A Case of External Carotid Endarterectomy Followed by STA-MCA Bypass for Common Carotid Artery Occlusion

Abstract

Revascularization for symptomatic common carotid artery occlusion (CCAO) is advisable if hemodynamic ischemia symptoms are observed; however, there are no standardized treatment strategies because hemodynamic status varies in cases. We report the case of a 78-year-old patient with CCAO who presented with transient ischemic attack symptoms comprising right hemiparesis and aphasia and was treated with superficial temporal artery-middle cerebral artery (STA-MCA) bypass after carotid endarterectomy (CEA). Magnetic resonance imaging and angiography revealed occlusion of the left internal carotid artery (ICA) and multiple cerebral infarctions. Carotid ultrasonography, 3DCT angiography, and cerebral angiography indicated CCAO immediately before the carotid artery bifurcation. Additionally, the ICA was occluded to the petrous portion, while the external carotid artery (ECA) was opened from its origin via anastomosis with the vertebral artery. Moreover, N-isopropyl-p-[123I]iodoamphetamine (IMP) single-photon emission computed tomography (SPECT) revealed decreased cerebral blood flow while resting, and revascularization was planned to prevent recurrent ischemia. CCAO-ICA was long; therefore, restoration of antegrade intracranial blood flow was difficult. However, CCAO-ECA was short, indicating that the CEA was suitable for opening the ECA antegrade blood flow. An STA-MCA bypass was performed after CEA to open the CCAO-ECA. SPECT revealed improved postoperative cerebral blood flow while resting, and ischemic symptoms disappeared. In CCAO cases, as in the present case, combined CEA and STA-MCA bypass, which is a conventional technique, may prevent recurrent ischemia.