Acta chir belg, 2007, 107, 151-154 Introduction Carotid angioplasty and stenting (CAS) has been intro- duced as a safe alternative to carotid endarterectomy (CEA) in patients with severe internal carotid artery stenosis. Nevertheless there is still concern regarding its safety in relation to the cerebral embolization during and after the procedure. Microembolic events during CAS are investigated by Transcranial Doppler (TCD) (1-4), diffusion–weighted MR imaging (DWI) (5-10) and neu- ropsychological test (NPT) (11-13). In this study we have correlated the prevalence and the clinical relevance of microemboli detected by TCD in 100 unselected patients submitted to CAS and CEA. Material and method One hundred consecutive patients with hemodynamic lesions of carotid artery (more than 70% stenosis, evalu- ated by ECST method) were submitted to 50 CEA and 50 CAS from January 2005 to January 2006 in our insti- tution. Sixty-four (64) patients were males and 36 females, with a mean age of 66 years (62-82 years) ; 54 of them were asymptomatic. Embolism to the Brain During Carotid Stenting and Surgery B. Gossetti*, R. Gattuso*, L. Irace*, F. Faccenna*, S. Venosi*, L. Bozzao**, M. Fiorelli**, R. Andreoli*, C. Gossetti*** Chair of Vascular Surgery*, Chair of Neuroradiology**, “La Sapienza” University of Rome, Italy ; UPS***, Università Pontificia Salesiana. Key words. Carotid stent ; transcranial Doppler ; carotid endarterectomy ; microembolic event ; magnetic resonance imaging. Abstract. The aim of this study was to assess the prevalence and clinical relevance of microembolism in one hundred unselected patients submitted to 50 carotid endarterectomy (CEA) and 50 carotid stenting (CAS) procedures from January 2005 to January 2006 for hemodynamic lesions of the carotid bifurcation (> 70% stenosis). Material and methods : High-resolution Colour-Flow Mapping (CFM), Transcranial Doppler (TCD), cerebral comput- ed tomography (CT) or magnetic resonance (MR) and four psychometric tests (Mini mental state, Beck depression inventory, Zung anxiety inventory, SF-12) were carried out in the preoperative evaluation in all the patients. In the CEAs loco-regional anesthesia (100%), patch angioplasty (84%) and Pruitt- Inahara shunt (4%) were employed ; in the CASs local anesthesia (100%), three different carotid stents (Precise-Cordis, Acculink-Guidant and Carotid Wallstent-Boston Scientific) and three temporary distal filter protection devices (Angioguard-Cordis, Accunet-Guidant, Filterwire-EZ- Boston Scientific), without pre-dilatation, were employed. TCD monitoring was used intra-operatively and 12 hours post-operatively to evaluate the presence and the number of microembolic events (ME’s) and to investigate the efficiency of neuroprotective filter devices. The efficacy of the in situ opened filter was judged evaluating the decrease of mean blood velocity in ipsilateral middle cerebral artery and the reduction rate of microembolic events (number of microemboli detected during the entire procedure/number of microemboli detected during the filter positioning). Diffusion-weighted magnetic resonance imaging (DWI) of the brain was obtained within 24 to 48 hours after the procedures to detect new ischemic brain lesions. Psychometric tests were repeated at the discharge of the patient and after two months to evaluate cognitive faculties. Results : During postoperative period (30 days) and follow-up, no procedure-related death and three regressive minor strokes occurred : 1 in CEA (2%) and 2 in CASs (4%) ; a cranial nerve lesion occurred in CEA (2%). TCD monitoring showed ME’s (a mean of five events) in 37 CEAs (74%) and in 50 CASs (100%) (a mean of 60 ME’s). In five patients submitted to CAS repeated microemboli occurred during one hour postoperative TCD control (10%). A 10-30% decrease of mean blood velocity basal value was recorded in the ipsilateral middle cerebral artery when the filter device was opened. A mean 70% reduction of ME’s was obtained with a cerebral protection system deployed. Postoperative DWI detected new focal ischemic lesions in 24 patients [22 after CAS (44%) (a mean of 5 new ipsi and contra-lateral lesions) , and 2 after CEA (4%). Cognitive capability worsened in 20 patients [18 after CAS (36%) e 2 after CEA (4%)]. Conclusions : Mortality and morbidity rates of patients submitted to CAS are comparable to the results obtained by CEA. A great number of ME’s are recorded by TCD during endovascular procedures, more than during open surgery. ME’s due to CAS are reduced by filter protection devices, but the cognitive faculties in a great number of “asympto- matic” patients are decreased after CAS.