Radiography is less sensitive relative to CT for detecting thoracic radiographic changes in dogs affected by blunt trauma secondary to a motor vehicle accident.

Thoracic injuries caused by blunt trauma are commonly encountered emergencies in veterinary medicine. However, published studies are lacking that compare radiology to CT in blunt trauma caused by motor vehicle accidents in canine patients. The aim of this prospective diagnostic accuracy, methods comparison study were to estimate the sensitivity (Se) and specificity (Sp) of thoracic radiology relative to CT for detecting lung contusions, pneumothorax, pleural effusion, and rib fractures. The study further aimed to develop a severity scoring system for radiology and CT and to compare the findings between the two modalities. The hypothesis was that radiology would be less sensitive than CT at detecting these injuries and that radiology would underestimate the severity of lung contusions. Fifty-nine patients met the inclusion criteria. Radiology underestimated the presence of lung contusions (Se = 69%, 95% confidence interval) and overestimated the severity of the contusions relative to CT. There was high interobserver variability in evaluating lung contusion severity (coefficient of variation = 91%). Both the three-view thoracic and horizontal beam radiography had poor sensitivities for the detecting pneumothorax (Se = 19% and 63%, respectively) and pleural effusions (Se = 43% and 71%, respectively). Similarly, the sensitivity (56%) of radiographs for the detection of rib fractures was poor relative to CT. Findings from the current study indicated that thoracic radiography had low sensitivity for detecting lesions related to blunt thoracic trauma caused by motor vehicle accidents and supported the use of CT as an additional diagnostic imaging modality in these patients.