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 47 - Breathing artifact simulating pulmonary embolism
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
Although CT pulmonary angiography (CTPA) is regarded by many as the reference standard for the diagnosis of pulmonary embolism in the acute setting, several studies have reported a high rate of non-diagnostic examinations due to poor image quality. In the PIOPED II study, which utilized 4-, 8-, and 16-channel CT scanners, nearly 10% of patients had an inconclusive scan. This was within the 6–11% range reported in other studies [1, 2]. The most common causes for an indeterminate CTPA are motion artifact and poor contrast enhancement [3]. Breathing artifact can be the cause of both, but rapid advances in CT technology have resulted in shorter scan times, reducing the frequency of these artifacts [4].
Despite optimal contrast timing, some patients still demonstrate suboptimal pulmonary arterial opacification, which can be either generalized or localized [5]. It is believed that this artifact is due to suspended deep inspiration with a Valsalva maneuver, which causes unopacified blood from the inferior vena cava to pass preferentially into the right heart and pulmonary arteries [5]. In patients with a patent foramen ovale the Valsalva maneuver may cause blood to pass preferentially from the right to the left heart [6]. This phenomenon has been termed “transient contrast bolus interruption.”
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- Pearls and Pitfalls in Emergency RadiologyVariants and Other Difficult Diagnoses, pp. 155 - 158Publisher: Cambridge University PressPrint publication year: 2013