To perform a frequency analysis of the extracolonic findings (ECF) of the CT colonography between symptomatic and asymptomatic patients.

Seventy-two consecutive symptomatic patients and sixty-three consecutive asymptomatic patients who underwent CT colonography were enrolled in this study. Non-contrast enhanced axial images were reviewed retrospectively to identify the ECF and classified them as major, moderate or minor important findings according to their potential clinical importance. The frequencies of each classification and ECF were analyzed and compared between two groups (symptomatic and asymptomatic).

Eighty-two ECF were identified in 49 (68.1%) of the 72 symptomatic patients. The findings were classified as follows: major (8/49, 11.1%), moderate (17/49, 23.6%), minor (39/49, 54.2%). Sixty ECF were detected in 38 (60.3%) of the 63 asymptomatic patients. The findings were classified as follows: major (2/38, 3.2%), moderate (7/38, 11.1%), minor finding (35/63, 55.6%). No statistically significant differences were found between the two groups (p > 0.05) for the overall ECF frequency. However, a significantly higher frequency of major or moderate ECF was observed in symptomatic patients (30.6%) compared to asymptomatic patients (12.7%) (p < 0.05).

The overall ECF frequency was similar between symptomatic and asymptomatic patients; however, the frequency of clinically important ECF (major or moderate) was higher in symptomatic patients, compared to asymptomatic patients. This result suggests that the major or moderate ECF required a further work up or treatment in symptomatic patients.