Abstract
Introduction: An abnormal chest radiograph (CXR) can affect the ventilation-perfusion (V/Q) scan interpretation in the investigation of suspected pulmonary embolism (PE). V/Q scans are not always preceded by a normal CXR and many CXRs are reported as showing changes “compatible with COPD”.
We decided to ascertain whether radiological suspicion was supported by spirometric evidence of COPD and whether those with more severe COPD were more likely to have an intermediate probability V/Q scan.
Methods: All V/Q scans and CXR reports for the 12 months from February 2008 were analysed. The spirometry database was searched and results obtained.
Results: 68 patients had V/Q scans with CXRs reported as showing changes compatible with COPD. 44 (65%) had not had spirometry.
Of the 24 (35%) patients with spirometry, 3 reports were unavailable and 19 (90%) were consistent with COPD. The mean FEV1 was 60.2% predicted and the mean FEV1/FVC ratio was 50.7.
The V/Q scan reports are classified according to COPD severity in the table below.
Table 1
Conclusion: Of the 68 patients reported as having radiological “evidence” of COPD, only 24 (35%) had had spirometry. Of the 21 patients with spirometry reports available, 2 (9%) did not have COPD.
None of the patients with COPD had an intermediate probability VQ scan.
COPD is often “reported” on a chest radiograph but spirometric evidence is not always present and, if present, does not always confirm the radiological suspicion.
- © 2011 ERS
