Aortic dissection: computed tomography characterization of the true and false lumen in acute and chronic stages

Aortic dissection is a longitudinal rupture of the aorta associated with the destruction of the middle layer of the aortic wall, the separation of intima and adventitia and the formation of two lumens, which is an urgent condition requiring emergency surgical care. The presented illustrated literature review is devoted to the differentiation of true and false lumens in the acute and chronic stages of aortic dissection during computed tomography.

The article summarizes and systematizes the experience of computed tomography diagnostics in aortic dissection based on data available in domestic and foreign publications, as well as the results of their own clinical observations. We have identified the main and secondary signs detected by computed tomography in cases of aortic dissection.

The most important and unambiguously indicative of false lumen in classical acute and chronic aortic dissection are the larger size of the false lumen, the sign of a “beak” and the sign of a “web”. Other signs, such as calcification of the aorta, changes in the curvature and thickness of the intimal medial flap, the “Mercedes-Benz” symptom, the presence of thrombotic masses, the characteristics of the interposition of the lumens and the “wind indicator” symptom are less constant, however, a careful analysis of the totality of all secondary signs allows you to give important diagnostic information and characterize as fully as possible the manifestations significant for a cardiovascular surgeon dissections of the aorta.

A cumulative analysis of computed tomographic signs in cases of aortic dissection will help a practicing radiologist not only distinguish the true lumen from the false aorta, but also determine the stage of the process based on their characteristics, which affects the tactics of complex treatment, especially with atypical dissection.