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

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

Chesnal Dey Arepalli MD, Abstract Co-Author: Nothing to Disclose

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

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

Diaphragmatic injuries have a marked impact on the management and prognosis of trauma patients. Motion artifacts may obscure diaphragm injuries during CT of trauma patients with low Glascow Coma Scale (GCS) scores or those who are intubated and ventilated. CT acquisition times are dramatically reduced by using dual source ultra-high pitch (DS-UHP) as compared with conventional single source (SS) protocols. The purpose of this study was to evaluate diaphragmatic motion on simultaneously acquired DS-UHP and SS CT scans in trauma patients.

Seventy-five consecutive trauma patients who presented to a level one trauma centre over a 6 month period scanned with a standardized trauma protocol including both DS-UHP chest (pitch = 1.7-3.2) and SS abdominal CT scans (pitch =0.6) were reviewed retrospectively. Subjective analysis of diaphragmatic motion was performed in consensus by two readers using a 4 point likert scale in 7 regions of the diaphragm on coronal 3mm and axial 1mm-3mm slices. An overall confidence score to exclude a diaphragmatic tear based on all coronal and axial images available was also determined (1 to 10, 10 being completely confident and 1 being impossible to exclude). Wilcoxon Rank Sum tests were used for statistical analysis and p < 0.05 was considered significant.

The mean overall confidence score for the DS-UHP was 9.85, which was significantly better than the mean score of 7.66 for SS images (p < 0.0001). The scores for diaphragmatic motion on coronal and axial images were significantly better for DS-UHP images in all areas when compared individually (p < 0.0001). Additionally, utilizing the overall coronal image scores, the subjective diaphragmatic motion was significantly less in the DS-UHP images than the SS images (p < 0.0001).

Ultra high-pitch is advantageous as it allows for better evaluation of diaphragmatic structures by minimizing motion artifacts on images of freely breathing trauma patients.

An ultra high-pitch dual source mode is valuable in trauma patients who are unable to breath-hold as it allows minimization of motion artifacts of the diaphragm as compared with conventional single source reconstructions.

Liang, T, McLaughlin, P, Arepalli, C, Louis, L, Bilawich, A, Mayo, J, Nicolaou, S, Analysis of Diaphragmatic Motion Artifacts in Ultra High-Pitch Dual Source Computed Tomography of the Thorax in Trauma Patients.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014641.html