Multimodal Imaging of a Case of Acute Annular Outer Retinopathy

Background: Acute annular retinopathy (AAOR) is a rare entity showing grayish spots with annular lesions. We report the clinical characteristics of a patient with AAOR derived by using multimodal imaging including spectral-domain optical coherence tomography (OCT), fundus autofluorescence (FAF), and an adaptive optics fundus camera. Case: A 56-year-old man who had fever one month and a half before presenting. He noticed bilateral visual loss after lowering of fever. Clinical findings: Grayish white rings of different sizes were seen in the posterior fundus. Margin of the lesion showed hyperautofluorescence. OCT demonstrated an indistinct ellipsoid zone, disruption of external limiting membrane, and bulging of the retinal pigment epithelium in the annular lesions. We found hyperreflective foci in the inner retina and an indistinct interdigitation zone on the OCT images and indistinct cone mosaic patterns on the AO images at an ophthalmoscopically normal fovea in the left eye. Conclusion: Multimodal imaging showed the damage in the photoreceptors and the retinal pigment epithelium at the annular lesions. OCT and AO imaging can demonstrate abnormal findings in ophthalmoscopically normal areas in eyes with AAOR.