Changes in Renal Artery Movement Due to Respiration Before and After Fenestrated Endovascular Repair

The investigators would like to evaluate the location within the renal artery of maximal angular displacement before and after fenestrated endovascular aortic repair (FEVAR) using CT with end-inspiration and end-expiration CT images before and after repair. The investigators would then locate the renal artery segment with maximal angular displacement on each and describe any changes. Because these patients would be getting pre and post-surgical CTs as part of standard of care, there would be no added charge to obtain the information for the study. There would be, however, minimal increased radiation exposure resulting from the extra scan being performed during end-expiration and the patients would have to consent to the slight added risk to participate.