Classification of incidental findings in polytrauma computed tomography

Whole-body computed tomography (WBCT) is the standard procedure for examining severely injured patients. In addition to trauma-caused pathologies, a high number of non-trauma-related pathologies, incidental findings (IFs) are found regularly but often underestimated in WBCT. A standardized image analysis and a classification of IFs regarding their clinical graduation is of paramount interest for both treatment concepts and outcomes. The present study is aimed at developing and validating a feasible classification system. We evaluated WBCT scans regarding IFs and classified the IFs into 5 degrees of severity.

The present retrospective study included 1475 polytrauma patients from two maximum care hospitals who underwent a WBCT scan. Medical reports and CT scans were then reviewed for IFs.

The 83.8% of patients had suffered trauma-related injuries, and in 83.9%, IFs were found. The patients' age and gender significantly influenced the number and severity of IFs. Older and female patients tended to have more IFs. IFs are not described more often in patients without trauma-related findings (15%) than in patients with traumatic injuries (6%). Based on an analysis of 476 literature sources, we classified 511 different IFs into 5 categories. Most of them fell into categories 1 (variant) and 2 (benign), but 24% fell into categories 3 (follow-up), 4 (needs clarification), and 5 (needs treatment), requiring monitoring, clarification, or immediate treatment.

Due to the high rate of IFs, standardized image analysis and IFs classification are of utmost importance for both the patients' further treatment and the healthcare system's refinancing of resources.

IFs in polytrauma CT scans are common and, if not adequately addressed, can negatively impact patient outcomes-therefore, this 5-level classification standardizes interpretation and provides specific recommendations for further action, evaluation, or treatment.

In polytrauma, IFs are as common as trauma-related findings. There is a need for standardized classification. For IFs in WBCT scans, we propose a classification into 5 categories, labeled as IF-RADS 1-5.