Clinical features of acute macular neuroretinopathy induced by Omicron

AIM: To observe the clinical features of acute macular neuroretinopathy(AMN)induced by Omicron.METHODS: A retrospective study. A total of 9 patients(18 eyes)diagnosed with AMN from December 2022 to January 2023 in the Hospital of Chengdu University of Traditional Chinese Medicine were included. Patients underwent spectral-domain optical coherence tomography(SD-OCT), fundus fluorescein angiography(FFA), fundus photography, autofluorescence(AF), infrared reflectance(IR), optical coherence tomography angiography(OCTA)and multicolor, etc. Furthermore, they were followed up for 1～3mo and observed the prognosis.RESULTS: The initial symptom of the Omicron-induced AMN was the sudden onset of central/paracentral scotoma in the eyes with or without impaired vision and metamorphopsia, and the scotoma could persist for at least 3mo. The image features of AMN are as follows. First, the SD-OCT examination showed the rupture of outer retinal layers, scattered hyperreflective lesions, and atrophy of outer retinal layers. In severe cases, hyperreflective lesions were seen in the inner nuclear layer(INL)or with microcystic cavities under the retinal pigment epithelium(RPE). Second, the OCTA examination demonstrated the decreased blood flow density of the deep capillary plexus(DCP)of the macula. Third, the IR examination showed the weak reflection of lesion areas. Fourth, the fundus photography demonstrated the localized brown wedge-shaped lesion.CONCLUSIONS: The Omicron-induced AMN is mostly found in young females, and the characteristic manifestation of fundus is damage to the outer retinal layers. The extent of fundus lesions is related to the systemic inflammatory response and ocular microcirculatory changes after infection. The multimodal fundus image examination and a history of Omicron infection are helpful to diagnose the Omicron-induced AMN.