Delayed manifestations of abdominal trauma: follow-up abdominopelvic CT in posttraumatic patients

Purpose Our study aims to investigate the frequency and patterns of delayed manifestations of abdominal and pelvic injuries which may not be identified or which fail to manifest on the initial abdominopelvic CT in posttraumatic patients. Methods For our institutional review board (IRB)-approved retrospective study, our hospital trauma registry was queried for patients with blunt multitrauma and Injury Severity Score (ISS) ≥ 16 between January 2010 and August 2016, yielding 3735 patients. A total of 203 patients received a follow-up abdominopelvic CT within six months from the initial scan and those with new findings on follow-up CT were identified. A retrospective blinded review of the initial CT examinations was performed by two experienced radiologists. The retrospective readings and original reports were compared to categorize the new abnormalities detected on follow-up CT scans. The categories included missed injuries, late presentations and sequelae of trauma, and complications of surgery, hospital admission, and invasive procedures. The patients’ notes were reviewed for the clinical indications, time interval for repeat CT examination, and subsequent clinical management. The software used for statistical analysis of the extracted data was Microsoft Excel for Mac (version 15.33). Results Out of 3735 patients, 203 patients received 232 follow-up abdominopelvic CTs. The average elapsed time between the initial CT and the follow-up CT was 15 ± 27 days. Evaluation for an abdominal fluid collection was the most common clinical indication, accounting for 40% of the total number ( n = 243) of indications. Delayed manifestations and complications of trauma were present in 41 patients due to 47 abnormalities, most commonly related to solid organ injury, followed by abdominal collections and hematoma. Twenty-nine CT findings (62%) were only detectable on follow-up CT, while nine injuries (19%) were missed on initial CT. The findings on repeated CT warranted eight surgical and 15 interventional procedures. Conclusion A small percentage of traumatic injuries may be unidentified or fail to manifest on the initial CT, resulting in delayed manifestations of abdominopelvic trauma, which may lead to subsequent readmission, delayed management, and more severe medical complications.