This 57YO male presented with 3 weeks of blurred vision in his left eye. Vision was 20/20 OD and 20/40 OS. Anterior segments showed a moderate nuclear sclerotic cataract OS, accounting for his acuity. The left fundus was normal.
Color photography shows a large aberrant retinal vein, which crosses the horizontal meridian and drains nearly the entire right macula. There is a small vascular loop superiorly.
Learning Points:
Retinal vessels virtually always respect the horizontal meridian. Retinal venous malformations are congenital anomalous vessels that, by definition, cross the horizontal. Originally described by Gary Brown et al as congenital retinal macrovessels (Arch Ophthalmology 1982;100:1430-1436), these vessels are usually located in the macular region and are virtually always venous. These lesions are now called retinal venous malformations, since about one-quarter of patients have associated venous anomalies in the brain (Pichi et al, JAMA Ophthalmol 2018;136:372-379).
