Cerebral ischemia after carotid intervention.

PURPOSE

To determine the incidence of symptomatic and asymptomatic cerebral ischemic lesions found on diffusion-weighted magnetic resonance imaging (DW-MRI) after carotid interventions.

METHODS

A prospective study was conducted to assess new cerebral ischemic lesions using DW-MRI in symptomatic patients with carotid artery disease undergoing protected carotid artery stenting (CAS) or carotid endarterectomy (CEA). DW-MRI was performed before and after the intervention in 44 patients (21 CAS and 23 CEA). Two experienced radiologists not involved in the carotid procedures or neurological assessment compared the postprocedural DW-MR images with those acquired before the intervention.

RESULTS

Three (6.8%) of the 44 patients suffered strokes: 1 major and 1 minor stroke after CEA and 1 minor stroke after CAS. DW-MRI showed 15 new hyperintense lesions in 2 (9%) of 23 CEA patients; 31 new hyperintense lesions were found in 9 (43%) of the 21 CAS patients. The majority of new lesions were located in the ipsilateral vascular territory; 2 CAS patients also showed 6 new hyperintense lesions in the cerebellum. The mean lesion load per patient was 2.52 cm(3) (range 0.31-4.74) in the CEA group and 1.74 cm(3) (0.03-9.72) in the CAS group (p=0.35). The volume of the individual lesions in CEA patients was 0.39 cm(3) (range 0.01-2.16) compared to 0.52 cm(3) (range 0.01-5.47) in the CAS group (p=0.23). Patients who were asymptomatic after the intervention had fewer lesions (p=0.03) and a smaller lesion load than symptomatic patients.

CONCLUSIONS

Ischemic lesions were more frequently seen on DW-MRI after carotid stenting than after endarterectomy. The majority of the detected lesions did not cause neurological deficits.