Acute Macular Neuroretinopathy Associated with COVID-19 Pandemic: A Real-world Observation Study

To evaluate the clinical and retinal imaging features of Chinese patients with acute macular neuroretinopathy (AMN) associated with COVID-19.

A prospective observational study.

Retinal imaging, including color fundus photography, near-infrared imaging (NIR), swept-source optical coherence tomography (SS-OCT), optical coherence tomography angiography (OCTA), and Humphrey perimetry, were conducted for each case.

All cases were included within the first three months following the pandemic outbreak. A total of 12 male patients (36.36 %) and 21 female patients (63.64 %) were prospectively recruited, and 29 cases (87.88 %) were bilaterally affected. The median interval between the onset of fever and the appearance of ocular symptoms was two days (range, 0.5-5.0 days). Apart from the outer retinal changes typical of AMN, changes in the inner retinal layers were observed, including intraretinal hemorrhage (8.06 %), cotton wool spots (9.68 %), and paracentral acute middle maculopathy (PAMM) (8.06 %). Smaller retinal inner nuclear layer hyperreflective speckles (RIHS) (41.94 %) were identified as a distinguishing feature from typical PAMM. Voids of vessel signals were found in the superficial (11.54 %), intermediate (82.69 %), and deep capillary plexus (98.08 %), and in the choriocapillaris (19.23 %) on OCTA. Humphrey perimetry illustrated central, paracentral, and peripheral scotomas. The occult lesions associated with AMN, PAMM, and some of the RIHS illustrated by OCT were visualized topographically and further confirmed by OCTA as perfusion defects.

An increase in AMN cases correlated with the SARS-CoV-2 outbreak. Additional features, including widespread inner retinal perfusion deficits, were observed and may serve as potential biomarkers for systemic microcirculation dysregulation in COVID-19.