Keywords:
Pathology, Embolism / Thrombosis, Acute, Observer performance, Education, CT-Angiography, CT, Vascular, Pulmonary vessels, Cardiovascular system
Authors:
S.-M. O'Hanlon, T. Wooding, A. Mittal, Y. D. Weerakkody; Perth/AU
Methods and Materials
This study was approved by the Royal Perth Hospital Human Research Ethics Committee.
A search of all CTPA studies performed between 1 January 2016 and 31 July 2017 at our tertiary institution,
Royal Perth Hospital,
was performed searching the local Radiology Information System platform.
Studies that had been reported as demonstrating pulmonary emboli were identified and collated for independent imaging review by the thoracic subspecialist imaging team. A positive study was defined as one having a pulmonary arterial filling defect (Fig. 1) lacking appearances typical of an artifact.
Inclusion criteria
All positive CTPA studies performed at Royal Perth Hospital within the defined study period were included in the study.
Exclusion criteria
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Patients less than 18 years of age.
-
Follow-up studies for known pulmonary embolism.
-
Studies repeated for technical reasons.
-
Patients with known pulmonary embolism mimics.
Additional definitions
- “Central” pulmonary embolism: a filling defect consistent with thrombus identified within the main pulmonary trunk,
left main pulmonary artery or right main pulmonary artery.
- “Peripheral” pulmonary embolism: a filling defect consistent with thrombus identified within lobar,
segmental or subsegmental arteries.
CT examinations were reviewed,
recording:
- Patient demographics: age,
gender
-
Vessel(s) containing emboli
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Associated features: right heart strain,
pulmonary hypertension,
mosaic perfusion,
pulmonary infarcts,
presence of webs or bands,
eccentric or central luminal clot location
-
Established COPD changes on CT
-
Known malignancy
-
Evidence of concurrent thoracic pathology
Collected data were summarised using counts and proportions.