Eversion carotid endarterectomy generates fewer microemboli than standard carotid endarterectomy

Objectives: to test whether the occurrence of microembolism differed betwee n eversion and standard carotid endarterectomy (CEA). Design: prospective, non-randomised transcranial Doppler(TCD) monitoring st udy of 61 patients. Materials and methods: eversion CEA was performed in 27 and standard CEA in 34 patients. Surgery was performed under general anaesthesia. Three (5%) p atients had a shunt inserted based on continuous EEG monitoring. Continuous middle cerebral artery TCD monitoring (EME, TC-4040) was performed intraop eratively and for 45 min postoperatively on day 1, day 2-3, day 4-5 and aft er 3 months. Unidirectional signals lasting >25 ms, having intensities of > 9 dB were considered to represent embolic events. Results: intraoperative embolic events were detected in 50 (93%) of 54 pati ents in whom successful intraoperative TCD monitoring was achieved. Events occurred most frequently immediately following clamp release (85%), without difference between the two techniques. Embolic events were encountered pos toperatively in four (15%) and 16 (48%) patients having eversion and standa rd CEA, respectively (p < 0.02). Four patients developed new neurological s ymptoms equally distributed between eversion and standard CEA. Two (3%) def icits were permanent and two transient. The patency of the carotid bifurcat ion was confirmed in all instances with duplex scanning. Conclusion: we identified a surprisingly high number of postoperative embol ic events as detected with transcranial Doppler in patients who had undergo ne carotid surgery using standard endarterectomy, as compared to patients w ho underwent eversion endarterectomy. Whether this difference has any clini cal implication has yet to be proved.