Hachiya J, Nitatori T, Yoshino A, Okada M, Furuya Y
Department of Radiology, University of Kyorin School of Medicine, Tokyo, Japan.
J Comput Assist Tomogr. 1993 May-Jun;17(3):374-8. doi: 10.1097/00004728-199305000-00006.
Calcification along the outermost aspect of the aorta usually means atherosclerotic aneurysm. On occasion, however, this peripheral type calcification is seen in chronic aortic dissection and leads to a misdiagnosis. Conventional chest roentgenography and CT of 50 cases of chronic dissection proven by angiography were reviewed. Four of these cases (8%) showed calcification in the outermost wall of the affected portion of the aorta. Two cases were Stanford type A and the other two cases were type B. In type A cases chest roentgenography showed calcification in the wall of the dilated ascending aorta closely mimicking aneurysm. In type B cases, calcification was in the outer wall of a localized hump in the descending aorta. Computed tomography clearly demonstrated that this peripheral calcification was located in the outermost wall of the false lumen. Review of the pathologic literature shows sporadic reports of such phenomenon and a theory of endothelialization of the false lumen. It is presumed that the endothelialized false lumen may develop atheromatous changes much more rapidly than the true lumen since two of four cases showed calcification only in the wall of the false lumen with the intimal flap and the wall of the true lumen remaining noncalcified.
主动脉最外层的钙化通常意味着动脉粥样硬化性动脉瘤。然而，偶尔这种外周型钙化也可见于慢性主动脉夹层，从而导致误诊。回顾了经血管造影证实的50例慢性夹层的传统胸部X线片和CT表现。其中4例（8%）在主动脉受累部位的最外层壁出现钙化。2例为斯坦福A型，另外2例为B型。在A型病例中，胸部X线片显示扩张的升主动脉壁钙化，酷似动脉瘤。在B型病例中，钙化位于降主动脉局部隆起的外壁。计算机断层扫描清楚地显示这种外周钙化位于假腔的最外层壁。回顾病理文献发现有关于这种现象的零星报道以及假腔内皮化的理论。据推测，内皮化的假腔可能比真腔更快地发生动脉粥样硬化改变，因为4例中有2例仅在假腔壁出现钙化，而内膜瓣和真腔壁未钙化。
