After limited experience with eversion endarterectomy of the internal carotid artery, comparison has been made between perioperative results obtained with the eversion technique and with the conventional method. The perioperative results of 715 consecutive cases of patch plasty of the internal carotid artery performed between January 1986 and December 1990 were reviewed and compared with perioperative data of 739 consecutive cases of eversion endarterectomy, performed between January 1991 and December 1993. The duration of surgery was also recorded. Statistical analysis was carried out, using X
2 test, Fisher's Z test and Student's t-test. The postoperative stroke rate was 2.9% in the conventional endarterectomy group, and 0.95% in cases of eversion endarterectomy (P<0.01); the stroke mortality rates were 1.8% and 0.54% respectively (P<0.05). Overall mortality rate was 2.9% in the conventional group and 0.95% in the eversion group (P<0.01); combined morbidity and mortality rate was 4% versus 1.35% (P<0.001). A statistically significant difference was found in favour of the eversion method between the duration of surgery (90.9 min versus 52.8 min; P<0.005) and between the mean clamp time (34.9 min versus 22.4 min; P<0.005). On the basis of these results, it is concluded that eversion endarterectomy of the internal carotid artery is a safe and rapid technique and its immediate results were superior to those obtained after conventional endarterectomy and patch plasty.