Acute macular neuroretinopathy is a rare, idiopathic condition, originally described by Bos and Deutman in 1975, and characterized by acute onset, paracentral scotoma with dark-reddish, wedge-shaped fundus lesions around the fovea. Characteristic spectral-domain optical coherence tomography includes hyperreflectance of the outer retinal layers in the acute phase, particularly the outer plexiform layer and the outer nuclear layer.
The acute onset of the symptoms and association with the known circulatory risk factors has implicated vascular compromise as a potential etiology. Localization of abnormalities to the outer retina led to speculation that the deep retinal capillary plexus ischemia may play a role, especially owing to the lack of visible retinal pigment epithelial or choroidal changes on optical coherence tomography or conventional fluorescein angiography.
However, the advent of optical coherence tomography angiography provided further evidence that vascular insult to the choriocapillaris is involved in the pathogenesis of acute macular neuroretinopathy.
Here, we report the first evidence of deep retinal capillary plexus defect on optical coherence tomography angiography in two patients with acute macular neuroretinopathy.
Prospective cohort study of 2 patients with diagnosis of acute macular neuroretinopathy. Evaluation included fundus photography, fluorescein and indocyanine green angiography, en face near-infrared imaging, fundus autofluorescence, spectral-domain optical coherence tomography, optical coherence tomography angiography, visual field and full-field electroretinography.
Two eyes from 2 patients with a diagnosis of acute macular neuroretinopathy were included. Duration of follow-up was 6 months. All eyes had deep retinal capillary plexus flow void on optical coherence tomography angiography that topographically corresponded to regions of abnormal hyperreflectance of the outer retina layers on spectral-domain optical coherence tomography. For each patient, these areas of deep retinal capillary plexus flow void persisted during the follow-up period. The hyperreflectance of the outer plexiform layer and outer nuclear layer on spectral-domain optical coherence tomography was observed to improve, with thinning of this layers during follow-up.
These findings suggest that deep retinal capillary plexus flow void on optical coherence tomography angiography is seen in patients with acute macular neuroretinopathy, offering further evidence of a vascular mechanism.
This is the first cohort study revealing that deep retinal capillary plexus ischemia seen on optical coherence tomography angiography is involved in the pathogenesis of acute macular neuroretinopathy.
