Abstract
One of the characteristics of occlusive cerebrovascular disease in Japan is a high frequency of involvement of the extracranial and intracranial vessels (tandem lesion). This study involved 18 patient with tandem lesions who had a carotid endarterectomy (CEA).
Besides carotid bifurcation stenosis and/or ulcer on the side corresponding to the ischemic symptoms, the sites of other angiographic lesions were: contralateral carotid bifurcation stenosis or occlusion, 11; ipsilateral carotid siphon stenosis, 9; contralateral carotid siphon stenosis, 3; ipsilateral middle cerebral artery stenosis, 3; and vertebrobasilar artery stenosis or occlusion, 2. The mean followup period was 2.9 years.
Following superficial temporal artery-middle cerebral artery bypass surgery three patients developed new ischemic symptoms responsible for the asymptomatic ulcerative lesion of the carotid bifurcation, which was improved by CEA. One patient had a minor stroke three years after CEA because of recurrent stenosis and another revealed a progression of an asymptomatic carotid stenosis without any neurological aggravation; however, these two patient were uniformly relieved of symptoms with the use of anticoagulant agents. Thirteen other patients not only demonstrated no symptomatic deterioration but also no angiographic worsening.
The high incidence of resolution of intracranial stenosis or occlusion during the period of study indicates that surgery should not be contemplated until a sufficient interval has elapsed to exclude the chance of recanalization. The resolving carotid siphon stenosis following CEA and changes in intracranial stenotic lesions after extracranial-intracranial (EC-IC) bypass are well known; therefore, we would recommend CEA when the unilateral stenosis of the carotid artery appears to be more severe than the ipsilateral intracranial stenosis. In cases with unilateral carotid bifurcation stenosis and contralateral internal carotid artery occlusion or siphon stenosis, CEA is highly effective in patients with symptoms resulting from carotid bifurcation stenosis. Patients with symptoms referable to the side of the occluded internal carotid artery or siphon stenosis with poor collateral pathways may benefit from EC-IC bypass. CEA following EC-IC bypass may also be indicated for the contralateral asymptomatic carotid bifurcation ulcerative lesion.
