Intimointimal Intussusception in Acute Aortic Dissection

Intimointimal intussusception in aortic dissection is a rare but potentially life-threatening type of complication (1). The intimal tear and delamination process occur circumferentially, and the intimal flap separates from the aorta, partially or totally, with the detached tissue forced downstream. Furthermore, the intussuscepted flap can obstruct the aortic arch and its branches (1–3). Lack of typical imaging findings of type A aortic dissection can be a challenge due to the absence of intimal flap in the ascending aorta (1,3) (Figure).

CT angiographic images (A–C, axial multiplanar reformations [MPRs]; D, sagittal oblique; E, MPR extended; F, axial oblique; G, coronal; and H, oblique maximum intensity projection) show Stanford type A aortic dissection with an intimal flap in aortic root (arrowheads) and an intussuscepted intima (white arrow) in aortic arch, with the false lumen wrapped around the true lumen. Furthermore, no intimal flap was seen in ascending aorta (*). Right coronary artery (RCA) originates from true lumen and left main (LM) coronary artery from false lumen. Dissection also extends into the origin of the brachiocephalic trunk (black arrow) and left common carotid artery (image not included). LV = left ventricle.