Silent cerebral ischemia detected with diffusion-weighted imaging in patients treated with protected and unprotected carotid artery stenting

Background and Purpose - Percutaneous transluminal angioplasty with stent ( CAS) is an alternative method to endarterectomy in the revascularization of carotid artery stenosis. Protected CAS is currently used to prevent distal embolization. Diffusion-weighted MRI (DWI) is the most sensitive tool to evaluate silent cerebral ischemia. The purpose of this research was to assess the incidence of cerebral embolic lesions during CAS and to evaluate whether cerebral protection devices can reduce the number of silent cerebral ischemia with respect to unprotected CAS. Methods - Fifty-two patients with high-grade internal stenosis underwent CAS; 30 patients (group a) were treated with a cerebral protection device, and 22 (group b) were treated without it. All of the patients were evaluated preoperatively and postoperatively with fluid-attenuated inversion recovery and DWI sequences to depict the number of new embolic silent cerebral lesions. Results - Embolic silent cerebral lesions occurred in 30% of CAS. Cerebral protection devices reduce the number of new lesions significantly reducing the consistent lesions ipsilateral to the treated vessel. Inconsistent lesions do not differ in both groups of patients. Clinical, radiological, and procedural variables do not correlate with the appearance of new cerebral lesions. Conclusions - Embolic cerebral lesions detected with DWI are more frequent with unprotected CAS, although they are present also with the use of cerebral protection devices. Probably a part of silent cerebral lesions arise from the procedural maneuver in the aortic arch.