BACKGROUND: Unilateral acute idiopathic maculopathy (UAIM) is a rare entity, in which an inflammatory process involves the macular retinal pigment epithelium (RPE) and outer retina. It represents a wide spectrum of ocular findings not consistently present in all patients, which may lead to difficulties in the recognition of the condition. METHODS: This observational case report presents the third-generation optical coherence tomography (StratusOCT) and multifocal electroretinogram (mfERG) findings in a 31-year-old woman with UAIM in the acute phase as well as two months later, and discusses the role of StratusOCT in the diagnosis. RESULTS: In the acute phase, StratusOCT demonstrated abnormal heterogeneous hyperreflectivity and thickening at the level of the outer retina and RPE in the foveal region. Two months after the initial presentation, StratusOCT examination showed a subfoveal area of homogeneous hyperreflectivity that extended from the RPE to the outer retinal layers with posterior shadowing, and sparse points of hyperreflectivity at several different levels of the neurosensory retina, including its superficial layers. The foveal retinal thickness during the acute phase was thicken compared with that after resolution. Seven days after the initial evaluation, mfERG showed severely reduced N1-P1 amplitudes with normal latencies in the region corresponding to the affected area of the papillomacular bundle and fovea. Two months later, mfERG results were normal. CONCLUSIONS: StratusOCT provided valuable information, allowing for the exclusion of other disorders that might mimic UAIM. mfERG findings were consistent with transient outer retinal dysfunction as the cause of visual loss. We are unaware of previous reports of UAIM studied by these methods and could find no reference to them in a computerized search using MEDLINE.