Book contents
- Frontmatter
- Contents
- List of contributors
- Preface
- Acknowledgments
- Section 1 Brain, head, and neck
- Section 2 Spine
- Section 3 Thorax
- Section 4 Cardiovascular
- Case 39 Aortic pulsation artifact
- Case 40 Mediastinal widening due to non-hemorrhagic causes
- Case 41 Aortic injury with normal mediastinal width
- Case 42 Retrocrural periaortic hematoma
- Case 43 Mimicks of hemopericardium on FAST
- Case 44 Mimicks of acute thoracic aortic syndromes: aortic dissection, intramural hematoma, and penetrating aortic ulcer
- Case 45 Aortic intramural hematoma
- Case 46 Pitfalls in peripheral CT angiography
- Case 47 Breathing artifact simulating pulmonary embolism
- Case 48 Acute versus chronic pulmonary thromboembolism
- Case 49 Vascular embolization of foreign body
- Section 5 Abdomen
- Section 6 Pelvis
- Section 7 Musculoskeletal
- Section 8 Pediatrics
- Index
- References
Case 40 - Mediastinal widening due to non-hemorrhagic causes
from Section 4 - Cardiovascular
Published online by Cambridge University Press: 05 March 2013
- Frontmatter
- Contents
- List of contributors
- Preface
- Acknowledgments
- Section 1 Brain, head, and neck
- Section 2 Spine
- Section 3 Thorax
- Section 4 Cardiovascular
- Case 39 Aortic pulsation artifact
- Case 40 Mediastinal widening due to non-hemorrhagic causes
- Case 41 Aortic injury with normal mediastinal width
- Case 42 Retrocrural periaortic hematoma
- Case 43 Mimicks of hemopericardium on FAST
- Case 44 Mimicks of acute thoracic aortic syndromes: aortic dissection, intramural hematoma, and penetrating aortic ulcer
- Case 45 Aortic intramural hematoma
- Case 46 Pitfalls in peripheral CT angiography
- Case 47 Breathing artifact simulating pulmonary embolism
- Case 48 Acute versus chronic pulmonary thromboembolism
- Case 49 Vascular embolization of foreign body
- Section 5 Abdomen
- Section 6 Pelvis
- Section 7 Musculoskeletal
- Section 8 Pediatrics
- Index
- References
Summary
Imaging description
The approach to non-traumatic, non-hemorrhagic causes of mediastinal widening on emergency radiographs can be divided into broad diagnostic categories. Imaging findings will vary depending on the cause, but CT will invariably be diagnostic.
Mediastinal widening is perhaps the best known radiographic sign of blunt thoracic aortic injury (BTAI). However, the definition of a widened mediastinum varies. Quantitatively, it refers to a mediastinal width of 8 cm at the level of the aortic arch on a supine (or erect) chest anterior-posterior radiograph [1]. Due to variation in patient size, mediastinum to chest-width ratios of (>0.25 [and >0.38]) have been suggested as more accurate measures, but these have not been found to be consistently sensitive [2]. Supine radiography has a poor specificity for aortic injury [2]. Although it offers greater specificity, an erect chest radiograph often cannot be obtained in unstable trauma patients and in the setting of a potential spine injury. No single radiographic sign has adequate specificity or sensitivity for the diagnosis or exclusion of aortic injury in patients with a BTAI. The specificity and sensitivity of radiographic evaluation is increased by considering a combination of other suggested signs. These include an abnormal aortic knob contour, shift of the tracheal wall to the right of the T4 transverse process, rightward deviation of the nasogastric tube, an apical pleural cap, widened paraspinal lines, or depression of the left main bronchus [2]. For a detailed discussion of the signs of aortic injury see Case 41.
- Type
- Chapter
- Information
- Pearls and Pitfalls in Emergency RadiologyVariants and Other Difficult Diagnoses, pp. 133 - 137Publisher: Cambridge University PressPrint publication year: 2013