Abstract
Abdominal aortic aneurysms are commonly encountered during abdominal CT imaging, and size-based parameters for surgical or endovascular repair are well established. Aneurysms greater than 5 cm in diameter are recognized as representing an increased rupture risk and meriting intervention. Increasingly, additional interest has been generated in recognizing imaging features which may herald instability and portend a higher chance for potentially catastrophic rupture. This article will review and illustrate such signs, including hyperattenuation of mural thrombus, rapid expansion, low thrombus to lumen ratio, intimal calcification disruption, posterior mural draping, and saccular outpouching. Other features of complicated abdominal aneurysms including perianeurysmal inflammation, aortocaval and aortoenteric fistula formation will also be addressed. Heightened awareness of these features and their prognostic implications, as well as timely communication with the clinical service, is critical for the interpreting radiologist.
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References
Scott R, Ashton H, Kay D (1991) Abdominal aortic aneurysm in 4,237 screened patients: prevalence, development and management over 6 years. Br J Surg 78:1122–25
MacSweeney S, Powell J, Greenhalgh R (1994) Pathogenesis of abdominal aortic aneurysm. Br J Surg 81(7):935–941
Wadgaonkar A, Black J, Zimmerman S et al (2015) Abdominal aortic aneurysms revisited: MDCT with multiplanar reconstructions for identifying indicators of instability in the pre- and postoperative patient. Radiographics 35:254–268
Bengtsson H, Bergqvist D, Sternby N (1992) Increasing prevalence of abdominal aortic aneurysms: a necropsy study. Eur J Surg 158:19–23
Rao P, Novelline R (1996) Radiologic features and anatomic basis of atypical clinical presentations of ruptured abdominal aortic aneurysms. Emerg Radiol 3(4):166–171
Rakita D, Newatia A, Hines J et al (2007) Spectrum of CT findings in rupture and impending rupture of abdominal aortic aneurysms. Radiographics 27:497–507
Nathan D, Boonn W, Lai E et al (2012) Presentation, complications, and natural history of penetrating atherosclerotic ulcer disease. J Vasc Surg 55(1):10–15
Quint L, Williams D, Francis I et al (2001) Ulcerlike lesions of the aorta: imaging features and natural history. Radiology 218:719–723
Sprouse L 2nd, Meier G 3rd, Parent F et al (2004) Is three-dimensional computed tomography reconstruction justified before endovascular aortic aneurysm repair? J Vasc Surg 40(3):443–447
Johnson P, Fishman E (2006) IV contrast selection for MDCT: current thoughts and practice. AJR 186(2):406–415
Bryce Y, Rogoff P, Romanelli D et al (2015) Endovascular repair of abdominal aortic aneurysms: vascular anatomy, device selection, procedure, and procedure-specific complications. Radiographics 35:593–615
Raux M, Marzelle J, Kobeiter H et al (2015) Endovascular balloon occlusion is associated with reduced intraoperative mortality of unstable patients with ruptured aortic aneurysms but fails to improve other outcomes. J Vasc Surg 61(2):304–308
Siegel C, Cohan R, Korobkin M et al (1994) Abdominal aortic aneurysm morphology: CT features in ruptured and non-ruptured aneurysms. AJR 163:1123–1129
Taheri M, Haghighatkha H, Pourghorban R et al (2013) Multidetector computed tomography findings of abdominal aortic aneurysm and its complications: a pictorial review. Emerg Radiol 20(5):443–451
Mussa F (2015) Screening for abdominal aortic aneurysm. J Vasc Surg 62(3):774–778
Thompson S, Brown L, Sweeting M et al (2013) Systematic review and meta-analysis of the growth and rupture ratios of small abdominal aortic aneurysms: implications for surveillance intervals and their cost effectiveness. Health Technol Assess 41:1–118
Chaikof E, Brewster D, Dalman R, et al. (2009) The care of patients with an abdominal aortic aneurysm: the Society for Vascular Surgery practice guidelines; 50(4 suppl): S2-S49
Mehard W, Heiken J, Sicard G (1994) High-attenuating crescent in abdominal aortic aneurysm wall at CT: a sign of acute or impending rupture. Radiology 192(2):359–362
Pillari G, Chang J, Zito J et al (1988) Computed tomography of abdominal aortic aneurysm an in vivo pathological report with a note on dynamic predictions. Arch Surg 123(6):727–732
Mower W, Quinones W, Gambhir S (1999) Effect of intraluminal thrombus on abdominal aortic aneurysm wall stress. J Vasc Surg 26:602–608
Szilagyi D, Smith R, Macksood A et al (1961) Expanding and ruptured abdominal aortic aneurysms. Problems of diagnosis and treatment. Arch Surg 83:395–408
