Multifocal electroretinogram indicates visual field loss in acute zonal occult outer retinopathy.

PURPOSE To report alterations of electrophysiologic tests, including the multifocal electroretinogram, in a case of acute zonal occult outer retinopathy. METHOD We recorded photopic, scotopic, and single-flash electroretinograms and a multifocal electroretinogram in a 47-year-old woman with acute zonal occult outer retinopathy in the right eye. RESULTS Her visual acuity was 20/20 in the right eye throughout the follow-up period. The electroretinograms indicated retinal impairment of the right eye, predominantly in the cones. The multifocal electroretinogram showed reduced responses corresponding to the visual field defect of the static perimetry. CONCLUSIONS In acute zonal occult outer retinopathy, impairment of the retinal area results in a visual field defect. The multifocal electroretinogram can be useful in determining the location of the defect.