Incidental findings were common among patients undergoing whole-body computed tomography for traumatic injuries in the emergency department, with a meta-analysis estimating that 29.8% had findings requiring some form of intervention.
In the systematic review and meta-analysis, researchers evaluated 22 studies including 18,538 patients who underwent computed tomography (CT) following traumatic injury. Nine studies assessed whole-body CT, and 13 assessed selective CT of specific body regions. Most studies were retrospective and conducted in high-income countries.
For whole-body CT, incidental findings requiring any intervention included findings that prompted clinical follow-up, diagnostic workup, or treatment. The estimate carried very low certainty because of methodological limitations, nonstandardized classification of incidental findings, and substantial variation among studies; individual study estimates ranged from 15.7% to 58.7%.
Findings requiring urgent intervention were less common but not rare, occurring in an estimated 7.6% of patients undergoing whole-body CT, with low certainty. The analysis also estimated that incidental findings led to pathologically confirmed cancers in 0.6% of patients and emergent nontraumatic vascular pathologies in 0.3%, both with moderate certainty.
Most clinically relevant incidental findings were detected in the chest, abdomen, or pelvis. Detection rates were generally lower when CT was limited to narrower body regions, although data for the head, neck, and spine were sparse and not suitable for pooled multivariate analysis.
The cancer and vascular estimates should be interpreted cautiously. Follow-up and implementation of recommended interventions were inconsistent across studies, which may have underestimated downstream diagnoses. In studies reporting implementation, intervention rates ranged from 10.3% to 36% for findings requiring any intervention and from 27.8% to 100% for findings requiring urgent intervention, although the highest estimate was based on a very small sample.
The researchers noted that the 0.6% cancer detection estimate was similar in magnitude to detection rates from single-cycle CT colonography in average-risk screening populations, while the 0.3% vascular pathology estimate was within the range reported for screening ultrasound detection of abdominal aortic aneurysm requiring treatment.
However, the findings should not be interpreted as evidence that detecting incidental findings improves long-term outcomes. The review focused on prevalence and did not evaluate mortality, readmission, cancer-specific outcomes, aneurysm rupture, or other patient-centered outcomes. Only one included study reported a patient-level outcome, finding that patients with incidental findings had an average hospital stay 2 days longer than those without such findings.
“The widely reported prevalence range suggests variations in radiologist recommendations and reporting in clinical practice,” wrote lead study author Kyohei Nagasawa, of Fujita Health University School of Medicine, and colleagues.
The researchers called for standardized classification and reporting systems, along with longer follow-up, to better define the clinical implications of incidental findings on trauma CT.
Disclosures: The researchers reported no competing interests. The study was supported by Japan’s Ministry of Education, Culture, Sports, Science and Technology. The funder had no role in the study design, data collection, analysis, interpretation, or writing.
Source: BMJ Open