Retinal Microvasculature Alteration in Paracentral Acute Middle Maculopathy and Acute Macular Neuroretinopathy: A Quantitative Optical Coherence Tomography Angiography Study

Abstract

Purpose: To present a series of idiopathic paracentral acute middle maculopathy (PAMM) and acute macular neuroretinopathy (AMN) cases and to compare the microvascular retinal status of PAMM/AMN eyes with those of healthy individuals. Methods: Six eyes with PAMM and two eyes with AMN in a total of six patients were included in this study. Multimodal retinal imaging, including optical coherence tomography angiography, was performed in all patients. The vessel density of the superficial capillary plexus and deep capillary plexus, as well as the area, circularity, and angle of the superficial foveal avascular zone (FAZ) were measured and compared with the same parameters in age-matched healthy individuals. Results: The optical coherence tomography angiography showed a decreased vessel density of both superficial capillary plexus and deep capillary plexus in PAMM/AMN eyes versus control eyes (12.2 ± 0.74 vs. 14.0 ± 1.62 mm−1 [P = 0.01] in superficial capillary plexus and 18.5 ± 1.2 vs. 20.2 ± 1.0 mm−1 [P = 0.02] in deep capillary plexus). There was no statistically significant change in the FAZ area between PAMM/AMN and healthy eyes. However, FAZ circularity in PAMM/AMN eyes was statistically significantly lower compared with healthy eyes (0.64 ± 0.09 and 0.77 ± 0.07, respectively; P = 0.01). The angle of FAZ was statistically significantly higher in PAMM/AMN eyes compared with healthy eyes (27.6 ± 16.2 and 11.2 ± 5.5°, respectively; P = 0.005). Conclusion: Paracentral acute middle maculopathy and AMN eyes demonstrated not only an isolated alteration of deep retinal circulation but also general nonspecific changes in retinal microvasculature, including a decrease in the vessel density of the superficial capillary plexus and distortion of the FAZ.

Prevalence of resolved paracentral acute middle maculopathy lesions in fellow eyes of patients with unilateral retinal vein occlusion

“…Earlier we described isolated resolved PAMM lesions in healthy asymptomatic patients which were associated with a general alteration of retinal microcirculation (Kulikov et al. ). If acute PAMM represents the mildest form of ischaemic retinal vascular injury which shares common systemic risk factors with severe retinal vascular events (branch or central retinal vein occlusions), then asymptomatic resolved PAMM lesions should be associated those events.…”

Paracentral acute middle maculopathy and acute macular neuroretinopathy following SARS-CoV-2 infection

“…PAMM OCT changes are seen in various retinal vascular diseases, such as retinal vein and artery occlusion. OCT angiography (OCT-A) has provided further support for a retinal vascular aetiology in PAMM and AMN [10][11][12][13][14][15]. Projection resolved OCT-A distinguishes the intermediate from the deep capillary plexus, which run either side of the inner nuclear layer.…”

Bilateral Acute Macular Neuroretinopathy in a Young Patient: Imaging and Visual Field during Two-Year-Follow-Up

“…The most creditable hypothesis is that these changes result from local compromise of the DCP which provides retinal perfusion to the zone between the retinal and choroidal circulations, with a reperfusion in late stages [36]. This concept of DCP ischemia causing AMN is strongly supported by previously identified risk factors for AMN [2,16].…”

“…It has been shown in previous studies that retinal lesions in AMN represent circumscribed areas of hypoperfusion that lead to atrophy of the outer nuclear layer in these areas, in contrast to paracentral acute middle maculopathy (PAMM) where the inner layers are involved [16]. In particular, the AMN lesions may develop at the junction of the outer plexiform layer (OPL) and outer nuclear layer (ONL) with associated outer macular disruption [17,18].…”