Abstract
Recent changes in lifestyle have caused an increase in extracranial internal carotid artery (ICA) lesions in Japan. The prevalence of severe ICA atherosclerosis with>50% stenosis in the Suita City was 4.4% (7.9% in men and 1.3% in women), being almost equal to that reported in developed western countries. Several clini-cal studies also indicated that atherothrombotic brain infarction particularly due to extracranial ICA lesions has rapidly been increasing in frequency in Japan. The ICA lesions have strong relationships to cardiovascu-lar risk factors and coronary heart diseases.
Carotid ultrasonography is a rapid, noninvasive and accurate way to examine ICA lesions. Diffusion MRI studies will provide new knowledge how ICA lesions produce infarcts particularly in borderzone areas.
The efficacy of carotid endarterectomy (CEA) in the management of severe ICA stenosis was established in US, Canada, and Europe, but not in Japan. Carotid artery stenting remains a matter of investigations. Clini-cal evidence on the effectiveness and limitations of such surgical interventions and medicla management with antithrombotic agents and HMG-CoA blockers should be collected for Japanese patients with ICA lesions.
