En Face Optical Coherence Tomography Analysis to Assess the Spectrum of Perivenular Ischemia and Paracentral Acute Middle Maculopathy in Retinal Vein Occlusion

Purpose To assess the spectrum of perivenular ischemia in eyes with retinal vascular obstruction (typically central or hemicentral retinal vein obstruction) using en face optical coherence tomography (OCT). Design Retrospective observational case series. Methods Eyes with recent retinal vascular occlusion illustrating paracentral acute middle maculopathy (PAMM) in a perivenular fern-like pattern with en face OCT were evaluated in this study. Multimodal retinal imaging including en face OCT segmentation of the inner nuclear layer was performed in all patients. Color fundus photography and fluorescein angiography (FA) images were used to create a vascular overlay of the retinal veins vs the retinal arteries to map the distribution of PAMM with en face OCT analysis. Results Multimodal retinal imaging was performed in 11 eyes with acute retinal vascular obstruction. While 7 eyes demonstrated obvious findings of retinal vein obstruction (5 with central and 2 with hemicentral retinal vein occlusion), 4 eyes were unremarkable at presentation. En face OCT analysis demonstrated a spectrum of perivenular PAMM illustrating a fern-like pattern with sparing of the periarteriolar area in all cases. Conclusion En face OCT may illustrate a remarkable perivenular pattern of PAMM in eyes with retinal vascular obstruction even in the absence of significant funduscopic findings. Perivenular PAMM with en face OCT demonstrates a wide spectrum of variation with narrow fern-like perivenular lesions at the mildest end and more diffuse lesions with only periarterial sparing at the most severe end of the spectrum. Arterial hypoperfusion secondary to outflow obstruction from a central retinal vein obstruction appears to be the most common cause of this presentation, although primary arterial hypoperfusion may also be an etiology.