Objective To analyze the features of dynamic contrast-enhanced CT of blunt hepatic injury in rabbits. Methods The model of blunt hepatic injury was established in 40 New Zealand white rabbits with a steel ball falling down to the xiphoid process of the animals. Plain CT scan and dynamic contrast-enhanced CT scan (Hispeed spiral CT/2i, GE, America) of the liver were performed. Arterial,portal and balanced phases were respectively at 8-10 s, 35-40 s and 120-150 s after initiation of the contrast medium injection. The non-enhanced and enhanced images were compared in aspects of location and range of injury, tear of the liver capsule, active bleeding, involvement of the main hepatic veins and CT features of abdominal hemorrhage, which was further compared with the results of gross anatomy. Results The rate of plain CT scan was obviously lower than that of dynamic contrast-enhanced CT scan,which defined single tear in 13 patients, multiple lacerations in 18, liver subcapsular hematoma in seven,liver hematoma in nine, liver coated gap in 17, active bleeding in nine and main hepatic vein injury in five, with coincidence rates with the results of gross observation for 13/13,18/18,7/9,9/9,25/30,9/5and 5/4 respectively. According to Moore' s classification, CT/Laparotomy performed from grade Ⅰ to grade Ⅵ were 5/4 patients at grade Ⅰ , 15/13 at grade Ⅱ, 9/11 at grade, 5/6 at grade Ⅳ, 1/2 at grade Ⅴ, O at grade respectively. Conclusion Dynamic contrast-enhanced CT scan, especially at portal and balanced phases, is of great value for diagnoses of liver injuries and determination of injury severity. Key words: Liver; Wounds,nonpenetrating; Rabbits; Dynamic contrast-enhanced; Tomography,X-ray computed
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