Value in the Diagnosis of Multi-slice Spiral CT Angiography in Atypical Aortic Dissection

Objective To investigate the multi-slice spiral CT(MSCT) angiography In the diagnosis of Atypical Aortic Dissection(AAD).Methods 12 cases suspected of Atypical Aortic Dissection were examined by MSCT.To combine two-dimension and three dimensional image reconstruction technique.Then executing image was analyzed.Results 8 Debakey type A cases,4 type B cases of Atypical Aortic Dissection were found in our experiments,ADD CT showed that(1) AAD had no split intimal flap and double channels;(2) The aortic wall was crescentic or circumferential incrassation(false lumen) to 5.0～30 mm;(3)On unenhanced CT scan,the density of false lumen was higher or isodensity or lower than that of true lumen respectively in 6 cases,4 cases and 2 cases;(4) The false lumen had on-enhancment on postcontrast CT scan;(5)10 cases(83 %) were lack of serious depression in the involved aortic lumen;(6) Some changes were shown in atypical false lumen with follow up CT scan.Two dimensional imaging(MPVR and CPR) could clearly showed the extent,size and details of lesions.The space relationship and calcifation of aorta were displayed in three dimensional imaging(SSD,VR and MIP).The presence of intimal flap and reentry of dissection could be clarified by CTVE.Conclusion Associated with image post processing,MSCT angiography might be an effective method for diagnosing Atypical aortic dissection.