Incidence and significance of nonaneurysmal-related computed tomography scan findings in patients undergoing endovascular aortic aneurysm repair

Abstract

This study examined the frequency and nature of incidental findings seen on computed tomography (CT) scans during preoperative and postoperative follow-up in patients undergoing endovascular aortic aneurysm repair (EVAR). Between January 1, 2000, and March 1, 2006, 176 consecutive patients who underwent EVAR at our institution were retrospectively reviewed. Patients were included in the study if all preoperative and postoperative surveillance CT scans were performed at our institution. Eighty-two patients, 26 women (32%) and 56 men (68%), met this criterion. Their mean age was 76 years (range, 51-103 years). Official CT scan reports were reviewed. Findings were considered primary incidental if they were noted on preoperative CT scans and secondary incidental if they appeared on surveillance CT scans but not on the preoperative study. Primary and secondary incidental findings were considered either benign (eg, gallstones, diverticulosis) or clinically significant if they warranted further workup (eg, suspicious masses or changes suggestive of malignancy, internal or diaphragmatic hernias, and diverticulitis). The median follow-up was 29 months (range, 3-60 months). Each incidental finding was counted only once, on the first scan in which it appeared. Of the 82 patients, 73 (89%) had at least one primary incidental finding, and 14 (19%) of these were clinically significant. Secondary incidental findings, many of which were clinically significant, continued to appear throughout the follow-up period. The most common clinically significant primary incidental finding was the presence of a lung mass (n = 4). The most common clinically significant secondary incidental findings were lung mass (n = 6), liver mass (n = 6), and pancreas mass (n = 3). There was a significant difference in the proportion of men to women in the group with clinically significant incidental findings vs the group without clinically significant incidental findings (P = .03959). Differences between the groups with respect to age or aneurysm size were not significant. CT scans yielded surprisingly large numbers of both primary and secondary incidental findings, many of which were clinically significant. Primary incidental findings were more common than secondary incidental findings; however, clinically significant findings were found at a consistent rate throughout the study period.