Value of contrast-enhanced arterial phase imaging in addition to portovenous phase in CT evaluation of blunt abdominopelvic trauma.

OBJECTIVES: Compare the diagnostic performance of the arterial phase plus portovenous phases (AP + PVP) of abdominopelvic CT (CT) with PVP alone in the detection and characterization of traumatic vascular injury and the effects on radiologists' confidence. METHODS: CT of 103 consecutive inpatients (median 36 years, 83 males) with blunt abdominopelvic injuries were retrospectively included if performed within 24 h after trauma and before definitive management. Images were re-reviewed by two blinded radiologists with disagreements resolved by the third radiologist. RESULTS: Sixty vascular injuries (liver 23, spleen 15, kidneys 9, pancreas 2, adrenals 3, mesentery, and pelvis 4 each) were found with 4 injuries (liver 2, spleen, and kidneys 1 each) not detected at initial CT. Nineteen (liver 6, spleen 10, kidneys 2, adrenal 1) were visualized only on AP. The sensitivity and accuracy of AP + PVP were 89.58-91.67% and 94.44-95.15%, compared to 61.67-62.50% and 77.67-80.00% of PVP alone. The agreements on the types of injury with final diagnoses were higher for AP + PVP than for PVP alone (78.69% vs. 44.26%). The mean diagnostic radiologist confidence ((1 = 25%, 2 = 50%, 3 = 75%, 4 > 90%) increased significantly in the detection (from 3.38 to 3.71) and characterization (from 2.46 to 3.67) of vascular injuries with AP + PVP compared to PVP alone. For 19 lesions detected only on AP, 11 (spleen 8, liver 2, adrenal 1) received nonoperative management; others had transarterial embolization or surgery. CONCLUSIONS: The addition of AP improves the detection and characterization of vascular injuries in CT evaluation of blunt abdominopelvic trauma. KEY POINTS: • AP+PVP was more sensitive and precise than PVP alone in the detection of traumatic vascular abdominopelvic injuries. • AP+PVP improved the characterization of traumatic abdominopelvic vascular injuries. • When all abdominopelvic vascular injuries were considered, AP increased radiologists' diagnostic confidence in the detection and characterization of vascular injuries.