To study the results of eversion endarteterctomy of the external carotid artery (ECA) performed as part of standard CEA at a tertiary referral center using duplex ultrasonography.Sixty patients (18 women and 42 men) who underwent 65 carotid endarterectomies at Waikato Hospital between January 2006 and July 2007 for significant internal carotid artery (ICA) disease were studied. The procedure also included eversion endarterectomy of the ECA with sharp transection at eversion end point. Preoperative and postoperative duplex scans were performed for all patients using Acuson (USA) ultrasound machine and by one sonographer. Postoperative follow-up scans at periods between 6 weeks and 18 months were reviewed and analyzed with Ascer et al. Doppler ultrasound-scan peak systolic velocity (PSV) criteria.Preoperative scans revealed significant bifurcation disease involving both ICA and ECA in all patients. The first post operative scan, done six weeks post-operatively, revealed one incomplete ECA endarterectomy, resulting in moderate (50%-74%) stenosis, while the rest had no evidence of residual ECA disease at the site of ECA endarterectomy. Over the post-operative period, sixteen (24.6%) ECA lesions and no occlusions were reported. The degree of ECA stenosis ranged from moderate to severe with PSVs ranging from 120 to 461 cm per second. All ECA lesions were ostial. Only 3 (18.7%) lesions were detected in the first nine months post operatively. Fifteen lesions were smooth and regular on duplex, while one had features of irregular residual stenosis. Eight (50%) were isolated ECA lesions, while the rest was associated with either ICA restenosis or occlusion.ECA disease progression detected by Duplex ultrasound following eversion endarterectomy, as a part of CEA, commonly happens after 9 months and results in recurrent ECA stenosis, in most cases. Timing and features of the lesions suggest an intimal reaction as the aetiology in most cases. Eversion endarterectomy of the ECA does not predispose to ECA occlusion.