Process of performing lung US. A, Illustration demonstrates basic longitudinal and transverse probe orientations. B, C, A complete lung US examination includes transverse and longitudinal scans through the anterior, lateral, and posterior lungs. AAL = anterior axillary line, PAL = posterior axillary line, PSL = parasternal line, PVL = paravertebral line. (Reprinted, with permission, from University of Rochester, Rochester, New York © 2021; medical illustration by Gwen Mack and Nadezhda D. Kiriyak and photographs by Sarah Klingenberger).