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.