Martin Lee David Gunn MBChB, Presenter: Nothing to Disclose

Michelle Bittle MD, Abstract Co-Author: Nothing to Disclose

Chitti Babu Naparla MD, Abstract Co-Author: Nothing to Disclose

Benjamin W. Starnes MD, Abstract Co-Author: Nothing to Disclose

Rachel S. Lundgren MD, Abstract Co-Author: Nothing to Disclose

Joel A. Gross MD, MS, Abstract Co-Author: Nothing to Disclose

To describe the MDCT imaging characteristics of blunt traumatic aortic injury (BTAI) not associated with contour abnormality to the outer wall (a.k.a. minimal aortic injury, isolated intimal injury). To determine the outcome following conservative and invasive treatment of these poorly understood injuries.

A retrospective review at a level 1 trauma center of radiology and discharge records between 2004 and 2009 was performed. Seventeen patients with BTAI without contour deformity were identified. Inclusion criteria were a trauma patient with either a aortic focal luminal filling defect, intimal irregularity atypical for an atheromatous plaque, or an intramural hematoma. Patients with contour abnormalities of the external surface of the aorta were excluded.

BTAI without external contour abnormality comprised 17/79 (21.5%) of all thoracic aortic injuries at our institution. The median injury severity score (ISS) of these patients was 38. All patients were involved in high energy blunt trauma, except one who was reported to have fallen 4 feet (ISS = 21). The most common finding was a focal aortic filling defect adherent to the internal wall of the aorta (13/17 patients, 82%). In two (18%) patients, there was an intimal flap and in two further patients there was an intramural hematoma. All but three patients in the group were treated conservatively, usually with anticoagulation and blood pressure control. There were no deaths or identifiable ischemic complications in the conservative group with a median follow-up of 102 days. Of those treated invasively, one patient underwent endovascular stenting and bypass surgery. This patient died three days later from ischemic complications. Two patients were treated with endovascular stenting and neither had complications. Imaging follow-up was performed in all but one of the conservatively treated patients and in 10/14 (71%) of these patients the area of concern in the aorta was normal on follow up.

BTAI without contour change represents 21% of aortic injuries. Most resolve spontaneously without surgery or endovascular repair. Conservative management of the smaller injuries appears safe.

MDCT has revolutionized the investigation of BTAI, and has lead to the recognition of this common but previously poorly characterized type of aortic injury that can be treated conservatively.

Gunn, M, Bittle, M, Naparla, C, Starnes, B, Lundgren, R, Gross, J, Blunt Thoracic Aortic Injury without Contour Deformity: Imaging Appearances and Outcome.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8002007.html