retinopathy and Group B, 30 eyes with mild nonproliferative diabetic retinopathy. The electroretinogram was recorded according to the standard electroretinogram procedure recommanded by the ISCEV. In rod and cone response, the amplitude of b wave were 329.0+/-46.9 microvoltin Group A and 308.8+/-37.8 microvoltin Group B. The implicit time of b wave were 40.5+/-3. 0microvoltin Group A and 45.8+/-5.4microvolti n Group B. The summed amplitude of oscillatory potentials were 125.7+/-38.7microvolt in Group A and 112.0+/-17.7microvoltin Group B. Above results indicate that for the disgnostic criteria for diabetic retinopathy, the amplitude and implict time of b wave, and the summed amplitude of oscillatory potentials in maximal combined response were useful. On receiver operating characteristic(ROC) curves in maximal combined response, cut off value for the amplitude and implicit time of b wave were 315 microvoltand 42ms espectively. Cut off value for the summed amplitude of oscillatory potentia-als was 118 microvolt. In results, on ROC curve, the implicit time of b wave in maximal combined response was most accurate, and the summed amplitude of oscillary potentials was the next, followed by the amplitude of b wave in the maximal combined response.