OBJECTIVE. The purpose of this study was to retrospectively evaluate appropriate and inappropriate application of nodule management guidelines in radiology reports of pulmonary nodules seen at CT.

MATERIALS AND METHODS. The CT reports of 181 patients examined in July and August 2007 (94 males, 87 females; age range, 2–88 years; mean, 60.3 ± 13.0 years) and 177 patients examined in March 2009 (106 men, 71 women; age range, 24–91 years; mean, 60.7 ± 14.0 years) were retrospectively reviewed to assess whether nodule management guidelines were inappropriately applied. The exclusion criteria for the 2007 cases included multiple nodules, stable nodules, potential metastatic disease, probable infectious or inflammatory cause, and age younger than 35 years. The exclusion criteria for the 2009 cases were all of the 2007 criteria except multiple nodules.

RESULTS. Guidelines were inappropriately applied 105 times in 2007 and 25 times in 2009. Reasons for inappropriate use in 2007 were multiple nodules in 70 of the 105 cases (67%), potential metastatic disease in 25 cases (24%), age younger than 35 years in four cases (4%), stable nodules in two cases (2%), probable infectious or inflammatory cause in two cases (2%), and protocol not included despite absence of exclusion criteria in two cases (2%). The reasons in 2009 were potential metastatic disease in 15 of the 25 cases (60%), age younger than 35 years in four cases (16%), stable nodules in three cases (12%), probable infectious or inflammatory cause in one case (4%), and protocol not included despite absence of exclusion criteria in two cases (8%). The percentage of cases with at least one error was 48.1% in 2007, significantly higher than the 13.6% in 2009 (p < 0.001).

CONCLUSION. Inappropriate application of guidelines for management of pulmonary nodules seen at CT was significantly reduced by removing multiple nodules from the exclusion criteria. Otherwise, causes for inappropriate application remained stable.