Objectives: to test whether the occurrence of microembolism differed between eversion and standard carotid endarterectomy (CEA).
Design: prospective, non-randomised transcranial Doppler (TCD) monitoring study 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%) patients had a shunt inserted based on continuous EEG monitoring. Continuous middle cerebral artery TCD monitoring (EME, TC-4040) was performed intraoperatively and for 45 min postoperatively on day 1, day 2-3, day 4-5 and after 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 patients 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 postoperatively in four (15%) and 16 (48%) patients having eversion and standard CEA, respectively (p< 0.02). Four patients developed new neurological symptoms equally distributed between eversion and standard CEA. Two (3%) deficits were permanent and two transient. The patency of the carotid bifurcation was confirmed in all instances with duplex scanning.
Conclusion: we identified a surprisingly high number of postoperative embolic events as detected with transcranial Doppler in patients who had undergone carotid surgery using standard endarterectomy, as compared to patients who underwent eversion endarterectomy. Whether this difference has any clinical implication has yet to be proved.
Copyright 2000 Harcourt Publishers Ltd.