Ultrasound in diagnosis of COVID-19 in Pregnant Women
Moro et al 34devised pathological ultrasound patterns in pregnant females when compared to those expected in a normal lung, with particular emphasis on those more indicative of COVID-19 infection. The normal lung ultrasound will show A-Lines which are hyperechoic, repetitive reverberations, at regular intervals of the pleural line. The authors discuss 4 different presentations:
  1. B-Lines: These occur when the lung loses normal aeration, but is not completely consolidated, it creates vertical artifacts of varying lengths and shapes, referred to as the B-Lines. These can occur in the setting of interstitial lung disease, pulmonary fibrosis etc. and have to be clinically correlated. With early stages of COVID-19, the pleural line is usually irregular, thickened, and have a characteristic distribution (multifocal, monofocal, patchy etc.) surrounded by normal lung field and no gravitational distribution.
  2. White Lung: When the density of the peripheral lung parenchyma is increased as in the settings of SARS-CoV-2 acute respiratory distress syndrome (ARDS), ultrasound examination shows a white area which has no visible A or B lines.
  3. Consolidation: This presentation occurs in the setting of pneumonia or atelectasis, when the lung is almost completely collapsed. In pathology such as COVID-19 pneumonia, advanced ARDS, or bronchiolitis, the lung may present only small subpleural, hypoechoic consolidations.
  4. Pleural Effusion: In general, pleural effusion can be simple and uniformly anechoic or complicated by the presence of hyperechoic spots due to blood, pus, fibrin and/or septa.