Missed rib fractures on evaluation of initial chest CT for trauma patients: pattern analysis and diagnostic value of coronal multiplanar reconstruction images with multidetector row CT

Abstract

Objective: The objective of this study was to review the prevalence and radiological features of rib fractures missed on initial chest CT evaluation, and to examine the diagnostic value of additional coronal images in a large series of trauma patients. Methods: 130 patients who presented to an emergency room for blunt chest trauma underwent multidetector row CT of the thorax within the first hour during their stay, and had follow-up CT or bone scans as diagnostic gold standards. Images were evaluated on two separate occasions: once with axial images and once with both axial and coronal images. The detection rates of missed rib fractures were compared between readings using a non-parametric method of clustered data. In the cases of missed rib fractures, the shapes, locations and associated fractures were evaluated. Results: 58 rib fractures were missed with axial images only and 52 were missed with both axial and coronal images (p50.088). The most common shape of missed rib fractures was buckled (56.9%), and the anterior arc (55.2%) was most commonly involved. 21 (36.2%) missed rib fractures had combined fractures on the same ribs, and 38 (65.5%) were accompanied by fracture on neighbouring ribs. Conclusion: Missed rib fractures are not uncommon, and radiologists should be familiar with buckle fractures, which are frequently missed. Additional coronal imagescan be helpful in the diagnosis of rib fractures that are not seen on axial images.

Enhanced reading time efficiency by use of automatically unfolded CT rib reformations in acute trauma

“…It has already been shown that the use of MPR or volume rendered (VR) images in comparison to transverse CT images may improve the detection rate [11,12]. We used CT images with 1 mm slice thickness allowing for three-dimensional reformation and compared these to the unfolded rib images.…”

“…The fracture location was subdivided into an anterior, lateral and posterior part, as previously described by Cho et al [11] and Livingston et al [14]. Accordingly, missed fractures were sub-classified in terms of localization (anterior, lateral, posterior) and fracture characteristics (normal/dislocated/buckled/incomplete).…”

“…Multi-detector computed tomography (MDCT) is the diagnostic modality of choice in patients with polytrauma with suspected thoracic involvement [10]. Rib fractures are commonly missed on regularly acquired transverse images and diagnostic accuracy can only slightly be enhanced by additional analysis of coronal multiplanar reformation (MPR) images [11]. An approach by Alkadhi et al [12] showed, that three-dimensional images significantly decreased the total reading time of CT scans in chest trauma patients.…”

Usefulness of low dose chest CT for initial evaluation of blunt chest trauma

“…Pneumomediastinum was differentiated from pneumothorax by the presence of the internal septa. [11–15] Hemothorax, hemopericardium, hemoperitoneum were defined as “blood density (30–100 HU) within the pleural cavity, pericardium and abdominal cavity,” respectively. Mediastinal hematoma was defined as “inhomogeneous soft tissue density within the mediastinal fat, with obscuration or obliteration.” Chest wall hematoma was defined as “area of soft tissue density causing anatomical alteration.” We are aware of the critical limitation for assessment of aortic injury and upper abdominal injury using non-contrast CT, so LDCT without contrast enhancement of this current study was not appropriate for proper evaluation of aortic injury and upper abdominal injury.…”

Thoracic wall trauma—misdiagnosed lesions on radiographs and usefulness of ultrasound, multidetector computed tomography and magnetic resonance imaging

“…A nondisplaced rib fracture is defined as a rib fracture with complete cortical disruption but with maintained alignment, usually involving the medullar bone and both the inner and outer cortices ( Figure 1); it is seen such a lucent line on radiographs or CT images (14). Stress rib fractures are overuse injuries that occur when there is an abnormal force on normal underlying bone.…”