Terence Hong, Presenter: Nothing to Disclose

Jeanette Reyes, Abstract Co-Author: Nothing to Disclose

David Chiasson MD, Abstract Co-Author: Nothing to Disclose

Rahim Moineddin, Abstract Co-Author: Nothing to Disclose

Walter E Berdon MD, Abstract Co-Author: Nothing to Disclose

Paul S. Babyn MD, Abstract Co-Author: Nothing to Disclose

Postmortem thoracic imaging is often obtained for assessment of the ribs. The purpose of this study was to determine the potential additional value of thoracic CT compared with radiography using forensic pathologic examination (FPE) as a gold standard.

We retrospectively reviewed all coroner’s cases with both postmortem XR and CT skeletal survey acquired between January 2007 and October 2009. The study population included 1294 ribs from 55 patients (male = 35, female = 20, mean age = 1.0 years, patients less than 2 years = 45). In 11 patients (male = 8, female = 3, mean age = 1.7 years, patients less than 2 years = 7), 83 fractures were identified by FPE from among 250 ribs. All studies underwent initial review by two radiologists with the exception of 2 XR and 3 CT studies. The study radiologist reinterpreted all XR and CT images from the subset with positive findings, and determined the number, location, and presence or absence of healing for each fracture. Sensitivity and specificity was calculated for the reporting and study radiologists and compared using the Generalized Estimation Equation. 3D CT volume reconstructions were created and reviewed by the study radiologist following image reinterpretation.

CT improved overall sensitivity of the reporting and study radiologists by 17% and 38% respectively. For the reporting radiologists, differences in sensitivity between XR and CT did not reach significance. For the study radiologist, sensitivity of CT overall (p = 0.0122) and in anterior fractures (p = 0.0034) was significantly greater than XR. In addition, sensitivity of CT in fractures both with and without healing was significantly greater than XR (p < 0.05). Specificity for all readers was greater than 99% in both XR and CT.

Postmortem CT may detect significantly more pediatric rib fractures than XR, the majority of which may be anterior fractures. Radiologic-pathologic correlation suggests that overall sensitivity of post-mortem CT may be as high as 84% and that CT may identify fractures missed by autopsy. However, fractures will still be found at autopsy not seen by imaging. 3D CT volume reconstructions may be aid detection of subtle fractures missed by XR.

Increased sensitivity afforded by thoracic CT may be of particular importance in abuse cases where the detection of fractures may have medicolegal implications.

Hong, T, Reyes, J, Chiasson, D, Moineddin, R, Berdon, W, Babyn, P, Benefit of Thoracic CT over Radiography in Postmortem Imaging of Pediatric Rib Fractures: Radiologic-Pathologic Correlation.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9004595.html