Carotid endarterectomy for treatment of tandem carotid stenosis in the presence of the anomalous origin of the occipital artery arising from the cervical internal carotid artery: a case report

INTRODUCTION: Branches from the cervical portion of the internal carotid artery are rare. In most cases, atherosclerotic stenosis is found at the bifurcation of the internal and external carotid arteries. However, when associated with atherosclerotic carotid artery disease, the origin of the rare branches arising from the internal carotid artery can be another site of stenosis. This report describes a rare case of such tandem carotid stenosis treated by carotid endarterectomy and the importance of the possibility of stenosis at the origin of the anomalous branch from the internal carotid artery. CASE PRESENTATION: A 73-year-old Japanese woman presented with transient left hemiparesis and vertigo. Magnetic resonance angiography seemed to indicate two stenotic lesions distal to the right internal carotid artery in addition to the origin of the right internal carotid artery, and angiography indicated tandem stenotic lesions of the internal carotid artery. The patient was successfully treated with right carotid endarterectomy, including the distal stenotic lesion of internal carotid artery, and postoperative angiography indicated that the occipital artery arose from the internal carotid artery. CONCLUSION: It is important to recognize rare cases of the anomalous origin of the occipital artery from the internal carotid artery and the possibility that the origin of such an anomalous occipital artery may be the cause of stenosis.