Bryan Robert Foster MD, Presenter: Nothing to Disclose

Stephan Anderson MD, Abstract Co-Author: Nothing to Disclose

Jennifer W. Uyeda BS, Abstract Co-Author: Nothing to Disclose

James Travis Rhea MD, Abstract Co-Author: Stockholder, General Electric Company

Jorge A. Soto MD, Abstract Co-Author: Researcher, General Electric Company Researcher, Koninklijke Philips Electronics NV Researcher, Bracco Group Researcher, Schering AG (Berlex Inc)

To describe our experience integrating lower extremity CT angiography (CTA) into whole body CT trauma imaging with 64-MDCT, utilizing a single contrast bolus.

The IRB approved this HIPAA compliant retrospective study. All patients who underwent CTA of the lower extremities as part of a multi-phasic CT scan for trauma between May 2005 and March 2007 were included. Scans were acquired with a LightSpeed VCT scanner (GE Medical Systems, Milwaukee, WI). Intravenous contrast was administered at a rate of 4-5 mL/sec for a total of 100mL. The CTA encompassed the joints proximal and distal to the injured region. Scan delay for the CTA was fixed at 25 seconds. A CT of the chest (angiographic phase) and abdomen and pelvis (portal venous phase) immediately followed the CTA. Findings on conventional angiography, surgery or clinical follow-up, as determined by review of electronic medical records, were used as standard of reference. CT image quality was judged as optimal or suboptimal for diagnosis by a consensus of two radiologists.

Over the 22 months, 151 patients met inclusion criteria. Mechanism of trauma was blunt in 125 (83%) and penetrating in 26 (17%). Eight (5.3%) angiograms were nondiagnostic due to improper timing or excessively rapid z-axis coverage leading to “outrunning” the bolus of contrast. Repeat dedicated extremity CT angiograms were performed on 4 patients with nondiagnostic exams within 8 hours of the initial exam, while the remaining 4 patients underwent observation. No chest or abdomino-pelvic exams suffered from poor quality as a result of performing CTA. Eighteen (11.9%) of the 151 integrated CT angiograms were positive for major arterial injury in 27 individual arterial segments (occlusion = 17, active extravasation = 7, narrowing = 3).

Integration of lower extremity CTA into whole body trauma imaging is feasible and results in optimal image quality in the majority of patients. Total contrast load can be reduced using this method in multi-trauma patients.

Integrated CT angiography of the lower extremities with whole body trauma exams provides rapid evaluation of the vasculature at a reduced contrast volume.

Foster, B, Anderson, S, Uyeda, J, Rhea, J, Soto, J, Integration of 64-MDCT Extremity CT Angiography into Whole Body Trauma Imaging: Feasibility and Early Experience.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5004401.html