Ocular ischemic syndrome during carotid balloon occlusion testing

The use of a double-lumen balloon catheter for temporary occlusion testing of the internal carotid artery permits simultaneous perfusion of the distal internal carotid artery (and ophthalmic artery) with heparinized saline. If saline is infused too rapidly, the result may be total or partial replacement of oxygenated blood within the ophthalmic artery. This replacement may produce the signs and symptoms of ocular ischemic syndrome. These include ipsilateral orbital pain and progressive uniocular visual loss. Simple technical adjustments in the performance of the occlusion test can prevent the development of this syndrome. Failure to recognize the cause of the observed visual loss may produce the false impression of a positive occlusion test or may falsely suggest that a thromboembolic complication has occurred. Awareness of the occurrence of this syndrome should prevent confusion concerning the predictive result of provocative carotid occlusion testing.