Green vessel signal on multicolor imaging as an early sign of ischemic vasculitis in IRVAN Syndrome: A case report.

Purpose: Idiopathic retinitis, vasculitis, aneurysms, and neuroretinitis (IRVAN) syndrome is typically diagnosed after characteristic intravenous fluorescein angiography (IVFA) findings develop. This case demonstrates that identifying a green intravascular and perivascular signal on multicolor fundus imaging may be a potential noninvasive imaging sign for ischemic retinal vasculitis in IRVAN. Observations: A 55-year-old female presented with bilateral optic disc edema and subtle peripapillary retinal vascular changes. Multicolor imaging showed a distinct green intravascular and perivascular signal before undergoing IVFA evaluation. Subsequent IVFA ultimately showed peripheral capillary nonperfusion, microaneurysms, and leakage consistent with IRVAN. Conclusions and importance: This case demonstrates the potential utility of multicolor imaging for detecting subtle vascular abnormalities that are not apparent on clinical examination or on traditional color fundus photography. Recognition of this green vessel signal may serve as an imaging sign of vascular wall changes, prompting consideration of IRVAN and guiding timely further angiographic evaluation in patients presenting with atypical optic disc edema or suspected retinal vasculitis.