POSTOPERATIVE COLOR-FLOW DUPLEX SCANNING IN AORTIC ENDOGRAFTING

Purpose: To report the feasibility and sensitivity of duplex sonograph y compared to computed tomography (CT) for aortic endograft follow-up surveillance. Methods: In a 26-month period, 113 aortic aneurysm patie nts received 79 tube and 34 bifurcated stent-grafts. Follow-up used co ntrast-enhanced CT scanning and duplex sonography with an intravenous ultrasound contrast agent (Levovist). Results: Eleven patients (9.7%) were converted to open repair; 1 died from hemorrhagic shock secondary to retroperitoneal hematoma. The mean follow-up time was 7.2 months ( range 1 to 24), during which 5 patients died of unrelated causes. Sixt een primary (within 30 days) and 5 secondary endoleaks were detected b y duplex after tube graft implantation. Among 5 endoleaks due to retro grade side-branch perfusion, 3 were detected only with contrast-enhanc ed duplex scanning. Iliac artery occlusion was also documented using d uplex; however, 2 stent fractures could not be seen with ultrasound. T en primary endoleaks were detected in bifurcated stent-graft patients. One endoleak originating from the distal iliac limb anchoring site wa s missed by duplex owing to bowel gas. Graft limb thrombosis was clear ly identified by lack of a flow signal on duplex. Conclusions: Duplex sonography could be a valuable, reliable, and economical surveillance tool for endovascular aortic reconstructions. The adjunctive use of an intravenous ultrasound contrast agent increased the sensitivity for d etecting endoleak to a level comparable to contrast-enhanced CT scanni ng. However, stent fractures may not be seen on ultrasound, and bowel gas can interfere with obtaining an adequate image.