Imaging ultrasound in the intraoperative diagnosis of vascular defects.

High-resolution real-time ultrasonography was employed during 267 vascular operations in order to diagnose vascular defects such as intimal flaps, strictures, and thrombi. These defects occur at operative areas (e.g., anastomoses, endarterectomized segments, and sites of placement of occlusive clamps) and can lead to serious thrombotic complications in the early post-operative period. Ultrasound detected vascular defects in 83 patients (31.1 per cent). The defects in 59 patients were considered clinically insignificant because of their sizes and locations, and were not re-explored. Early post-operative results of these patients were comparable to those of the patients without demonstrated defects. In 24 patients (9.0 per cent of all patients examined), ultrasonography revealed clinically significant defects which prompted re-exploration. In 20 of these 24 patients, these vascular defects were confirmed and corrected. No defect was found at re-exploration in four patients, but two of them developed early postoperative thrombosis. Ultrasonography and arteriography were compared at 100 operative sites. The two imaging methods were equal in terms of sensitivity, specificity, efficiency, and predictability of a negative test. Predictability of a positive test was 77.8 per cent for ultrasonography and 59.1 per cent for arteriography. This indicates that fewer needless re-explorations would occur following a decision based on ultrasonography. Operative ultrasonography is a simple, safe and accurate technique that should be applied to reconstructive vascular surgery for diagnosis of vascular defects.