Colour Doppler diagnosis of perigraft flow following endovascular repair of abdominal aortic aneurysm

Background. Endovascular repair of abdominal aortic aneurysm is a relativel y new surgical technique which is less invasive than conventional open abdo minal surgery but is associated with a significant specific complication of endoleak. The aim of this study was to determine the accuracy of duplex ul trasound imaging, utilising colour Doppler, as the primary method for post surgical monitoring of endovascular aneurysm repair. Methods. Experimental design: a case cohort study of 45 patients undergoing endovascular repair of abdominal aortic aneurysm. Setting: angiography, CT scanning and surgery performed at Westmead Hospital, a teaching hospital o f the University of Sydney; patients followed postoperatively at the Westme ad Vascular Laboratory a dedicated vascular diagnostic ultrasound facility. Patients: Forty males and five females, mean age 69.1 years (range 51 to 8 4). Interventions: patients underwent attempted insertion of an EVT (endova scular prosthesis) for exclusion of abdominal aortic aneurysm (mean diamete r 5.3 cm; range 4.0 to 8.4 cm). Conversion to open repair was required in t hree cases (6.6%). An aorto-biliac graft was inserted in 28 patients, a tub e graft in eight and an aorto-unilateral iliac graft with femorofemoral (or ilioilial) crossover graft in six. Measures: patients were followed over a period of 53 months (median follow-up time 15 months) with 106 colour Dopp ler scans of 39 endovascular grafts (mean of 2.9 scans per patient). Results. All aneurysms decreased in diameter (range 0.1 cm to 4.3 cm, mean 0.9 cm). Abnormal flow in the residual aneurysmal sac was found in three pa tients. In all three cases of endoleak the colour Doppler diagnosis was sup ported by CT scan and confirmed on angiography. The CT scans did not provid e any additional information to that obtained by colour Doppler imaging. Conclusions. Colour Doppler provides an effective means of non-invasive fol low-up assessment of patients who have had endovascular repair of abdominal aortic aneurysms.