Cerebral microembolism and ischemic changes associated with carotid endarterectomy

Purpose: The purpose of this study is to characterize microembolic signals (MS) that occur during the various phases of carotid endarterectomy (CEA) and to consider their relationship to postoperative changes on magnetic resonance imaging (MRI). Methods: This was a retrospective study of 76 patients who underwent 78 carotid endarterectomies at a referral center. Perioperative transcranial Doppler monitoring and MRT were performed before and after CEA. The types of MS that occurred during phases of surgery were analyzed and compared with MRI changes. Results: We observed a clinical stroke in one patient (1.3%) and ipsilateral small areas of silent ischemic change on seven postoperative MRI studies (9.0%). In 95% of CEAs, MS were detected. Only those MS observed in the recovery room that occurred at a rate of more than five per 15 minutes were associated with postoperative MRI ischemic changes (p < 0.0001). Conclusions: Ischemic changes on MRI after CEA are related to postoperative MS.