Sterpetti A, Blair E, Schultz R et al (1990) Sealed rupture of abdominal aortic aneurysms. J Vasc Surg 11:430–435
Apter S, Rimon U, Konen E et al (2010) Sealed rupture of abdominal aortic aneurysms: CT features in 6 patients and a review of the literature. Abdom Imaging 35:99–105
Halliday K, Al-Kutoubi A (1996) Draped aorta: CT sign of contained leak of aortic aneurysms. Radiology 199:41–43
Kapoor V, Kanal E, Fukui M (2001) Vertebral mass resulting from a chronic-contained rupture of an abdominal aortic aneurysm repair graft. AJNR 22:1775–1777
Sato M, Imai A, Sakamoto H et al (2012) Abdominal aortic disease caused by penetrating atherosclerotic ulcers. Ann Vasc Dis 5(1):8–14
Batt M, Haudebourg P, Planchard P et al (2005) Penetrating atherosclerotic ulcers of the infrarenal aorta: life-threatening lesions. Eur J Vasc Endovasc Surg 29(1):35–42
Taylor B, Kalman P (1999) Saccular aortic aneurysms. Ann Vasc Surg 13:555–559
Hellmann D, Grand D, Freischlag J (2007) Inflammatory abdominal aortic aneurysm. JAMA 297(4):395–400
Tang T, Boyle J, Dixon A et al (2005) Inflammatory abdominal aortic aneurysms. Eur J Vasc Endovasc Surg 29:353–362
Vaglio A, Buzio C (2005) Chronic periaortitis: a spectrum of diseases. Curr Opin Rheumatol 17:34–40
Haug E, Skomsvoll J, Jacobsen G et al (2003) Inflammatory aortic aneurysm is associated with increased incidence of autoimmune disease. J Vasc Surg 38:492–497
Arrive L, Correas J, Leseche G (1995) Inflammatory aneurysms of the abdominal aorta: CT findings. AJR 165:1481–1484
Rasmussen T, Hallett J (1997) Inflammatory aortic aneurysms—a clinical review with new perspectives in pathogenesis. Ann Surg 225:155–164
Coppi G, Francesco R, Aiello S et al (2010) Inflammatory abdominal aortic aneurysm endovascular repair into the long-term follow-up. Ann Vasc Surg 24(8):1053–1059
Raman S, Kamaya A, Federle et al (2013) Aortoenteric fistulas: spectrum of CT findings. Abdom Imaging 38:367–375
Paulus E, Garrett H, Powell B et al (2013) Primary aortoduodenal fistula after radiotherapy. Am Surg 79(4):E158–159
Hagspiel K, Turba U, Bozlar U et al (2007) Diagnosis of aortoenteric fistulas with CT angiography. J Vasc Interv Radiol 19:497–504
Vilas-Boas F, Azevedo F, Marques M et al (2013) Primary aortoenteric fistula. Clin J Gastroenterol 6:299–302
Saers S, Scheltinga M (2005) Primary aortoenteric fistula. Br J Surg 92(2):143–152
Muller B, Wegener O, Grabitz K et al (2001) Mycotic aneurysms of the thoracic and abdominal aorta and iliac arteries: experience with anatomic and extra-anatomic repair in 33 cases. J Vasc Surg 33:106–113
Hsu R, Tsay Y, Wang S et al (2002) Surgical treatment for primary infected aneurysm of the descending thoracic aorta, abdominal aorta and iliac arteries. J Vasc Surg 36:873–879
Azhmed M, Ling L, Ettles D (2013) Common and uncommon CT findings in rupture and impending rupture of abdominal aortic aneurysms. Clin Radiol 68:962–971
Gonda R, Gutierrez O, Azodo M (1988) Mycotic aneurysms of the aorta: radiologic features. Radiology 168:343–346
Salzberger L, Cavuoti D, Bernard J (1983) Fatal Salmonella infection of the abdominal aorta. Rev Infec Dis 5:227–231
Oderich G, Panneton J, Bower T et al (2001) Infected aortic aneurysms: aggressive presentation. Complicated early outcome, but durable results. J Vasc Surg 34:900–908
Kan C, Lee H, Yang Y (2007) Outcome after endovascular stent graft treatment for aortic mycotic aneurysm: a systematic review. J Vasc Surg 46:906–912
Dick J, Tiwari A, Menon J et al (2010) Abdominal aortic aneurysm secondary to infection with Pseudomonas aeruginosa: a rare cause of mycotic aneurysm. Ann Vasc Surg 24:692e1–692e4
Fenster M, Dent J, Tribble C et al (1996) Aortocaval fistula complicating abdominal aortic aneurysm: case report and literature review. Catheter Cardiovasc Diagn 38:75–79
Rajmohan B (2002) Spontaneous aortocaval fistula. J Postgrad Med 48:203–205
Coulier B, Tilquin O, Etienne P (2004) Multidetector row CT diagnosis of aortocaval fistula complicating aortic aneurysm: a case report. Emerg Radiol 11:100–103
Kopp R, Weidenhagen R, Hoffmann R et al (2006) Immediate endovascular treatment of an aortoiliac aneurysm ruptured into the inferior vena cava. Ann Vasc Surg 20(4):525–528
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Sever, A., Rheinboldt, M. Unstable abdominal aortic aneurysms: a review of MDCT imaging features. Emerg Radiol 23, 187–196 (2016). https://doi.org/10.1007/s10140-015-1374-x
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DOI: https://doi.org/10.1007/s10140-015-1374-x