A comparison of B-mode real-time imaging and arteriography in the intraoperative assessment of carotid endarterectomy.

In this study we compare intraoperative B-mode imaging with arteriography in the same patient for intraoperative assessment after carotid endarterectomy. Since April 1983, 158 patients have been studied with both techniques. After a routine intraoperative arteriogram, the vessel was examined in multiple planes with a B-mode imager, and the impression of the operating surgeon was recorded before review of the arteriogram. Thirteen studies were unsatisfactory because the design of the probe did not allow examination of the high carotid bifurcation. Twelve patients had significant abnormalities (8.3%) in the internal carotid artery. Results were false negative in three intraoperative arteriograms (2.1%) and five B-mode imaging studies (3.4%). In each of the 12 cases the vessel was reopened and the abnormality confirmed and corrected. Fifty-seven patients had abnormalities (37%) in the external carotid artery. Results were false negative in eight arteriograms (5.3%) and in 12 B-mode imaging studies (7.9%). Fourteen of the 57 patients with abnormalities of the external carotid artery underwent repeat operation to correct the technical problem. Although not conclusive, the incidence of postoperative neurologic deficit as well as that of recurrent carotid stenosis seems decreased since both modalities for intraoperative assessment were used. The data suggest that neither intraoperative angiography nor B-mode imaging, when used alone, accurately detects all postoperative abnormalities. The results also suggest that a heightened sensitivity to technical details may improve both early and late postoperative morbidity.