OCULAR ISCHEMIC SYNDROME IN THE SETTING OF NORMAL CAROTID DUPLEX ULTRASOUND.

Purpose: The aim of this study was to describe two cases of ocular ischemic syndrome (OIS) that were initially ruled out because of a negative carotid duplex ultrasound but eventually confirmed by angiography studies.

Methods: This is a case series.

Results: Case 1: A 67-year-old woman presented with symptoms suggestive of OIS, but carotid duplex ultrasound was negative, and the patient was diagnosed with occlusive retinal vasculitis due to retinal nonperfusion and vascular leakage on fluorescein angiography. Immunosuppressive therapy was initiated, but her symptoms did not improve. Computerized tomography angiography was significant for severe osteal stenosis of the aortic arch vessels. Left common carotid angioplasty and stenting resulted in complete resolution of the symptoms and vascular leakage of the left eye. Case 2: A 41-year-old man with cryoglobulinemia-associated vasculitis complained of symptoms consistent with OIS, which was initially ruled out through a negative carotid duplex ultrasound. Fluorescein angiography revealed delayed arterial filling with poor retinal perfusion. Magnetic resonance angiography revealed ophthalmic artery stenosis, which was attributed to the underlying systemic vasculitis.

Conclusion: Computerized tomography angiography or magnetic resonance angiography should be performed to rule out OIS if duplex ultrasound is negative in the setting of high clinical suspicion. Carotid ostial and ophthalmic artery stenoses are rare but possible causes of OIS.