HF US using linear probe and small parts setting demonstrating a sliding lung sign. The highly echogenic pleura can be seen, with the wavy lines of reverberation artefact seen deep to it. The line moves with respiration and cardiac contraction, with the associated small acoustic shadowing artefacts (caused by minor pleural irregularities) that trail downwards moving with it. The internal mammary artery can also be seen pulsating just above the pleura on the right end of the screen.
