Is there a potential role for hyoid bone compression in pathogenesis of carotid artery stenosis?

Abstract

BACKGROUND: Blood flow turbulence and increased shear stress, particularly at sites of sudden, marked arterial wall changes, are significant hemodynamic parameters in the pathogenesis of atherosclerosis. We present a case in which we found the hyoid bone protruding into the carotid vessels and may have been contributing, in part, to atherosclerotic carotid stenosis. CASE PRESENTATION: An 85-year-old woman presenting with left arm and leg weakness consistent with right hemispheric transient ischemic attack. Magnetic resonance arteriography (MRA) and carotid non-invasive studies revealed a 90% stenosis of the right internal carotid artery. At surgery, the hyoid bone on the right side was projecting into the internal carotid artery, causing indentation. There was associated rotation of the internal and external carotid arteries from their normal position. Right carotid endarterectomy was performed and the lateral one-third of the hyoid bone excised to alleviate the external compression. Postoperative spiral computerized tomography (CT) scan of the carotid vessels demonstrated the extent of hyoid resection as well as rotation of the external and internal carotid arteries. CONCLUSIONS: We suggest the possible contribution of hyoid bone compression to the pathogenesis of atherosclerotic carotid artery stenosis. This report also highlights the diagnostic value of CT angiography in the assessment of carotid artery occlusive disease.