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Emergency Radiology

, Volume 26, Issue 1, pp 29–35 | Cite as

Computed tomography for suspected pulmonary embolism results in a large number of non-significant incidental findings and follow-up investigations

  • Omar Anjum
  • Helena Bleeker
  • Robert OhleEmail author
Original Article

Abstract

Introduction

Computed tomographic pulmonary angiograms (CTPAs) are often ordered to evaluate pulmonary embolism (PE) in the emergency department (ED). The increase use of CTPA has led to an increase in incidental findings, often of low clinical significance. Our objectives were to (1) assess the prevalence and clinical significance of incidental findings identified in patients evaluated with CTPAs for PE in the ED, (2) evaluate follow-up investigations for these incidental findings, and (3) assess the utility of routine chest X-rays done prior to CTPA.

Methods

This is a historical cohort study of adult patients, presenting to two tertiary care EDs from January–December 2015, evaluated with CTPA for possible PE. Two reviewers’ extracted data from electronic CT records in a standardized fashion with inter-rater reliability reported using the kappa statistic. We measured the prevalence of PE and stratified non-PE findings according to alternative diagnoses and incidental findings. Data were reported as mean and standard deviation (SD). Univariate analyses were performed with t test for continuous variables.

Results

A total of 1708 studies were included (mean 62 years (SD 16.7), 56.9% female). PE was found in 233 (13.6%) patients. A total of 223 (13.1%) patients had an incidental finding, the majority of which included pulmonary nodules (n = 83, 37.2%) and adenopathy (n = 26, 11.6%). Of the incidental findings, 197 (88.3%) were non-significant and led to no definitive diagnosis of cancer. In patients who underwent both CTPA and chest X-ray, X-ray reports revealed the same diagnosis in 77% of PE-negative patients without missing a clinically significant incidental finding.

Conclusions

Incidental findings are as common as a diagnosis of PE in patients undergoing CTPA. They are rarely clinically significant. Chest radiograph remains a reasonable initial investigation as it can aid in identifying alternative diagnoses especially in the setting of a low pre-test probability for PE.

Keywords

Computed tomography Incidental findings Pulmonary embolism Chest X-ray 

Notes

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

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Copyright information

© American Society of Emergency Radiology 2018

Authors and Affiliations

  1. 1.Department of Undergraduate MedicineUniversity of OttawaOttawaCanada
  2. 2.The Department of Emergency Medicine, Health Science North Research InstituteNorthern Ontario School of MedicineThunder BayCanada
  3. 3.The Ottawa HospitalOttawaCanada

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