Atypical aortic dissection showed crescent or annular low density with thickening wall, usually with penetrating ulcer or calcification ingression.

• 结果 :主动脉不典型夹层为主动脉壁新月形或环形的低密度血肿包绕 ,常可见穿透性溃疡或钙化内移等征象 ;