Fig. 1From: Diagnostic value of cardiopulmonary ultrasound in elderly patients with acute respiratory distress syndromeThe four chest areas per side considered for complete twelve- zone lung ultrasound examination. Areas 1 and 2 denote the upper anterior and lower anterior chest areas, respectively. Areas 3 and 4 denote the upper lateral and basal lateral chest areas, respectively. PSL parasternal line, AAL anterior axillary line, PAL posterior axillary line.Back to article page