Objective: To describe the detection of emboli to the retrobulbar circulation using orbital color Doppler imaging in patients with central retinal artery occlusions (CRAO) without visible retinal emboli.
Design: Noncomparative, retrospective, observational case series.
Patients and methods: Twenty-nine patients with CRAO, without funduscopic evidence of embolic material within the retinal arterioles, underwent neuroophthalmic examination and evaluation with orbital color Doppler imaging.
Main outcome measures: The detection of retrobulbar plaques using orbital color Doppler imaging.
Results: Nine of 29 (31%) patients with CRAO demonstrated hyperechoic retrobulbar plaques. All nine patients had visual acuity of counting fingers or worse at presentation. Six of the nine patients (67%) had a history of hypertension, and seven (78%) had coronary artery disease as vascular risk factors for arterial occlusive disease. Two of the nine patients (22%) subsequently died from cardiac-related events.
Conclusions: This study demonstrates that orbital color Doppler imaging is an important diagnostic procedure for establishing embolism as the cause of CRAO when no emboli are visible in the retinal circulation. This noninvasive technology enables prompt differentiation of embolic disease from arterial occlusion caused by intrinsic atherosclerosis, vasospasm, or vasculitis from giant cell arteritis. Recognition of emboli has important management implications for these patients.