Teresa I-Han Liang MD, Presenter: Nothing to Disclose

Patrick McLaughlin FFR(RCSI), Abstract Co-Author: Nothing to Disclose

Shamir Rai BSC, Abstract Co-Author: Nothing to Disclose

Darra Thomas Murphy MD, FRCPC, Abstract Co-Author: Nothing to Disclose

Luck Jan-Luck Louis MD, Abstract Co-Author: Nothing to Disclose

Tim O'Connell MD, Meng, Abstract Co-Author: President, Resolve Radiologic Ltd

Ana-Maria Bilawich MD, Abstract Co-Author: Nothing to Disclose

John R. Mayo MD, Abstract Co-Author: Speaker, Siemens AG

Savvas Nicolaou MD, Abstract Co-Author: Nothing to Disclose

Motion artifacts commonly reduce diagnostic confidence in patients with suspected blunt aortic injury. In this study we evaluate a novel iterative temporal resolution optimization (TRO) algorithm in patients with blunt chest trauma undergoing contrast enhanced ultra high pitch dual source CT.

Twenty-two patients who presented to a level one trauma centre between February 18 to March 25, 2014 with blunt thoracic trauma were included. All patients were scanned using a standardized ultra high pitch dual source CT protocol (UHP) using a single CT system. Aortic Motion artifact was scored using a five-point Likert scale modified from CCTA literature at multiple locations of the heart and aorta by two readers (Score of 1 = absence of motion artifacts or noise-related blurring in any vessels; score of 5 = severe or circumferential motion artifact, prominent mural discontinuity). Mean and standard deviation of CT values within aorta, muscle and air were recorded and signal to noise (SNR) and contrast to noise (CNR) ratios were generated as a quantitative index of image quality. Student t-test and Wilcoxon rank sum test were used for statistical analysis and p<0.05 was considered significant.

Aortic motion scores were significantly lower on UHP-TRO as compared with UHP images for both readers (Aortic valve 3.5±3 vs 5±2; Aortic sinus 1±1 vs 4±3; Sinotubular junction 1±1 vs 4±2; Ascending aorta 1±1 vs 3±2; p<0.0001). Motion scores were not significantly different at the aortic arch, isthmus and descending aorta on UHP-TRO as compared with UHP images (Arch 1±0 vs 1±0.75; Isthmus 1±0 vs 1±0.75; Descending aorta 1±0 vs 1±0.75). Mean SNR was 19.5% higher on UHP as compared with UHP-TRO (26.42 vs 21.27, p=0.01) and mean CNR scores were 27.7% higher on UHP images (13.4 vs 9.65, p=0.002).

Temporal Resolution optimized reconstruction of ultra high pitch dual-Source CT of the chest significantly improves motion artifact of the aorta in blunt thoracic trauma at the sacrifice of a mild reduction in SNR and CNR.

Iterative temporal resolution optimized reconstruction of ultra high pitch Dual-Source CT images of the chest qualitatively improves motion artifact in blunt thoracic trauma patients facilitating more accurate assessment of the aorta.

Liang, T, McLaughlin, P, Rai, S, Murphy, D, Louis, L, O'Connell, T, Bilawich, A, Mayo, J, Nicolaou, S, Dual-source CT of Chest in Blunt Thoracic Trauma: Reduced Aortic Motion Using a Novel Iterative Temporal Resolution Optimization Algorithm.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14017127.html