The Application Of Aortic Angiography With 64 Multi-Slices On Aortic Dissection

Objective To investigate the application of 64 multi-detector CT with bolus tracking on aortic dissection. To determine the value of MPR CPR VR SSD MIP in detecting of tear entry, the extent of intimal flap, and the true and false channel of dissection. Materials and Methods Thirty-nine patients with suspected aortic diseases were evaluated in this study with Siemens 64 multi-slices CT scanner. All of the scans were performed with the bolus tracking of 100 ml nonionic contrast material followed by flushing 40-50 ml of physiologic saline solution at 3.5-4ml/sec. Average value of aorta enhancement and its standard deviation over baseline were calculated for both group, with dissection and non-dissection. The imaging quality in both groups were graded as excellent , good, poor and failure and were compared respectively. MPR CPR VR SSD MIP were reconstructed from raw data in all patients. The demonstration rate of each reconstruction on tear entry, the extent of intimal flap, and the true and false channel of dissection was calculated, as well as the sensitivity , specificity, and accuracy of each reconstruction for entry tear. Results The mean value of aorta enhancement for non-dissection group was not significantly different from that in true channel of dissection group (P>0. 05), but significantly different from that in false channel of dissection group (P=0.01) . In dissection group, the mean value of aorta enhancement in true channel differed significantly from that of false channel(P=0.01). The imaging quality of both groups was not significant different (P>0. 05). The demonstration rate of MPR, CPR, VR, and SSD on tear entry was 80.9%, 85.7%, 19%, and 9.5%, respectively. And for intimal flap was 100% respectively. MIP didn't demonstrate the tear entry and intimal flap. The demonstration rate of MPR, CPR, VR, and SSD on the true and false channel was 100% respectively, and MIP was 76.2%. Conclusion 64 multi-slices CT angiography with bolus tracking can well display the aortic dissection and the row data was suitable for 3D postprocessing. MPR, CPR, VR, SSD, and MIP are useful in evaluating aortic dissection. MPR and CPR are superior to MIP.