Indocyanine green (ICG) angiography of cervical carotid artery stenosis was performed and the contrast patterns were analyzed. The subjects were 18 patients who had undergone carotid endarterectomy (CEA) since August 2009. Before arteriotomy, ICG angiography was performed and monitored. One patient who underwent ICG angiography of the cervical vessels during high-flow bypass of a ruptured cerebral aneurysm acted as a control. On ICG angiography of the control patient, the vascular lumen was first filled with ICG, after which the arterial component of the vasa vasorum was slowly contrast-enhanced, followed by contrast enhancement of the venous component, and finally uniform contrast enhancement of the arterial wall. The vasa vasorum were contrast-enhanced in an annular conformation along the short axis of the internal carotid artery. In CEA patients, the arterial component of the vasa vasorum was quickly contrast-enhanced after ICG filling of the vascular lumen, with a non-homogenous vascular network formed by branches of the vasa vasorum at the atheroma site, followed by contrast enhancement of the venous component and, finally, by patchy contrast enhancement of the entire arterial wall. The vasa vasorum were contrast-enhanced in a virtually radiating conformation along the long axis, mainly around the common carotid bifurcation. Similar results were also obtained from analysis of the time-intensity curve with Flow 800.
ICG angiography findings in severe cervical carotid artery stenosis suggested that the vascular structure of the arterial wall had transformed from a normal condition to a pattern of nutrient supply to the atheroma.
