Detection of peripheral embolic consolidations using contrast-enhanced ultrasonography in patients with no evidence of pulmonary embolism on computed tomography: A pilot study.

AIM

To investigate the value of B-mode imaging and contrast-enhanced ultrasonography (CEUS) in patients with clinically suspected pulmonary embolism (PE) but no evidence of central PE on CT.

METHODS

Between May 2004 and February 2015, we included in this retrospective study 19 patients with a risk profile for PE according to their Wells' score, sonographic patterns of peripheral embolic consolidations (EC) on B-mode-imaging and CEUS (ie, missing or inhomogeneous enhancement of the pleural lesions), and exclusion of central PE by CT within 1 week of CEUS.

RESULTS

On B-mode imaging, 19 pleural defects presented as hypoechoic. The shape of EC was round in 2, wedge-shaped in 12, polygonal in 3, and presented as atelectasis in 2 cases. On CEUS, 5 of the defects demonstrated, at the arterial and parenchymal phase, a lack of enhancement, and 14 showed an inhomogeneous (mixed) enhancement with wedge-shaped peripheral areas of no contrast enhancement. A second radiologic evaluation of the CT scans revealed PE in two patients and lesions suspicious for malignancy in two other patients.

CONCLUSIONS

Despite the lack of definite confirmation of peripheral and central PE on CT, peripheral pleural consolidations with no or inhomogeneous enhancement on CEUS, in combination with the risk profile for a PE, are highly suggestive of EC. If there is still some doubt, histologic confirmation is important to confirm EC and exclude malignancy. Thus, CEUS may close a potential diagnostic gap of small peripheral PE on CT. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:575-579, 2017.