[Spiral computed tomography in evaluation of arteriovenous fistula for hemodialysis. Preliminary report]

Abstract

Failure of arteriovenous fistula (AVFf) still remains the "Achilles'heel" of chronic haemodialysis (HD) programme. Therefore, early, potentially non-invasive diagnosis and prompt surgical correction of AVFf are needed. For these purposes spiral computed tomographic angiography (SCTA) was used for evaluation of clinically suspected AVFf in 19 patients (10M/9F, aged 58.6 +/- 14.6 years, on HD for 34.4 +/- 29.3 months). SCTA was performed using Marconi MX8000 scanner covering whole AVF. After intravenous administration to the peripheral vein of the other leg of 100 ml of non-ionic lomeron 350 contrast (3 ml/s), axial CT images were obtained helically covering whole surface of AVF. Time delay was measured by Trigger function. Maximum Intensity Projections (MIP), 4D-Angio and virtual endoscopy (VE) techniques were used for reconstruction. MIP images demonstrated contrast-enhanced vascular structures and other high-density tissues (calcifications). VE enabled non-invasive simulation of endoscopic procedures and interactive intravascular navigation. Total number of 24 SCTA were performed. We found normal patency of AVF in 5 patients. In the remaining 14 subjects, the following abnormalities were found: stenosis of AVF at the site of anastomosis or in distal segment of efferent vein in 6 SCTA examinations, dilatation in 7 SCTA, acute or chronic thrombosis of AVF in 9 SCTA procedures including total occlusion of AVF in 2 cases. In 2 cases pseudoaneurysms of AVF were found. In 7 SCTA examinations more than one reason of AVFf was found. Photographs of every AVF complication are presented. We noted only one complication of SCTA-rupture of venous vessel on the opposite arm during contrast injection. There were no hypersensitivity reactions to the contrast.