Abnormal Electroretinogram in Cocaine-Dependent Patients: Relationship to Craving

Background. The retina contains high concentrations of dopamine.We previously reported that recently withdrawn cocaine-dependent patients had significantly reduced blue cone b wave amplitude responses on the electroretinogram (ERG). In this study we wished to examine if there was a relationship between cocaine craving and reduced blue cone b wave ERG responses. Methods. A series of 14 recently withdrawn cocaine-dependent patients completed a 45-item cocaine craving questionnaire shortly before the ERG. Results. Cocaine dependent patients who had a reduced (<0.5 microvolts) blue cone b wave ERG response had significantly higher cocaine craving scores than patients without a reduced blue cone ERG response.There was also a significant negative correlation between blue cone b wave amplitude responses and scores on the cocaine craving questionnaire. Conclusion. A reduced blue cone b wave ERG response may identify recently withdrawn cocaine-dependent patients with biological dysregulation and increased cocaine craving.