INTRAOPERATIVE DUPLEX SCANNING REDUCES BOTH RESIDUAL STENOSIS AND POSTOPERATIVE MORBIDITY OF CAROTID ENDARTERECTOMY

To evaluate the effect of intraoperative duplex scanning (IDS) on the incidence of perioperative and postoperative strokes as well as residu al and recurrent stenosis, we reviewed 141 patients who underwent 152 consecutive carotid endarterectomies (CEAs) between July, 1990 and Jun e, 1995. Follow-up of 129 cases, with a mean follow-up of two years, r evealed no perioperative deaths and three strokes for a combined perio perative stroke-death rate of 2.3 per cent. In 50% (64 of 129) of the CEAs, intraoperative duplex scans were obtained based on the attending surgeon's preference. We noted that the incidence of residual stenosi s (> 50% stenosis on the first duplex after CEA) was significantly low er in those undergoing IDS (3/64) versus those without IDS (13/65) (P < 0.05; risk ratio 0.31; 95% confidence interval 0.11, 0.91). IDS resu lted in a modification of the internal carotid reconstruction in 9 per cent (6 of 64) of the cases with no resulting postoperative strokes o r residual/recurrent stenosis. There was no significant difference in the frequency of recurrent stenosis (> 50% stenosis after a normal dup lex) in the two groups (3 of 64 with vs 2 of 65 without). Of patients not undergoing intraoperative scanning, four underwent redo CEA for sy mptomatic residual stenosis due to a retained intimal flap in the inte rnal carotid artery. There were three strokes observed within 30 days of the initial CEA, all of which occurred in patients who did not unde rgo IDS at their initial operation. We conclude that IDS can identify technical defects following internal carotid reconstruction, thereby r educing the incidence of both residual stenosis and postoperative morb idity in patients undergoing CEA.