Aortic branch artery pseudoaneurysms accompanying aortic dissection. Part II. Distinction from penetrating atherosclerotic ulcers.

PURPOSE Small collections of contrast material are frequently seen within the otherwise thrombosed false lumen of an aortic dissection (AD). These collections can be divided into those without apparent communication with the aortic lumen (ie, pseudoaneurysms) and those with obvious communications (ie, ulcers). The present study was performed to test the hypotheses that pseudoaneurysms and ulcers differ in their distribution around the aorta and that the distribution of pseudoaneurysms is similar to that of small aortic branch arteries. MATERIALS AND METHODS Computed tomography (CT) scans in 187 patients with AD and thrombosed false lumens showed 335 intramural contrast medium collections, including 128 pseudoaneurysms and 207 ulcers. CT scans in 40 control individuals without AD were reviewed to localize small aortic branch arteries. The angular distributions around the circumference of the aorta of pseudoaneurysms and ulcers and the branch artery origins were tabulated and compared. The frequency of detection of small branch arteries arising from the contrast material collections was noted. RESULTS The angular distribution of pseudoaneurysms did not differ significantly from that of branch artery origins but did differ from that of ulcers. Pseudoaneurysms were found along the posterior, medial, and anterior walls of the aorta in the chest, sparing the lateral wall abutting the pleura. Ulcers tended to spare the arc containing branch artery origins. The composite distribution of ulcers and pseudoaneurysms appears uniform around the circumference of the aorta except at the T10-T12 levels. CONCLUSIONS Branch artery pseudoaneurysms spare the pleural surface of the aorta and have nearly the same distribution around the circumference of the aorta as the origins of small aortic branch arteries. In contrast, ulcers tend to spare branch artery origins. The characteristic appearance and distribution of pseudoaneurysms on CT can help differentiate them from ulcers.

[1]  J. Tisnado,et al.  Ulcerlike projections: a precursor angiographic sign to thoracic aortic dissection. , 1980, AJR. American journal of roentgenology.

[2]  J. Elefteriades,et al.  Penetrating ulcer of the thoracic aorta: what is it? How do we recognize it? How do we manage it? , 1998, Journal of vascular surgery.

[3]  R. S. Mitchell,et al.  Prognosis of Aortic Intramural Hematoma With and Without Penetrating Atherosclerotic Ulcer: A Clinical and Radiological Analysis , 2002, Circulation.

[4]  E. Kazerooni,et al.  Penetrating atherosclerotic ulcers of the descending thoracic aorta: evaluation with CT and distinction from aortic dissection. , 1992, Radiology.

[5]  L. Quint,et al.  Ulcerlike lesions of the aorta: imaging features and natural history. , 2001, Radiology.

[6]  J. Cooke,et al.  The penetrating aortic ulcer: pathologic manifestations, diagnosis, and management. , 1988, Mayo Clinic proceedings.

[7]  David M. Williams,et al.  A biologic basis for asymmetric growth in descending thoracic aortic aneurysms: a role for matrix metalloproteinase 9 and 2. , 2006, Journal of vascular surgery.

[8]  T. Sundt,et al.  Penetrating atherosclerotic ulcer of the descending thoracic aorta and arch. , 2004, Journal of Thoracic and Cardiovascular Surgery.

[9]  J. A. Harris,et al.  Penetrating atherosclerotic ulcers of the aorta. , 1994, Journal of vascular surgery.

[10]  P. Bendick,et al.  Penetrating atherosclerotic ulcers of the thoracic aorta. , 1989, Journal of vascular surgery.

[11]  P. Sheedy,et al.  Radiologic evaluation of penetrating aortic atherosclerotic ulcer. , 1990, Radiographics : a review publication of the Radiological Society of North America, Inc.

[12]  W. Edwards,et al.  Penetrating atherosclerotic ulcers of the thoracic aorta: natural history and clinicopathologic correlations , 1986, Annals of vascular surgery.

[13]  David M. Williams,et al.  Aortic branch artery pseudoaneurysms accompanying aortic dissection. Part I. Pseudoaneurysm anatomy. , 2006, Journal of vascular and interventional radiology : JVIR.

[14]  K. Hayashi,et al.  Penetrating atherosclerotic ulcer of the aorta: imaging features and disease concept. , 2000, Radiographics : a review publication of the Radiological Society of North America, Inc.

[15]  Hirst Ae,et al.  DISSECTING ANEURYSM OF THE AORTA: A REVIEW OF 505 CASES , 1958, Medicine.

[16]  J. Elefteriades,et al.  Midterm follow-up of penetrating ulcer and intramural hematoma of the aorta. , 2002, The Journal of thoracic and cardiovascular surgery.

[17]  M. Williams,et al.  Atypical patterns in the CT diagnosis of aortic dissection. , 1994, Clinical radiology.

[18]  Y. Moriyama,et al.  Penetrating Atherosclerotic Ulcer , 2001, Surgery Today.

[19]  M. Uetani,et al.  Fate of intramural hematoma of the aorta: CT evaluation. , 1997, Journal of computer assisted tomography.