Retinal function assessment in alcohol use disorder patients

Objective. Retinal injury induced by ethanol consumption has been previously reported in animal models, including biochemical, histological and functional alterations. These results need to be clinically tested in alcoholic patients which do not report several systemic or ophthalmic diseases. Methods. Six patients with alcohol use disorder were recruited from an ‘Alcoholism Treatment Unit’. All of them with active alcohol consumption when the study was conducted or that had stopped drinking six months prior to the study, with no ocular disease or visual acuity alterations. All patients underwent fundus photography, optical coherence tomography (OCT) as well as visual field test. Electrophysiological tests were conducted to check retinal function: Ganzfeld Electroretinogram (ERG), Pattern Electroretinogram (PERG), Multifocal Electroretinogram (mfERG), and also Visual Evoked Potential (VEP). Results.Visual acuity was normal in all cases as well as fundus photography and visual field test. The OCT showed a mild decrease in the retinal nerve fiber layer thickness average in three patients. Five patients showed impairments in mfERG response, decreased amplitude in ERG response and no significant alterations in PERG and VEP. Conclusion. Although standard ophthalmic tests did not show signs of an ocular disease, the study of electrical function showed different impairments in almost all patients. The alterations reported in mfERG and ERG recordings could reflect inner retina injury, thus supporting the possible existence of an alcoholic retinopathy. Further studies with larger number of subjects are necessary to assess the specific impact of other factors such as tobacco or nutritional status on patients with alcohol use disorder