RSNA 2014 

Abstract Archives of the RSNA, 2014


The Ribs Unfolded—A CT Visualization Algorithm for Fast Detection of Rib Fractures: Effect on Sensitivity and Specificity in Trauma Patients

Scientific Posters

Presented on December 4, 2014
Presented as part of ERS-THB: Emergency Radiology Thursday Poster Discussions


Mathias Lazar MD, Presenter: Nothing to Disclose
Thomas Georg Mang MD, Abstract Co-Author: Nothing to Disclose
Ulrika Asenbaum MD, Abstract Co-Author: Nothing to Disclose
Michael Weber, Abstract Co-Author: Nothing to Disclose
Grzegorz Soza, Abstract Co-Author: Employee, Siemens AG
Michael Toepker MD, Abstract Co-Author: Nothing to Disclose
Helmut R. Ringl MD, Abstract Co-Author: Institutional research collaboration, Siemens AG


To assess the radiologist’s detection rate of rib fractures in trauma CT when reading curved planar reformats (CPR) of the ribs compared to reading standard MPRs.


Written, informed consent was waived for this institutional review board-approved study. There were 220 consecutive trauma CTs (146 male and 74 female patients; mean age ± standard deviation, 42.6 years±21.4; range, 0-94 years) retrospectively subjected to a software algorithm (Syngo.Via CT Bone Reading, Siemens AG) for automatic generation of CPRs of the ribs. Patients were split into two equal groups. After primary analysis, 16 patients were excluded due to insufficient segmentation, leaving 107 patients in group A and 97 patients in group B. Two radiologists independently evaluated group A using CPRs and group B using standard MPRs. The other two radiologists reviewed both groups with the inverse methods setting. The detection rate results for each reader were compared with a standard of reference that was created by two senior radiologists using all available MPRs and CPRs and the findings of all readers. General estimation equations were used for statistical analysis.  


The reference standard identified 361 rib fractures in 61 patients. Reading CPRs showed a significantly higher mean sensitivity (P=<.001) for fracture detection than reading standard MPRs, with 80.9%(584/722) and 71.5%(516/722), respectively. Mean reading time was significantly shorter for CPRs, with 31.3 seconds, compared to standard MPRs, with 60.7 seconds (P<.001).


Using CPRs for the detection of rib fractures allows for accelerating the reading process in chest CTs of trauma patients, while offering an increased mean sensitivity compared to reading conventional standard MPRs.


1. Curved planar reformats (CPRs) can help radiologists to significantly decrease the reading time needed for analysis of the ribs in chest CT. This might accelerate the report and leave more time to assess other organs in polytrauma CT. 2. The accurate detection of rib fractures is clinically relevant to allow for sufficient treatment and for a focused search for associated complications.  

Cite This Abstract

Lazar, M, Mang, T, Asenbaum, U, Weber, M, Soza, G, Toepker, M, Ringl, H, The Ribs Unfolded—A CT Visualization Algorithm for Fast Detection of Rib Fractures: Effect on Sensitivity and Specificity in Trauma Patients.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL.