Radiologists' Recommendations for Additional Imaging on Inpatient CT Studies: Do Referring Physicians Follow Them?

Studies have found that recommendations for additional imaging (RAI) accompany up to 31% of index computed tomography (CT) scans. In this study we assessed the frequency with which recommendations are accepted by the referring physician and the impact of AI on case management.

We performed a cross-sectional study of all index CT scans of the chest, abdomen, and pelvis performed on adult inpatients during a 1-month period at a tertiary medical center. Each radiology report was examined for mention of RAI. We used a standardized abstraction tool to review medical records for the indication for the RAI (related to original diagnosis vs incidental finding), the clinician's rationale for pursuing or discarding the RAI, and the impact of the AI on the inpatient treatment plan.

Among the 430 scans reviewed, most (57.7%) were of the abdomen/pelvis. RAI was recommended in 67 cases (odds ratio [OR] 15.6%; 95% confidence interval [CI] 12.4-19.3) and AI was completed in 24 of 67 cases (35.8%). Factors associated with a recommendation for AI were the presence of an incidental finding (OR 3.5, 95% CI 1.7-6.8) and verbal communication of the result to the ordering provider (OR 2.09, 95% CI 1.23-3.5). When performed, AI altered the treatment plan 75% (18/24) of the time. Among the 43 cases in which AI was not performed, 34.1% were deferred to outpatient, 13.6% underwent alternative clinical intervention, and 13.6% were judged unnecessary by the primary team. No rationale was documented in the chart for the remaining 38.6%.

Despite concerns about autoreferral by radiologists for AI studies, we found a lower rate than in many prior studies, which may reflect a change in clinical practice. One-third of these recommendations were implemented and verbal communication was strongly associated with the likelihood of second image ordering. In the majority of the cases, the AI affected patient management. Based on these findings, radiologists should consider calling the ordering provider to increase the likelihood that the primary team will follow their recommendations.