This healthy 10YO female presented with a 3-month history of decreased vision in her left eye. Vision was 20/15 in her normal OD and 20/200 OS.
Pseudocolor SLO imaging shows tangles of markedly dilated and tortuous vessels, which extend into the superotemporal midperiphery and obscure the optic disc. The retinal vessels are sheathed nasally and superiorly. Fluorescein angiography shows no leakage with ischemic retina distal to the anomalous vessels. Neurologic imaging was negative.
Learning Points:
A retinal arteriovenous malformation (AVM) is a congenital connection between an artery and a vein without an intervening capillary network. These lesions appear along a spectrum ranging from small, isolated lesions to the large ‘bag of worms’ appearance as seen in our patient. These more extensive lesions are usually part of the Wyburn-Mason Syndrome, which includes vascular lesions in the eyes and midbrain.
Retinal venous malformations, also known as retinal macrovessels, are now thought to represent an AVM (Pichi et al., JAMA Ophthalmol 2018;136:372-379). These lesions can rarely bleed or cause retinal venous occlusions. The diffuse vascular sheathing may represent such a prior occlusion.
