OCULAR ISCHEMIC SYNDROME DURING CAROTID BALLOON OCCLUSION TESTING

The use of a double-lumen balloon catheter for temporary occlusion tes ting of the internal carotid artery permits simultaneous perfusion of the distal internal carotid artery (and ophthalmic artery) with hepari nized saline. If saline is infused too rapidly, the result may be tota l or partial replacement of oxygenated blood within the ophthalmic art ery. This replacement may produce the signs and symptoms of ocular isc hemic syndrome. These include ipsilateral orbital pain and progressive uniocular visual loss. Simple technical adjustments in the performanc e 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 sugg est that a thromboembolic complication has occurred. Awareness of the occurrence of this syndrome should prevent confusion concerning the pr edictive result of provocative carotid occlusion testing.