Reproduced, with permission, from Bahnson HT, Nelson AR Reproduced, with permission, from Bahnson HT, Nelson AR. Cystic medial necrosis as a cause of localized aortic aneurysms amenable to surgical treatment. Ann Surg. 1956;144:519–529. Source: Ascending Thoracic Aorta and Aortic Arch, Peripheral Arterial Disease Citation: Dieter RS, Dieter RA, Jr., Dieter RA, III. Peripheral Arterial Disease; 2016 Available at: http://accesscardiology.mhmedical.com/DownloadImage.aspx?image=/data/books/1789/dieperi_ch27_f011.png&sec=123048124&BookID=1789&ChapterSecID=123048045&imagename= Accessed: November 09, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved