COMPARISON OF COMPUTED-TOMOGRAPHY AND DUPLEX IMAGING IN ASSESSING AORTIC MORPHOLOGY FOLLOWING ENDOVASCULAR ANEURYSM REPAIR

Background Computed tomography (CT) has been used to assess patients f ollowing endovascular aneurysm repair to determine the need for second ary endoluminal or operative procedures. This prospective study compar ed CT and duplex imaging to evaluate aneurysm morphology following end oluminal aortic grafting. Methods Twenty patients were evaluated at re gular intervals following successful endoluminal aneurysm repair. CT a nd duplex scanning were compared in their ability to determine aneurys m and aortic diameter, the presence of perigraft extravasation (endole aks) and technical defects in the endograft. Results In 20 patients wh o were assessed 6 months after operation, duplex imaging identified fo ur endoleaks (two early, two late; one proximal, three distal). In thr ee cases, the aneurysm diameter progressively increased after operatio n. In patients with a thrombosed aneurysm sac, the aneurysm regressed at a median of 0.40 (range 0.13-0.8) cm per year. The CT findings were similar (median regression 0.43 (range 0-1.0) cm per year), although CT was unable to predict the site of the leak as accurately as duplex imaging. CT demonstrated that the diameter of the juxtarenal aorta inc reased following endografting. Conclusion Duplex imaging is a less inv asive, less costly alternative to CT in the follow-up of patients afte r endoluminal aortic surgery. Increase in size of the aneurysm sac fol lowing endovascular aneurysm repair strongly suggests the presence of an endoleak.