Evaluation with Doppler vascular ultrasound in postoperative endovascular treatment of abdominal aortic aneurysm: a prospective comparative study with angiotomography

BACKGROUND: Diagnosis of abdominal aortic aneurysm (AAA) is usually incidental, and surgical treatment, when indicated, may be open or endovascular. The drawbacks of computed angiotomography (CTA) and the advantages of Doppler ultrasonography have led to the development of alternative follow-up protocols, comparing the two methods. OBJECTIVE: To determine validity indices for Doppler ultrasonography and to correlate them with CTA results in a group of patients who had undergone elective endovascular treatment of AAAs. MATERIAL AND METHODS: Thirty-three patients were selected. The following three items were evaluated: 1) presence or absence of endoleak; 2) presence of blood flow in the aortoiliac segment; and 3) maximum AAA diameter. RESULTS: For the detection of endoleak, Doppler ultrasonography showed a sensitivity of 54.5%, a specificity of 92.8%, a positive predictive value of 85.7%, a negative predictive value of 92.8%, and an overall accuracy of 76%. For the evaluation of blood flow in the aortoiliac segment, values were 100, 97.8, 80, 97.8, and 98%, respectively. Maximum AAA diameter was similarly measured by both methods, with statistically significant differences (mean difference: 1.98 mm). Pearson's correlation coefficient was 0.97, showing that Doppler ultrasonography and CTA yielded similar results. CONCLUSION: Doppler ultrasonography showed good validity indices and a moderate correlation with CTA in the postoperative evaluation of patients undergoing endovascular treatment of AAAs.