Perfusion patterns of peripheral pulmonary lesions in COVID-19 patients using contrast-enhanced ultrasound (CEUS): A case series.

PURPOSE: To describe perfusion patterns of peripheral pulmonary lesions (PPLs) in COVID-19 patients using contrast-enhanced ultrasound (CEUS). PATIENTS AND METHODS: From April 2020 until July 2020, 11 consecutive patients with RT-PCR-confirmed COVID-19 and PPLs sized over 5 mm were investigated by B-mode ultrasound (B-US) and CEUS. The homogeneity of enhancement (homogeneous and inhomogeneous) was examined retrospectively using CEUS. An inhomogeneous enhancement was defined as a perfused lesion with coexisting non-perfused areas (NPA). RESULTS: On B-US, all 11 patients showed an interstitial syndrome (B-lines) with PPLs between 0.5 and 6 cm. On CEUS, all cases showed peripheral NPA during the complete CEUS examination. One patient underwent a partial lung resection with subsequent histopathological examination. The histological examination showed vasculitis, microthrombus in the alveolar capillary, and small obliterated vessels. CONCLUSION: In our case series, PPLs in patients with RT-PCR-confirmed COVID-19 infection presented a CEUS pattern with NPA during the complete CEUS examination. Our findings suggest a peripheral pulmonary perfusion disturbance in patients with COVID-19 infection. In 1 case, the histopathological correlation with the perfusion disturbance in the PPL was proven.