On the Impact of Different Lung Ultrasound Imaging Protocols in the Evaluation of Patients Affected by Coronavirus Disease 2019: How Many Acquisitions Are Needed?

Abstract

Lung ultrasound (LUS) is currently being extensively used for the evaluation of patients affected by coronavirus disease 2019. In the past months, several imaging protocols have been proposed in the literature. However, how the different protocols would compare when applied to the same patients had not been investigated yet. To this end, in this multicenter study, we analyzed the outcomes of 4 different LUS imaging protocols, respectively based on 4, 8, 12, and 14 LUS acquisitions, on data from 88 patients. Results show how a 12-area acquisition system seems to be a good tradeoff between the acquisition time and accuracy.

Keywords: coronavirus disease 2019; lung ultrasound; point-of-care ultrasound; ultrasound imaging.

Figure 1

The overall distribution of assigned scores divided per specific area (anterior, lateral, and posterior) is depicted on the left side. The percentage of scores assigned for each area and for each patient is depicted in the center. The level of agreement for all of the patients’ scanning in the different areas is shown on the right side (For further details about the structure of agreement graphs, see Smargiassi et al. ⁵ ) Each patient was classified according to the worst score. The reference system is system 4.

Figure 2

The overall distribution of score considering the 4 systems is depicted on the top left. The level of agreement between systems 1, 2, and 3 with respect to system 4 is also shown on the top. (For further details about the structure of agreement graphs, see Smargiassi et al. ⁵ ) The distribution of each score in the posterior areas (basal, middle, and apical) is also depicted on the bottom left. The level of agreement between the 3 modified versions of system 4 (10 zones instead of 14: ie, all of the anterior and lateral areas together with apical posteriors, middle posteriors, or basal posteriors) with respect to system 4 is also shown on the top.