Arindam Rano Chatterjee MD, Presenter: Nothing to Disclose

Johnathan Hadley, Abstract Co-Author: Nothing to Disclose

Ashok Jayashankar MD, Abstract Co-Author: Nothing to Disclose

Sridhar Shankar MD, Abstract Co-Author: Nothing to Disclose

Tim Cramer, Abstract Co-Author: Nothing to Disclose

Anthony Braswell MD, Abstract Co-Author: Nothing to Disclose

To evaluate discrepant findings between computed tomographic angiography (CTA) and 4-vessel angiography (4VA) for the diagnosis of blunt cerebrovascular injury (CVI) in trauma patients.

Retrospective data was collected on patients presenting at our Level I trauma center with blunt trauma injuries (BTI) who underwent both CTA and 4VA.  The criteria for performing 4VA were independent of the CTA results. CTA and 4VA CVI discrepancies were examined from a technical limitation versus radiologist interpretation perspective to characterize these discrepancies.

Over 13 month, 3304 BTI patients presented to our Level I trauma center and 117 received both CTA and 4VA. Of these, 53 positive cases of CVI (45%) were concordant between the two modalities. 4VA found 19 cases of CVI (16%) initially missed on CTA.  On review, these were readily and independently identified in 15 of these 19 CVIs. CTA identified 34 cases (29%) of CVI that were subsequently called normal on 4VA. Of these 34 “False Positive” CTA findings: 26% (9) were called atherosclerotic stenosis, 21% (7) were clearly identified on subsequent review of the 4VA studies as positive injuries when correlated with the CTA finding, 21% (7) were a uique flow artifact on the CTA, 12% (4) were attributed to resident inexperience, and the remaining 18% (6) were attributed to other unique diagnoses. 

The overwhelming majority of false positive and false negative CTA and 4VA findings in blunt trauma patients with CVI at our institution are attributable to interpretation error and not due to technical modality limitations.  In this study, 22% of all injuries were missed at the initial CTA reading.  Over-reading of these studies, particularly in high risk patients, should be considered due to the high morbidity and mortality associated with blunt trauma CVI.

As CTA is increasingly used to screen for cerebrovascular injury, discrepant CTA and 4VA findings reveals interpretation errors account for a majority of misdiagnoses.

Chatterjee, A, Hadley, J, Jayashankar, A, Shankar, S, Cramer, T, Braswell, A, Computed Tomographic Angiography vs 4-Vessel Angiography: Teasing Apart Discrepant Findings for Blunt Cerebrovascular Injury in Trauma Patients.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9013807.html