Background: Computed tomography (CT) has been used to assess patients following endovascular aneurysm repair to determine the need for secondary endoluminal or operative procedures. This prospective study compared CT and duplex imaging to evaluate aneurysm morphology following endoluminal aortic grafting.
Methods: Twenty patients were evaluated at regular intervals following successful endoluminal aneurysm repair. CT and duplex scanning were compared in their ability to determine aneurysm and aortic diameter, the presence of perigraft extravasation (endoleaks) and technical defects in the endograft.
Results: In 20 patients who were assessed 6 months after operation, duplex imaging identified four endoleaks (two early, two late; one proximal, three distal). In three cases, the aneurysm diameter progressively increased after operation. 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 increased following endografting.
Conclusion: Duplex imaging is a less invasive, less costly alternative to CT in the follow-up of patients after endoluminal aortic surgery. Increase in size of the aneurysm sac following endovascular aneurysm repair strongly suggests the presence of an endoleak.